This article takes an in depth look at gears and their applications.
This article will discuss topics such as:
A gear is a rotating circular device with teeth, crafted to convey torque and adjust speed between shafts, ensuring efficient power transfer.
Also called cogs, gears feature teeth on their cogwheel or gear wheel that interlock to transfer motion efficiently. Operating on the lever principle, these mechanical devices can alter power direction, speed, and torque. As simple machines, gears come in diverse sizes, delivering varying torque levels, thus offering mechanical advantages. The rotational speed and diameter of interlocking gears determine speed. Uniformly shaped teeth are spaced evenly to ensure consistent torque transmission and prevent slipping. Multiple interconnected gears form a transmission or gear train. A linear toothed strip, known as a rack, facilitates linear to rotary translation when gears engage linearly.
Gear classification is based on shape and shaft positioning. Gear shapes can be involute, cycloidal, or trochoidal. Regarding shaft positioning, gears may be parallel shaft, intersecting shaft, or non-parallel/non-intersecting shaft types. Typically mounted or affixed via shafts, the toothed part is fixed to the shaft. When a force is applied, the shaft spins, causing the driven gear to rotate, resulting in rotary motion. Characterized by radius and tooth count, gears exhibit various configurations.
The gear radius differs based on specific gear parts. Essential measurements are the root radius and addendum radius. The root radius spans from the gear's center to the teeth's base, defining the fillet radius where bending stress is highest. Although hard to measure, its accuracy is critical for gear performance. Understanding differences in these measurements is crucial for grasping gear geometry and functionality.
The addendum radius measures a tooth's extension beyond the pitch circle, from the gear's center to the tooth's top. The addendum circle marks the boundary for external gears and internal gears. Often equated to the pitch radius, it's the span from the gear center to the pitch point.
Gear radius dimensions vary with the gear type. Together, the pitch and addendum radius help form the pitch circle's diameter.
Gear teeth are pivotal in engaging with other gears, enabling motion changes. Pitch, or the distance between identical points on successive gear teeth, is vital in gear design. Teeth ensure slippage prevention during power transmission. Historically termed cogs, tooth design and placement are paramount to gear functionality.
Gear teeth are usually cut into a blank but may be individually inserted. When teeth weaken, the entire gear can require replacement. Tooth placement and angle depend on gear type, with teeth available as straight or helical. Positioning can be external, internal, or flattened around the gear.
Though gear tooth structure might seem straightforward, it requires detailed mathematical calculations for accurate design.
Involute gear teeth, predominant for drive and driven gears, are shaped by the base circle diameter. Standard involute teeth can mesh with any gear having identical pitch, pressure, and helix angles. Contact emerges at a single point where spirals intersect.
Key design factors for gear teeth include:
In transferring rotational motion and modifying output speed, gears excel, especially under high loads, thanks to teeth providing precise shaft control.
Addendum - Gears' teeth extend outward in external gears and inward in internal gears from the pitch circle, known as the addendum, spanning between the pitch diameter and outer diameter. The addendum circle is defined by this extension.
Axis - Axes guide gear movement direction and transmission. Parallel axes, where axes remain aligned, are common. Intersecting axes, which are perpendicular, redirect motion direction. There are also non-parallel, non-intersecting axis configurations.
Base Circle - The base circle is a theoretical concept for generating the involute curve crucial for gear tooth profiles.
Circular Pitch - Measured along the pitch circle, circular pitch is the span from a point on one tooth to a comparable point on the next, calculated as an arc. Proper meshing necessitates equal circular pitch across gears.
The module, a gear tooth sizing unit, simplifies calculations involving π (pi), being more manageable than circular pitch as a rational number.
Dedendum - Dedendum is the portion of a tooth below the pitch circle extending to the minor diameter.
Diametral Pitch (DP) - Defined as teeth number to pitch diameter, diametral pitch ensures meshing compatibility. In the US and UK, it's teeth per inch, with higher values indicating smaller teeth.
Fillet - The gear tooth fillet, or trochoid, appears as a cutting byproduct at the tooth's base.
Form Diameter - Form diameter, or TIF, is an imaginary circle connecting fillet curves, smaller than the base circle diameter.
Gear Ratio - Representing gear rotations per single full rotation, gear ratio conveys the speed comparison. Larger drive gears rotate driven gears faster, while smaller drive gears have quicker movement.
Pitch Circle - The pitch circle's dimensions enable tangent alignment for proper gear interfacing, essential for proper gear operation.
Pitch Diameter - The pitch diameter, labeled dm or d2, outlines pitch circle dimensions to gauge necessary gear spacing.
Pressure Angle - Identifying the tangent angle at the pitch circle, the pressure angle is determined by involute shaping tools, usually 14.5°, 20°, or 25°.
Teeth - Gear teeth, projecting outward or inward depending on design, transmit rotation. Internally, they mesh with external gears, common in planetary systems.
Gears are shaped by their tooth profile, often displaying involute curves. Other specialized profiles include cycloidal and trochoidal shapes, all crucial for efficient power transmission.
The profile of a gear tooth spans from the outer to the root circle on cross-sections.
Top Land - This flat surface at a tooth's tip, known as top land, highlights face width, meeting teeth spacing requirements.
Tooth Thickness - Defined by opposing faces along pitch circles, tooth thickness (ts) is calculated rather than measured directly.
Tooth Face - Between the addendum circle and pitch circle, the tooth face describes the protruding surface beyond the pitch surface.
Tooth Flank - Spanning from tip to root, the tooth flank incorporates addendum flank, dedendum flank, and blending surfaces.
Fillet Radius - At the tooth base, the fillet radius, where bending stresses concentrate, presents defining challenges.
Tooth Pitch - Measuring distance between adjacent tooth points, tooth pitch uses measurements such as diametral pitch, circular pitch, and module. Diametral pitch prevails in the US.
Pitch Point - Defining meshing tangency in gear pairs, the pitch point influences gear velocity ratios.
Face Width - The axial tooth extent, or face width, boosts tooth strength. Smaller effective face widths meet compatibility with mating parts.
Mechanical devices with circular forms and edged teeth, gears transmit rotational force and torque across varying machines. Gears pair to prevent slippage by interlocking. Circular gears maintain consistent speed and torque, while non-circular ones permit varied ratios. Shaping gear profiles ensures consistent performance. When the smaller gear, the pinion, serves as the driver, it increases torque while decreasing speed. Conversely, pinions on driven shafts raise speed and lower torque. Properly spaced shaft positioning, whether parallel, non-parallel, intersecting, or non-intersecting, is essential for gear systems. Connected through rotating shafts as levers, gears primarily transfer rotation and energy between parts, leading to three outcomes:
In a setup with 40 and 20 teeth gears, the smaller gear rotates double to keep pace, yielding faster speed but less force.
