Industrial gears are cog-like, rotary motion machinery parts used to create or change movement. They can transmit or change the torque (rotational force), rotational speed, and direction of the device or machine to which they are attached.
Compared to gears applied in commercial and consumer products contexts, industrial gears are usually characterized by heavy duty construction and durable metal composition.
Industrial gears are used for two main reasons:
1. They can be used to transfer rotational motion
2.They can be used to produce a change in rotational speed and torque
Gears are used extensively throughout many industries, such as automotive manufacturing, aerospace and aviation, machining, material handling, food processing, textile manufacturing, oil and gas, and automation. Gears are essential to the functioning of equipment and products within these industries and more.
For example, bevel gears, spur gears, and other gear varieties are necessary in all vehicles for the transmission of rotational motion between an engine and a vehicle's moving parts. They are particularly important in auto transmission applications. Also, clocks, bicycles, heavy industrial mining equipment, and oil rigging equipment all depend on gears for the transmission of motion.
Photo Courtesy of Commercial Gear and Sprocket Company, Inc.
Photo Courtesy of Omni Gear Machine Corporation
The History of Industrial Gears
Gears of all kinds descend from gears found in China as early as the 4th Century B.C. The earliest known gears produced in Europe came out of Greece between 150 and 100 B.C.
As far as we know, the first differential gears were used to help run a south-pointing chariot, used by a mechanical engineer named Ma Jun in the second century A.D. Mechanical clocks were first built with gears in China around 725 A.D. Meanwhile, the worm gear was invented on the Indian subcontinent sometime in the 13th or 14th century.
Over the centuries, gears have continued to become more advanced and diverse. Today, industrial gears are incredibly useful and versatile.
The key component of industrial gears are its teeth. These teeth, or cut cogs, work by meshing with teeth from another gear. Usually, the teeth are a part of something called a “gear wheel,” which is simply a toothed wheel.
Most often, manufacturers create gears using net shape molding, a manufacturing technique that focuses on creating parts that are come out as close to the intended final shape as possible. That way, manufacturers won’t have to do as much surface finishing. All of those operations used by manufacturers to produce a semi-finished part are called blanking operations. Processes that fall under this umbrella include: injection molding, powder metallurgy, die casting, investment casting, and sand casting. In addition, manufacturers also make gears using forging methods, as well as, increasingly, 3D printing.
Once the part has undergone blanking, it is known as a gear blank. At this point, the gear blank is typically sent on for further machining. Injection molded and die cast gears do not often require finishing, but gears made by other methods usually do. Powdered metal gears, for example, typically require sintering, while sand castings and investment castings usually require gear cutting. Gear cutting techniques include gear hobbing, gear shaping, broaching, and milling.
To help their products withstand the wear of harsh and repetitive use, manufacturers put their gears through strengthening processes like heat treating and quench pressing.
Gears may be made from a variety of materials, including most metals and hard plastics. Highly wear-resistant plastics such as nylon and polycarbonate are useful in machinery applications where low weight is a requirement. In demanding applications such as automotive transmissions, gears are made from hard metals such as stainless steel, steel, brass, copper, and even titanium.
Two of the main things that manufacturers think about when considering gear design are gear speed and gear performance, which are both determined by gear shape and size. When interlocking gears differ in size from one another, the smaller gear will turn faster than the larger gear; the relationship between gear size and speed is called "speed ratio" or "gear ratio." A gear's number of teeth can be used to calculate a gear assembly's ratio. For example, if two interlocking gears have 40 teeth and 20 teeth respectively, the gear ratio is 2:1.
Another thing manufacturers think about during gear design is diametral pitch, which helps them determine how fast a gear will be able to move within a machine. Diametral pitch is the number of gear teeth per inch of its pitch diameter. You can calculate this by dividing the number of teeth by the pitch diameter. To get the pitch diameter, you need to know the pitch circle, which is the imaginary circle connecting the points at which two interlocking gears meet. The pitch circle divides the gear's tooth into the top of the gear tooth and the bottom of the gear tooth. If the gear system is designed correctly, their pitch circles will be tangent to one another at any point where two gears touch.
Gear applications are variable and highly customizable; any gear can be configured in a virtually limitless number of ways to increase speed, reduce speed, transmit power, transmit motion, or reduce the amount of force necessary to accomplish a task. One of the many ways that manufacturers can customize your gears, for example, is by creating a unique assembly of multiple gears, known as an industrial gearbox. Gearboxes are a great choice for more complex applications. In addition, from 20 foot diameter industrial gears to small worm gears, they can make them as large or as small as you need.
A gear's number of teeth and its specific gear ratio determine the function, speed and control the gear will have within a larger gear assembly. These factors will determine the gear's durability and strength and also the speed it will be able to engage. Specifically, different sized gears are used with one another to increase or reduce a shaft's rotational speed. In addition, interlocking of gears with unequal diameters can produce a change in rotational speed and torque.
Gears work in tandem with one another. When one turns, the other turns with it, because their teeth mesh together. You can begin gear motion in a few different ways. Mainly, you can power a gear with physical force, as you do when you ride or a bike, or mechanical force, as from a machine.