When a smaller gear has more teeth, speed drops, requiring more force to turn, enhancing force application.
Two gears reverse direction, with one clockwise and the other counterclockwise. Directional changes rely on specialized gears.
Industrial applications use a variety of gears, each designed for specific mechanical functions and performance requirements. The main characteristics that vary among these gears—and are critical to gear design and engineering—include:
Most industrial gears are circular in shape, although specialized applications may require elliptical, triangular, or square gears to achieve unique motion profiles. Circular gears, such as those found in spur and helical designs, provide a constant gear ratio; this means the input rotation speed and torque are consistently transferred between gears—a feature critical in precision machinery and high-efficiency gearboxes. In contrast, non-circular gears offer a variable gear ratio, causing input and output speeds and torques to vary throughout each rotation. These are often used in applications requiring non-uniform motion, such as textile machines, printing presses, and mechanical linkages where acceleration and deceleration must be carefully controlled for process accuracy and automation.
The design, geometry, and configuration of gear teeth are crucial characteristics that directly affect efficiency, load capacity, noise, and service life of a gear train. Each type of gear has a distinct tooth design, which is influenced by factors such as:
The structure of gear teeth depends on the type of gear and its intended industrial application. For example, spur gears feature straight teeth cut parallel to the axis of rotation and are widely used in gearboxes for automotive and manufacturing. Helical gears, on the other hand, feature angled teeth that deliver smoother and quieter performance, making them ideal for high-speed applications in robotics, aerospace, and conveyor systems. Specialized gears like bevel and worm gears require unique tooth geometries to transmit motion efficiently between non-parallel or intersecting shafts.
Gear teeth can be fabricated in two primary ways: cut directly into the gear blank (integral) or inserted separately (segmental or replaceable teeth). Over time, gear teeth may wear out due to friction or overload. When the teeth are integral, the entire gear must be replaced upon wear; however, replaceable teeth allow for modular maintenance, reducing downtime and operational costs—a key consideration in large-scale manufacturing and automation systems where uptime and maintainability are essential.
As for teeth placement, external gear teeth project outward from the gear's center, while internal gear teeth face inward. Proper meshing and orientation are critical in gear design to determine the direction of rotation in a gear train. For instance, two external gears mesh to rotate in opposite directions. For parallel rotation, an idler gear is inserted to reverse the output. Alternatively, a configuration using an external and an internal gear enables both gears to rotate in the same direction, beneficial in planetary gear systems, automatic transmissions, and precision machinery that require compact and efficient motion transfer.
Another key feature affecting gear performance is the tooth profile, which refers to the cross-sectional shape of each tooth and influences contact ratio, speed variation, friction, noise, and wear resistance. The most prevalent tooth profile is the involute, prized for its ability to maintain constant pressure angle and smooth rolling motion, making it the standard in modern gear manufacturing for everything from automotive transmissions to industrial machines. Cycloidal profiles are frequently used in clock mechanisms and precision instruments, while trochoidal profiles are ideal for pump gears and high-precision rotary devices.
Other gear design parameters—such as pitch diameter, addendum and dedendum, module, and pressure angle—are optimized during engineering to maximize load distribution, minimize backlash, and ensure proper lubricant film formation. The gear material, surface hardening techniques, and finishing processes like grinding and lapping contribute to the final quality, lifespan, and application suitability of precision gears for industries including automotive, aerospace, medical, and heavy machinery.
Gears are classified based on the positional relationship of their axes and gear pairs, a foundational concept in gear system engineering and power transmission. The three primary classifications are:
The term "parallel axis gear configuration" refers to power transmission between parallel shafts where the gears mesh to create rolling contact, achieving efficiency levels of 98% to 99.5%. In this setup, the gears are mounted on shafts aligned in the same plane, and the driven gear rotates in the opposite direction to the drive gear, which further enhances efficiency. This configuration provides high transmission of motion and rotation between the connected gears and is prevalent in industrial gearboxes, manufacturing equipment, and conveyor systems.
The types of gears used for the parallel gear configuration are double helical, helical, herringbone element, and spur gears, with spur and helical being the most commonly used. Spur gears are low cost and have a simple design but produce a great deal of noise and may not be ideal for large amounts of torque because of the one-to-one tooth contact, which can lead to increased wear and vibration under heavy loads.
For high torque applications and quieter operation, helical gears are preferred. Their angled teeth increase the ratio of contact, facilitate smoother engagement, and reduce acoustic noise, making them essential in automotive transmissions and industrial machinery. The main disadvantage of helical gears for parallel axis configurations is the axial thrust force produced by the helix angle, which requires specialty bearings or thrust washers to manage these forces.
Gears with a parallel axis configuration offer excellent reliability, ease of maintenance, and a minimal number of components. This setup is the most common gear arrangement and includes pinions and gears, with variations suited for speed increasers, speed reducers, and multi-stage gearboxes. Parallel gears are often categorized into configurations such as double increaser, reduction, triple increaser, or reduction gear.
The intersecting gear configuration features two axes that cross at a single point within the same plane. A crucial aspect of this configuration is ensuring precise gear alignment, with mounting distance being a critical engineering parameter. Proper positioning involves aligning the locating surface on the back of one gear with the plane of the action apex. For optimal meshing and contact, the gear base cone apex, the mating pinion base cone apex, and the plane of apex must all meet at the same spatial point, ensuring maximum efficiency and reduced gear wear.
Intersecting gears are often housed in robust gear enclosures that support the gear shafts and integrate bores for shaft support. Maintaining proper shaft alignment during gear operation is crucial to prevent vibration, minimize backlash, and extend equipment lifespan, especially in high-speed applications such as automotive differentials, right-angle reducers, and heavy-duty drilling machinery.
The shafts for intersecting gears are positioned at an angle, usually 90 degrees, allowing for adjustments in torque and speed based on application requirements. This configuration can help save installation space, improve lubrication to the tooth surfaces, and reduce the bending stress on gear teeth.
Bevel gears, including straight, spiral, and miter types, are typically used for right-angle gear drives. While they may have higher costs and lower torque transmission compared to parallel shaft gear arrangements, their conical structure and angled teeth allow for effective change of rotational axis and smooth power transition. Bevel gears are essential in automotive axles, marine drives, and industrial mixer drives, where compact size and right-angle power transfer are paramount.
In some machinery, gears are required to transmit power between shafts that are neither parallel nor intersecting, leading to the use of non-parallel/non-intersecting gear types. Unlike common gear pairs that depend on direct tooth-to-tooth engagement, these configurations transfer rotational power primarily through relative slippage between the surfaces. The rotating shafts are typically arranged at right angles but do not share a point of intersection, resulting in lower efficiency and torque transmission. Typical examples include worm gear drives, hypoid gears, and crossed helical gears, which are used where silent operation, high-speed reduction, or compact layouts are required.
Non-parallel and non-intersecting configurations often utilize spiral or skew bevel gears to facilitate smooth engagement and load sharing, even when shafts are set at odd angles. For applications requiring significant speed reduction, the worm gear system is highly effective. This features a threaded worm (similar to a screw) in mesh with a spur gear. The worm gear creates high speed reduction ratios in a single stage, and its self-locking properties are advantageous in lifting equipment, conveyor systems, and automotive steering mechanisms.
The hypoid gear configuration resembles bevel gear arrangements but features offset axes, providing smooth operation, higher torque capacity, and quieter running. Hypoid gears are commonly found in automotive axles and heavy-duty industrial machinery, where strength and efficiency are critical. Crossed helical gears are used in machine tools, printing equipment, and complex automation systems requiring motion transfer between non-parallel axes.
When selecting gears for a specific application, critical design factors must be evaluated. These include the material composition of the gears (such as steel, bronze, nylon, or composites), surface hardening treatments (case hardening, carburizing, nitriding), the module or diametral pitch (which determines tooth size and spacing), the number and angle of teeth for torque transmission, and the type of industrial lubricant required for optimal wear resistance and thermal stability. Proper consideration of these metrics, in addition to dynamic loading, noise tolerance, and operational environment, ensures maximum performance, safety, and efficiency in all types of gear-driven systems.
For engineers, designers, and equipment buyers, understanding the nuances of gear design and selection empowers informed decisions that reduce maintenance costs, extend equipment lifespan, and optimize overall mechanical efficiency. Consult with leading gear manufacturers for custom solutions and state-of-the-art gear engineering tailored to your unique industrial requirements.
Choosing the right gear material is a critical stage in gear manufacturing, directly impacting gear strength, longevity, and overall system performance. Engineers and gear designers must balance mechanical properties like tensile strength and hardness with factors such as wear resistance, weight, corrosion resistance, manufacturability, and price point. The application—be it heavy-duty industrial machinery, automotive transmissions, or high-precision instruments—drives the selection process, ensuring the material meets operational demands while optimizing cost-efficiency over the gear’s lifecycle.
Gears are fabricated from a variety of materials to address wide-ranging engineering challenges. Common gear materials include alloy steel, carbon steel, tool steel, stainless steel, brass, bronze, cast iron, ductile iron, aluminum alloys, powdered metals, and engineering-grade plastics. Among these, steel—particularly alloy and carbon steels—is the most prevalent due to its exceptional strength-to-weight ratio, machinability, heat treatment versatility, fatigue resistance, and competitive cost. However, non-ferrous metals and specialty polymers are increasingly chosen for niche applications that demand corrosion resistance, lighter weight, quieter operation, or unique mechanical properties.
Steel remains the material of choice for most gear applications in sectors such as automotive, aerospace, power transmission, and industrial machinery. Its broad range of grades and heat-treatability make it ideal for producing strong, precise, and long-lasting gears tailored to different operating conditions.
Cold rolled steel is an iron-based alloy, often comprised of low to medium carbon content, that undergoes a secondary rolling process at room temperature to refine its grain structure and surface finish. This enhances yield strength, dimensional accuracy, and fatigue resistance, making it especially suitable for gears that require tight tolerances and smooth running surfaces. The process results in a steel roughly 20% stronger than hot rolled alternatives, delivering higher tensile and yield strengths crucial for high-load gear applications such as transmission gears, timing gears, and industrial power gears.
Cold rolled steel is typically supplied in sheets or plates of varied thicknesses to accommodate methodologies like hobbing, gear shaping, and broaching. Its improved surface finish enables quieter, more efficient gear engagement, while its stability ensures manufactured gears retain precise geometry throughout thermal cycling and operational stresses. This makes cold rolled steel a preferred material for high-precision gears demanding dimensional stability and wear resistance.
Conversely, hot rolled steel, though strong and inexpensive, is unsuitable for gearmaking. Its mill scale surface texture and lack of precision preclude manufacturing components with the tight tolerances and fine surface finishes required in professional gear applications.
Tool steel alloys are engineered to deliver outstanding wear resistance, hot and cold hardness, and toughness under demanding conditions. Typically containing high carbon, chromium, vanadium, tungsten, and molybdenum, tool steels such as MTEK A2, D2, and H13 are renowned for their edge retention and abrasion resistance—properties that make them highly suitable for specialty gear manufacturing in environments with high torque, impact, or extreme temperatures. Tool steels are available in seven main categories, including water-hardening, cold-work, hot-work, and shock-resistant types; cold-worked tool steels are especially favored for gear production due to their machinability and microstructural stability.
High carbon content and carbides improve the hardness and load-bearing capacities of tool steels, while alloy additions increase heat resistance and durability. They are ideal for applications like precision cutting gears, press-fit assemblies, and aerospace gears subject to repeated shock loads. Manufacturing gears from tool steel involves processes like blanking, forming, hobbing, and stamping, leveraging the alloy’s favorable response to both mechanical and heat treatments for enhanced gear performance.
Iron-based alloys, particularly carbon steel, play a key role in both high-volume and specialty gear manufacturing. Carbon steel is selected for its combination of affordability, hardness adjustability, and readily available forms. This class of material is organized by carbon content—mild (<0.3%), medium (0.3�0.6%), and high (>0.6%)—with each type offering distinct attributes for different gear profiles including spur gears, helical gears, racks, bevel, and worm gears.
Induction and laser hardening processes can significantly increase the wear resistance and load capabilities of carbon steel gears. Alloy steels, incorporating elements like chromium, nickel, and molybdenum, further boost toughness and surface hardenability, plus offer better corrosion resistance—key for marine gears, mining applications, and exposed mechanical drives. Engineers often specify alloyed iron for heavy-duty power transmission gears and high-cycling industrial gear sets due to its robust physical properties and adaptability to surface treatments.
Stainless steel, an iron alloy with at least 11% chromium content, is increasingly utilized for gears requiring exceptional corrosion resistance, longevity, and hygiene—attributes essential for food processing, chemical handling, and medical device industries. Main classes include ferritic (400-series), austenitic (300-series), martensitic, and precipitation-hardened types. For gearmaking, stainless steel 303 is prized for its machinability due to sulfur addition, while 304 is the general purpose workhorse for corrosion-resistant parts.
Where superior chemical and saltwater corrosion resistance is necessary, 316 stainless steel is chosen—commonly used in marine gears, pharmaceutical mixing gears, and outdoor equipment. Stainless steel gears, though more expensive than standard carbon steels, justify the cost in scenarios where gear life, minimal maintenance, and optimal cleanliness are priorities. Gear types produced from stainless steel include precision spur gears, helical gears, and bevel configurations.
Copper alloys are strategically utilized in gear manufacturing for their excellent corrosion resistance, non-magnetic properties, and ease of machining. Common copper alloys for gears include brass, phosphor bronze, and aluminum bronze. These copper-based materials excel in low-noise, low-load applications or where lubrication access is limited, thanks to their inherent lubricity.
Brass, a blend of copper and zinc, can be tuned for ductility, while phosphor bronze—comprising copper, tin, and phosphorus—adds stiffness and high wear resistance, ideal for high-duty worm gears and heavy sliding contacts. Aluminum bronze is noteworthy for its strength, oxidation resistance, and durability in harsh conditions, making it suitable for heavy-load marine and industrial gears exposed to brine or acids. The ability of bronze gears to self-lubricate improves gear life and performance, especially in worm gear drives or instruments where friction reduction and maintenance are key user requirements. As a result, copper alloy gears are commonly selected in marine, food service, and instrumentation industries for specialty motion control applications.
Aluminum alloy gears stand out for applications that demand a balance of strength, light weight, and corrosion resistance—such as robotics, aircraft, lightweight automotive systems, and portable devices. Weighing about a third as much as steel, aluminum alloys help reduce inertia, improve system responsiveness, and simplify assembly in weight-sensitive projects.
Common alloys include 2024 (aluminum-copper), prized for its strength, 6061 (aluminum-magnesium-silicon) for excellent weldability and corrosion resistance, and 7075 (aluminum-zinc-magnesium) for its maximum strength-to-weight ratio under dynamic loads. All can be heat treated and surface finished (e.g., anodizing) to further enhance wear resistance and durability. Aluminum gears are frequently specified for moderate-load, moderate-temperature jobs (operating below 204°C/400°F), encompassing spur gears, helical gears, straight bevel gears, and racks connected to lightweight structures or high-cycle motion assemblies.
Plastic gear manufacturing has dramatically expanded in recent years, especially for electronics, appliance drives, and medical device actuation systems where quiet operation, corrosion resistance, and cost control are crucial. Top gear plastics include polyacetal (POM), nylon (polyamide), polycarbonate, polyphenylene sulfide, and polyurethane—each offering different properties regarding dimensional stability, moisture absorption, impact strength, and thermal performance.
Engineering plastics can be blended or filled with additives such as glass fiber, carbon fiber, or lubricants to tailor stiffness, temperature limits, friction coefficients, and wear characteristics. Combining polymers lets manufacturers produce precision-molded gears with optimized noise reduction, low inertia, and high efficiency, desirable for high-speed and compact gear trains. The lightweight nature of plastics (roughly 15�20% the mass of equivalent steel gears) also lessens power requirements and increases energy efficiency across rotating assemblies.
Some advantages of plastic gears include inherent design flexibility, lower material and production costs, substantial noise attenuation for quiet running, high efficiency, and good durability in light to moderate load conditions. Thermoplastic polyesters are often preferred over nylon for applications needing long-term dimensional accuracy, as nylon gears may absorb water and swell. The low friction coefficient of most plastics ensures minimal wear and reduced energy consumption, contributing to the popularity of polymer gears in consumer electronics, printers, and automotive actuators.
Understanding the various types of gears is crucial for selecting the right one to ensure effective force transmission in mechanical designs. Key factors in gear selection include its dimensions, such as module, number of teeth, angle, and face width.
A gearbox, or gear drive, is engineered to enhance torque from a drive motor, decrease the motor's speed, and alter the rotational direction of shafts. It connects to equipment or motors through couplings, belts, chains, or shafts. At the core of a gearbox are its gears, which work in pairs, engaging with one another to transmit power.
Gears play a crucial role in the effective operation of processes, equipment, machines, and complex mechanisms. They efficiently transfer motion, force, power, and torque between various components. Gears are categorized by type, class, and their specific functions, each designed to optimize performance. A clear understanding of the different gear types and their parameters is essential for effective planning and operation of equipment and systems.
Bevel gears are conical in shape and the teeth of this gear are placed around its conical surface. These gears are used in applications where there is a need for change around its axis of rotation. These gears transmit energy and power to the intersecting shafts by changing its rotation. The configuration angles that are required for bevel gears is usually 90 degrees though not always. Bevel gears are made with cast steel, plain carbon steel, and alloy steels. All have different characteristics and can be used according to their applications.
Crown bevel gears, also known as face gears and contrate gears, have helical teeth in the form of a spiral with a pitch angle that is equal to 90°. They mesh with other bevel gears, spur gears, and a pinion system to change rotary motion at a right angle. The projection of the teeth at a right angle to the plane of the wheel gives them the appearance of being a crown. Unlike conical bevel gears, crown bevel gears are cylindrical to be paired with other gears according to tooth design.
Crown gears are frequently used in applications where low noise is essential. They interact with a rack's interlocking cog, enabling the gear to move smoothly along the rack. While crown gears fell out of favor early in the 20th century, they have seen a resurgence due to the industry's shift towards energy-efficient and technologically advanced drives. The optimal integration of crown gears with motors, gearboxes, and control systems is leading to notable energy savings.
Crown gears are increasingly used due to the decentralization of drive technology, which is essential for the flexibility of modern industrial operations and the growing number of drives. The demand for efficient transmissions has led to a greater need for crown gearboxes to meet these requirements.
Hypoid bevel gears transmit rotational power between shafts positioned at right angles, making them ideal for heavy-duty truck drive trains. In a hypoid gear set, the smaller pinion gear shaft is offset from the larger crown gear shaft, so the gears do not intersect. This offset allows the pinion to have a larger diameter and a greater spiral angle, enhancing the contact area and tooth strength..
The spiral angle of hypoid bevel gears facilitates smooth meshing between the pinion and crown gears. This design increases tooth strength and contact area, allowing for a wider range of gear ratios and the transmission of higher torque. The benefits include reduced wear, lower friction, minimized energy loss, and enhanced efficiency.
Hypoid gear sets can distribute loads across multiple teeth simultaneously, with an average contact ratio of 2.2:1 to 2.9:1. This extended tooth-to-tooth contact allows hypoid gears to transmit higher torque compared to similarly sized bevel gears.
The advantages of hypoid gears have made them increasingly popular for speed reduction in power transmission and motion control systems. To accommodate this trend, manufacturers are designing motor flanges with hypoid gearboxes, enabling various motors to be mounted directly onto the gearbox housing.
Bevel gears are widely used across industries such as cement, beverage, food, mining, energy, and bulk handling. They are commonly employed in medium to large conveyors, crushing equipment, water treatment systems, and mixers.
Miter gears are employed for right-angle drives with a 1:1 gear ratio between intersecting shafts, particularly in applications requiring high efficiency. For proper meshing, miter gears must have the same number of teeth, pitch, and pressure angle. They can be used in sets of more than two gears. The axial thrust generated by miter gears necessitates the use of ball bearings or sleeve bearings to absorb this force and prevent separation. Miter gears are mounted at right angles, and hardened miter gears offer 50% more horsepower capacity and greater wear resistance compared to non-hardened miter gears.
Miter bevel gears are widely used for their ability to handle high speeds and torque loads smoothly and quietly. However, their use is limited to changing the direction of transmission because they cannot alter the transmission speed, as they have the same number of teeth. When miter bevel gears have spiral teeth, they are paired with right and left-handed configurations.
Spiral bevel gears have a curved angle of teeth placement. It is more angled and also provides gradual teeth to teeth contact than that of straight bevel gears. This gradual engagement of teeth greatly reduces the vibration and the noise that is produced even at high velocities. Spiral bevel gears are also available in left and right hand angled teeth. Spiral bevel gears are difficult to manufacture and have a structure. However they have greater tooth strength, smooth operations, and low noise during operations.
Straight bevel gears are the most commonly used gears in many industries, because the tooth design is so simple and can be manufactured easily. The teeth of straight bevel gears are designed so that when a perfectly matched straight bevel gear comes in contact, it fits with each other at once and not gradually. This adjustment of teeth produces lots of noise while working and also increases the stress that is produced on the gear’s teeth. All these reduce the lifespan and durability of the gear and machine.
Zerol gears are the combination of both spiral and straight gears. These gears have all the characteristics of both kinds of gears. Zerol gears have curved teeth that are placed straight on the conical surface. This means that zerol gears are used in the same applications as that of straight gears, however, zerol gears are much quieter and have less friction compared to straight gears. Additionally zerol gears are not placed at any angle therefore, these can rotate in any direction and are also available in both left hand and right hand design.
Internal gears are the ones which have teeth that are placed on the inside of the diameter of the cylinder. Internal gears are the best to use for high transmission of energy in small areas, low noise production, less vibration, low speed reduction, and low cost. Internal gears are also called ring gears and are ideally used for areas where there are space issues. The mating of external gears results in rotation in opposite direction and if there is mating of external and internal mesh then the rotation will be in the same direction.
The material used for manufacturing internal gears depends on its application. Usually, forged steel, cast and ground steel, aluminum, and plastic material are used.
A helical gear is a type of gear that has parallel configuration. This type of gear is also used for non parallel and non intersecting configuration. The teeth of helical gears are twisted around the cylindrical body and angled towards the gear face. Helical gears are designed with left and right hand angled teeth. Each gear pair is composed of a right and left hand gear of the same helix angle. This angled tooth design gives helical gear an advantage because it can mate with other gears differently than those of straight cut teeth. If the mated pair is perfectly matched to each other then the contact level between the corresponding teeth is at a maximum and at intervals, rather than the whole tooth engagement at once. This engagement will help in reducing the noise created from machines and also lower the impact on the teeth.
Some disadvantages of helical gears are that it may work with great efficiency but its capacity is quite less than that of spur gears. Along with that the tooth design of these gears is quite difficult to manufacture and also costs a lot. Single helical gears also create axial thrusts thus; there is a need for thrust bearing in the applications that use single helical gears. This necessity also increases the cost related issues of these gears. Helical gears are made of aluminum, bronze, steel, and nylon. Other subtypes of helical gears are:
Left handed and right handed helical gears that have the same twist angle are referred to as double helical gears, which transmit rotational motion between two parallel shafts. They have the same advantages as other helical gear, including strength and low resonance, with the added advantage of being able to cancel thrust forces with their combination of right and left hand twists. The unfortunate aspect of double helical gears is the extra amount of effort that is necessary to manufacture them.
Double helical gears and herringbone gears are the same type of gear but with slight difference between the gears, which is a groove that is in the center of double helical gears while the groove is absent from herringbone gears. The configuration of double helical gears with two helical gears at the same angle with opposing thrust forces enables them to annihilate each other's thrust forces to overcome axial thrust.
Herringbone gears are double helical gears that have adjoining gear teeth. As with double helical gears, the teeth on herringbone gears are right and left hand gear teeth that have the appearance of the letter V and are designed to cancel out their mutual thrust. Like most helical gears, herringbone gears operate quietly, smoothly, and at high speeds. One of their main characteristics, like most helical gears, is the engagement of multiple teeth during each rotation, which distributes the load and is the reason for their quiet operation.
The teeth of herringbone gears can be manufactured such that tooth tips align with opposite tooth tips or with the opposite gears tooth trough. They are manufactured in pairs and are more expensive than other helical gears due to their complex tooth profile. In some cases, two opposite hand helical gears that are adjacent with a milled center, flat groove. As with most gears, herringbone gears are mounted on a hub or shaft with a hub being cylindrical and placed on one or both sides of the gear.
Shaft mountings of herringbone gears include keyway, set screw, split, or simple bore. Of the four mounting types, keyway mountings can only be used with shafts that have a cutout while set screw, split, and simple bore mountings do not require a special type of shaft.
Screw gears are also a sub type of helical gears and they are used for non parallel and non intersecting configurations. Herringbone gears are employed as right hand and left hand pairs but screw gears are employed for the same hand pair. These types of gears are usually low capacity and low efficiency and cannot be used for high power applications.
Helical gears are widely used in industries like cement, beverage, food, mining, marine, energy, forest, and bulk material handling. Its applications are for medium to large conveyors, mixers, large pumps, water treatments, and crushers. Double helical gears and herringbone gears are used in mining, marine, and heavy industries. It is also used in milling, steam turbines, and ship propulsions.
Single helical gears have a single row of teeth that are cut at an angle to the axis of the gear along a spiral path in a single left hand or right hand helix. They are able to develop axial thrust and radial thrust with low power transmission. The common helix angle for single helical gears is between 15o and 45o since high helix angles cannot be used. Single helical gears mate slowly, which results in reduced vibrations, noise, and teeth wear. Like spur gears, single helical gears are used to transmit motion and power between parallel shafts. Unlike spur gears, single helical gears have to be used in pairs due to the angle of their teeth.
The versatility of single helical gears makes it possible to mount them parallel to each other or on shafts at right angles to each other, an arrangement that is similar to worm gear and shaft configurations. The gradual engagement and quick release of single helical gears eliminates the shock and jar that is found in spur gear teeth operating under heavy loads. Shaft support bearings for single helical gears have to be strong because of the end load that is produced by their use.
Different types of plastic gears are now widely used in the engineering industry for manufacturing gears. Plastic gears are becoming the first choice of many industries due to their wide range of applications and its availability to work in all types of configuration. Plastic gears are used in a parallel axis configuration such as helical cylindrical gears, double helical gears, and spur cylindrical gears. It is also available for non parallel configuration such as bevel gears, screw gears, and worm gears. Plastic is also used in gears that are used for special applications such as internal gears and rack and pinion gears.
A variety of plastic gears can be made according to the application and can be differentiated on the basis of shape and shaft position. Plastic material is melted and can be molded into any required shape. The material could be PVC, Teflon, or nylon.
Plastic gears are the best option in industries because these are noise dampening, less vibratory, manage the impact load, low cost, low weight, reduced coefficient of friction, absorbs shocks, low maintenance and protects the teeth from wear and tear by distributing the load. Along with all these advantages there are some disadvantages of using plastic gears. These gears have low capacity of load carrying, can be negatively affected by certain chemicals, high cost of initial molds and greater dimensional instability.
Plastic gears are widely used in cameras, toys, electronic equipment, wall clocks, projectors, speedometers and many other home appliances that use plastic gears in their working.
Rack and pinion is a gear pair and it consists of a gear rack and a gear that is cylindrical in shape known as pinion. The gear rack is a flat bar that has infinite radius and it also has straight teeth that are inserted on the surface of the bar. The configuration of these gears is dependent on the type of pinion gear with which these are mated. If it is mated with a spur gear then it is parallel and if it is mated with a helical gear then it is angled. Both these designs can be used in a rack. The rotational movement can be changed into linear one and linear can be changed into rotational one. One rack and pinion gear advantage is the design of this gear. It is also the simplest to manufacture and is also low in cost. But there are some limitations to this design in that the transmission of energy cannot continue in one direction for infinite time. The motion can be limited by the length of the rack, and a great space present between the mated pair which will create a lot of friction and stress on the teeth of the gear.
The material that is used in rack and pinion gears are aluminum and steel. This gives maximum strength to these gears.
Rack and pinion gears are commonly used in the automotive industry in steering systems and also in weighing scales.
Spur gears are the most common type of gear. They have a circular or cylindrical body with teeth that are cut straight and are aligned parallel to the gear shafts. Mated pairs of spur gears are placed in a parallel axis configuration for transmission of motion and power. The mating of spur gears depends on their application, since they can be mated with other spur gears, internal gears, or a planetary gear.
Spur gears are widely used because their tooth design is simple, allow for a high degree of precision, and are easy to manufacture. The drawbacks to spur gears is their inability to handle axial loads, high speed, and large loads. As with many forms of gears, spur gears create a great deal of noise when operating in high speed applications. Regardless of these complications, spur gears have a very high efficiency rating.
Spur gears are made from brass, steel, and plastics and are divided into external gears and internal gears.
The distinctive feature of external spur gears is the placement of their teeth on the external circumference of the gear with the teeth jutting out and away from the center of the gear. The teeth of an external gear are cut on the outside surface of the cylinder, pointing away from the center. During motion and transmission of power, the input and output shafts move smoothly in opposite directions as the external gear teeth mesh.
When external gears mesh, they have a narrow contact surface due to the convex pairing of the flanks of the teeth, which leads to high tooth loads, referred to as Hertzian contact stress, causing extensive wear on the gears and flanks of their teeth . When an external gear is pair with an internal gear, a convex or concave flank pairing occurs, which results in a larger contact area and lower tooth loads and reduced wear. The pairing results in higher torque transmission than would be possible between two external paired gears.
External gears are the most popular type of gear and considered to be the simplest gear system having straight teeth that are parallel to their axis. In all instances, external gears are used to transmit rotary motion between parallel shafts and have a small gear, or pinion, that drives a larger gear. The contact between the gears is noisy, which increases at high speeds. Since external gears are frictionless, they provide a smooth ride.
Unlike external gears, internal gear teeth point inward, toward the center of the cylinder. The teeth have the same shape as that of other spur gears with the differentiating factors being their location and their direction. The appearance of an internal gear is that of a smooth circle with teeth cut into the inner portion of the circumference of the circle. This view of internal gears has led to them being named ring gears due to their resemblance to a special form of ring.
The design of internal gears places the centers of their mating gears closer together than is possible with external gears, which makes them ideal for applications where space is a problem. Their increased area contact makes it possible for internal gears to produce stronger drive due to the increased area contact with less sliding. One of the most popular uses for internal gears is as part of planetary gear systems, also known as epicyclic gears, to serve as the support for the sun and its planets.
One of the benefits of internal gears is the protection they offer against the intrusion of dirt, dust, and other obstructions. The limited use of internal gears is due to their complexity and the high cost of manufacturing them.
The spur gears are widely used in many industries such as food, forest, unit handling, beverage, automotive, and energy. It has a variety of applications such as uses in clocks, washing machines, watering systems, small conveyors, package handling equipment, automotives, planetary gear sets, and many more.
Worm gears are also called cylindrical gears or screw shaped gears. It consists of a worm wheel and a worm or screw shaped gear. These gears are manufactured to work with non parallel and non intersecting configurations. The design and angle of these gears is such that the worm can make the wheels rotate but the wheels cannot change the rotation of the screw or worm. This mechanism works in machines that require self locking ability. These gears have a high gear ratio and capacity making them suitable for work in a quieter environment and producing less noise. Some disadvantages include low transmission power and a lot of friction that is produced during functioning. This friction requires lots of lubrication for these gears to run smoothly.
The material that is used for manufacturing worm gears is steel for the worm or the screw that is placed in between and bronze or cast iron for the gears. This combination gives a high speed of rotation to these gears.
Worm gears are used in food, beverage, automotive, forest, energy, and unit handling industries for small conveyors, package handling equipment, lifts, elevators, and farm machinery.
Differential gears are made up of two halves of an axle with a gear placed on the ends of each half, which are connected by a third gear to form three sides of a square. In some instances, a fourth gear is added to complete the square. To complete the set, a ring gear is added to the differential casing that holds the three or four core gears in place, which is connected to the drive shaft by a pinion to power the wheels.
This arrangement of gears is the most common form of differential gear set, is referred to as an open differential gear set, and is used to develop more complicated differential gear sets. It enables the axle of a vehicle to corner smoothly and is less expensive to produce than more complicated differential gears.
Although open differential gears are commonly used, they are the foundation for all forms of differential gears including locked, welded and spool, limited slip, torsen (torque sensing), active, and torque vectoring. Each of the different types of differentials are designed to control torque, slippage, and other factors related to differential gear performance.
The term industrial gears covers a wide range of gears that transfer power between systems, allow for a variety of speeds and loads, and achieve a fixed range of input speeds and loads. The list of industrial gears includes all of the gears described above each of which is included in a system, process, or special configuration.
The standards for industrial gears have been established by industries, applications, and regions of the country. Standards for gears in the United States are in compliance with the American Gear Manufacturing Association (AGMA), which assists in setting up the global standards of the International Standards Organization (ISO).
Industrial gearboxes enhance the output torque and alter motor speeds with a shaft of a motor linked to the gearbox. The gear ratio of the gearbox determines the output torque and speed depending on the arrangement of the gears. The designs of gearboxes vary according to the industry for which they are manufactured with the different industrial uses being agricultural, construction, mining, and equipment for automotive production. The various configurations of gearboxes are available individually or in combination depending on the application.
The most commonly used types of industrial gearboxes are helical, coaxial helical inline, bevel helical, skew bevel helical, worm reduction, and planetary, each of which is used to improve a company’s efficiency and industrial capacity. They are an essential component to the production of products and assisting in the maintenance of industrial systems.
There are several factors that distinguish nylon gears from traditional metal gears with their lubricity and noise reduction being two of their most outstanding qualities. Nylon is a strong engineering plastic with exceptional wear qualities and properties. It is often used for the manufacture of bearings and bushings due to its lubricity.
For certain applications, nylon is stronger than steel and lasts longer. There is a long list of different types of nylon, each of which has been engineered to meet the needs of different applications. As part of the research regarding the use of nylon, different polyamides have been developed, some with one monomer and others with two monomers with each having different properties. When two types of nylon are polymerized together, they form a copolymer that is identified with a dash between the numbers. The distinctions for nylons continues with new combinations being constantly developed.
Of the long list of nylons, the nylon that is used to manufacture gears is PA610 or nylon 610, which is tough, rigid, and heat resistant with low moisture absorption and resistance to UV, chemicals, wear, and zinc chloride solutions. Since it can be used for injection molding and extrusion, it is the ideal nylon for the manufacture of high precision gears used in a variety of climatic conditions.
Planetary gears, also known as epicyclic gears, are a multi-gear set that includes an internal gear, a central gear or sun, a planetary carrier, and one or more other gears known as planets. All of the gears in the set are spur gears, including the internal gear. The multiple gears in a planetary gear make it easy to adjust, change, and convert gear ratios. The engineering of the components provides stability due to the even distribution of mass and rotational stiffness.
The types of planetary gears are categorized by their performance, efficiency, and versatility with all types being able to change two inputs into a single output. They provide exceptional torque with proportional stiffness and little noise. The types of planetary gears include single stage, multi-stage, inline, offset, right angle, harmonic, simpson, Ravigneaux, and differential. These nine types are a small sampling of the many types of planetary gears and does not include ones that have been specially designed for unique applications.
There are an endless number of functions that planetary gears perform, which include speed reduction, increase torque, and sharing a load with multiple gears due to the even distribution of a load that makes planetary gears resistant to damage. Planetary gears are used in rugged applications because of the load distribution and their robust design that is able to handle high torque and reductions.
Rear end gears provide mechanical leverage that multiplies torque to help engines move machines. As the gear ratio gets higher, rear end gears provide more leverage to help with acceleration. The gear ratio of a rear end gear refers to the gear ratio between the driven gear or ring and the drive gear or pinion, which is calculated by dividing the number of teeth of the ring gear by the number of drive gear teeth.
The purpose of rear end gears is to ensure that a vehicle can handle different rotational speeds when turning corners and being reversed. Their structure includes bevel gears, spur gears, and planetary gears. A typical rear end gear set includes bevel gears, an axle, shafts, and a carrier with teeth that come in several varieties and are arranged into an epicyclic configuration that makes it possible to attach axles that turn at different speeds. These components are used to multiply the torque from the engine and transmission and assist in the operation of a machine or the movement of a vehicle.
The ratio of rear end gears can be explained with an understanding that higher ratios of rear end gears provide better acceleration or torque while lower gear ratios offer fuel economy and better top speeds. Rear end gears have exceptionally high performance when transmitting motion and force and offer high reliability and longevity.
Small gears turn very quickly with less force and are used to increase the force of other, larger gears. They rotate at a faster speed and require less force. The principle of gear transmission ratio is when two gears of different diameters mesh and rotate together, the gear with the larger diameter will rotate slower than the smaller gear. How the gears are arranged, small to large or large to small, determines the amount of speed that will be generated by their connecting.
To increase speed, a larger gear receives power from the motor. As it turns once, the speed of the smaller gear greatly increases because one turn of the larger gear makes the smaller gear turn multiple times and faster. In many cases, one turn of a larger gear can cause a smaller gear to turn four times faster.
If a small gear is providing the power to turn a larger gear, movement will be slower since multiple turns of the smaller gear produces one turn of the larger gear. This motion produces higher torque and force making it possible to slowly move large loans.
The relationship between large and small gears is mainly seen in spur gears with different diameters. Several small gears can be found in planetary gears and are used for the same principle of changing torque, power, and speed. In the case of planetary gears, the sun gear or central gear is normally larger than the planet gears and receives the power that is to be changed and transmitted.
Spline gears are rods, such as drive shafts, that have teeth to transfer torque between machine parts by meshing with the teeth on a mating piece internal spline shaft. They are like gears in that they have teeth along their exterior that lock in place with the teeth of their mated internal spline shaft. Spline gears are unlike gears in that they use all their teeth to transfer torque while gears transfer torque one tooth at a time. They mesh with an equal number of teeth with their mating piece.
The manufacture of spline gears takes several different forms and includes broaching, shaping, milling, hobbing, rolling, grinding, and extruding. The most common forms of spline gears are parallel key spline gears, involute splines that are related to involute gears, and serrations. Internal spline gears are made the same way as external spline shafts with the only exception being the use of hobbing due to accessibility problems.
Splined gears or shafts transfer torque using an externally splined shaft mated with an internal shaft with slots for the external shaft’s teeth. The driven shaft can be the internal or external one. Spline gears have their teeth built into the full length of the shaft, which makes them more efficient at preventing rotation and transmitting torque.
Sprockets are wheels with teeth or notches around their circumference that are able to engage chains or belts that have the same thickness and pitch. They have the appearance of gears but are not designed to mesh with one another. Sprockets are commonly seen on bicycles and motorcycles as the chain drive. They are made from steel and aluminum with steel being the more durable and long lasting.
The parts of sprockets include the number of their teeth, their pitch and outside diameters, and the pitch per tooth. Much like the diameter of gears, the pitch diameter is the diameter of a sprocket that is the circumference of the sprocket beneath its teeth while the outside diameter is the circumference at the end tips of the teeth. The pitch is the measurement of each tooth that needs to fit into the pins on a chain and is precision calculated.
Double duty sprockets have two teeth per pitch to advance a second set of teeth when one set wears out. Hunting tooth sprockets have an uneven number of teeth that change every time the sprocket rotates to save on tooth wear. Segmental rim sprockets make it possible to remove the rim of the sprocket without the need to disturb the chain. When higher torque is required, multiple strand sprockets are used that are capable of handling higher power such as being powered by a drive shaft.
Sprockets that are fitted to a shaft are pilot bore and taper bush. The common use for pilot bore sprockets is on industrial machinery. They have a cylindrical projection that is drilled to the size of the bore and are fixed to a shaft using grub screws, pins, or locking bushings. Taper bush sprockets have a split through the taper and flange for clamping on a shaft.
Gears are an industry essential that are used for the transmission of motion and power in clocks, instruments, machinery, vehicles, and industrial equipment. They are engineered to reduce or increase speed in motorized implements and change the direction of power smoothly and efficiently. Since their introduction thousands of years ago, gears have become an essential tool for the innovations and improvements of industry.
Made from highly durable materials, gears play a key role in the productivity of machines and the operations of manufacturing. Each type of gear has varied elements, characteristics, advantages, and properties that meet the requirements and specifications for motion or power transmission. The wide variety and number of gears makes it possible to find a gear for every application.
One of the main functions of gears is to change the rotation speed of power with engines being the most common example. Gears regulate power by their ratios with different sizes of gears used to increase or decrease transmitted power by their rotation.
During the transmission of power, gears intermesh with other gears without slipping and strongly retain their connections. The motor in a machine may not be designed to move a shaft directly and uses gears to transmit power to the shaft to power a tool.
Torque is the rotating force that is produced by motors and engines that is adjusted through the use of gears, gear sets, gearboxes, and gear assemblies. Smaller gears produce less torque while large gears produce higher amounts of torque. When a small gear is the drive gear to power a large gear, the amount of torque increases and speed decreases. Taken in reverse, when a large gear is the drive gear and a small gear is the powered gear, the amount of torque decreases and speed increases.
A common use for gears is the changing the direction of rotation or movement, which is completed by the specific design of gear pairs. The rotational direction of a motor is dependent on the rotation of a shaft with the direction of the rotation capable of being changed by the configuration of the gears.
Gearboxes are one of the most common uses of gears and are made up of an assortment of gear types contained in a housing. Gearboxes contain worm, bevel, helical, and spur gears that are engineered to change torque, speed, power, motion, and force. Gearboxes are a foundational part of motor driven vehicles and gas powered machinery.
A bevel gear is a toothed rotating machine element used to transfer mechanical energy or shaft power between shafts that are intersecting, either perpendicular or at an angle. This results in a change in the axis of rotation of the shaft power...
A gear is a particular kind of simple machine that controls the strength or direction of a force. A gear train is made up of multiple gears that are combined and connected by their teeth. These gear trains allow energy to move from...
A planetary gear is an epicyclic gear that consists of a central gear, referred to as the sun gear and serves as the input gear, which has three or more gears that rotate around it that are referred to as planets...
A plastic gear is a toothed wheel made up of engineering plastic materials that work with others to alter the relation between the speed of an engine and the speed of the driven parts. The engineering plastic materials used in manufacturing plastic gears can be...
A spur gear is a cylindrical toothed gear with teeth that are parallel to the shaft and is used to transfer mechanical motion and control speed, power, and torque between shafts. They are the most popular types of cylindrical gears and...
A worm gear is a staggered shaft gear that creates motion between shafts using threads that are cut into a cylindrical bar to provide speed reduction. The combination of a worm wheel and worm are the components of a worm gear...
Ball screws are mechanical linear actuators that consist of a screw shaft and a nut that contain a ball that rolls between their matching helical grooves. The primary function of ball screws is to convert rotational motion to linear motion. Ball nuts are used in...
A lead screw is a kind of mechanical linear actuator that converts rotational motion into linear motion. Its operation relies on the sliding of the screw shaft and the nut threads with no ball bearings between them. The screw shaft and the nut are directly moving against each other on...
Powder metallurgy is a manufacturing process that produces precision and highly accurate parts by pressing powdered metals and alloys into a rigid die under extreme pressure. With the development and implementation of technological advances...
Thread rolling is a type of threading process which involves deforming a metal stock by rolling it through dies. This process forms external threads along the surface of the metal stock...