There are many varieties of the industrial gear. First of all, all gears can be divided in the categories of internal gear and external gear. The teeth of an internal gear are on the inner surface of its wheel. (Note: a bevel gear is only considered an internal gear when its pitch angle exceeds 90 degrees.) The teeth an external gear are on the outer surface of its wheel.
Within these two categories are many different gears. Some of those most common types include: spur gears, sprockets, planetary gears, helical gears, differential gears, bevel gears, miter gears, spiral bevel gears, zerol bevel gears, worm gears and pinion gears.
The spur gear is the simplest and one the most common of the industrial gear varieties. Spur gears are also known as "straight-cut gears" and feature straight teeth radiating in alignment with their axes.
Spur gears are often used as sprockets, which are thin gears with teeth that lock easily into roller chains. Sprockets act as a non-slip pulley for power transmission applications; they can be used in combination with bicycle chains, tank treads and other similar chain or tread based movement apparatus. Cylinders or rods with straight teeth called splines are used to transmit motion laterally.
Planetary gears are among the more complicated gear systems. They contain one central spur gear, or "sun gear," surrounded by three or more "planet gears;" the exterior gears interlock with the inward-facing teeth of a larger internal gear, increasing the output speed of the large outer gear through rotational torque applied to the internal sun gear. Planetary gears and other gear configurations like helical gears and differential gears are by nature much more complicated than spur gears. Spur gears can be used in simple and complex applications, but planetary gears are used in drivetrains and other applications where complex gear ratios are required for the smooth transmission of torque.
The teeth of helical gears are inclined toward the axis of the shaft and positioned like a helix, which is how they get their name. These fast rotating gears can endure heavy loads smoothly and efficiently. When it comes to noise comparison, these gears are quieter than spur gears and many other types of gear wheels. In addition, these parts can bear both radial loads and thrust loads. In particular, they’re an ideal utility for automotive motors and transmissions.
The bevel gear is identified by its intersecting shafts, which are located on the same plane. The arrangement of intersecting and coplanar or coexisting shafts is called a bevel gearing system. Users can find many applications for straight and angled bevel gears. However, the thickness and height of the tooth and the shaft should be chosen carefully according the type of application.
Miter gears are a subcategory of bevel gears in which two rotational axes intersect each other at a programmed speed.
Spiral Bevel Gear
This type of gear is designed to meet special purposes using oblique teeth. In comparison to straight gears, the spiral ones can take up more loads.
Zerol Bevel Gear
These are very similar to the straight bevel gears. However, they have teeth that are curved in length, but not angled. Zerol bevel gears can be described as an intermediate type between spiral and straight bevel gears.
A worm gear is a type of helical gear with a fairly long helix angle and body. The worm gear meshes with a worm wheel in order to achieve a high torque, low speed gear ratio.
A pinion gear is a versatile round gear. Usually, it is used as the smaller gear in a gear set, such as a rack and pinion spur gear.
Other types of gears include the cycloidal gear (used in clocks), drive gear (input gear of a gear train), precision gear, hypoid gear, metric gear, plastic gear, parallel shaft gearbox, time gear, ring gear and involute spline gear.
Advantages of Industrial Gears
The biggest advantage of industrial gears is their definite ratio of teeth. This ratio allows industrial gears to move with much more precision than comparable drives, such as the traction drive.
Another advantage of gears is the fact that they have few parts. Fewer parts equal fewer chances for malfunction, less maintenance, easier cleaning, and, ultimately, a longer working life.
There are a fair number of gear accessories out there. These include items like: handwheels, lug drives, miter boxes and stem nuts. Find out what accessories might benefit you by discussing your application with your supplier.
Proper Care for Industrial Gears
No matter how advanced your industrial gears are, to ensure your machines are performing to your expectations and meeting your production demands efficiently, you will need to make sure that your gears are working at optimum capacity. To make sure your industrial gears are in good and working condition, follow the tips detailed below.
Prepare Maintenance Plan
Every technical routine should be exercised as planned. Ask your process engineers to prepare a plan for the care and maintenance of your industrial machinery. While creating the plan, include all the essential and recommended routines of cleaning and maintenance. It should be like a checklist that you work with in your everyday life. In this plan, there should detailed routines of all the tasks that your engineers and maintenance people have to perform.
On-Site Pollution and Dust Management
In addition to this, you should also ensure that there are proper arrangements for dust and pollution management on your site. The absence of a pollution control system may affect your machines and their production quality to a great extent. The layer(s) of dust and pollutants can influence the smooth and controlled rotation of gears, hence, the quality of the production. One way or another, it adds to the overall production cost of the plant. Many process machines, including the production machinery, power generators, and air conditioning systems, generate a heavy amount of pollutants and particulates that reach all over the plant due to a lack of proper pollution management system.
Keep Support Tools Nearby
Your engineers should follow a systematic style of working. That means, when they work, they should have all the tools with them, to avoid any space for mistakes. You need to double check that all the support tools are placed near the machine. For this, you will have to make provisions for tool kits as well as testing and safety devices, near the process machine. Tool belts that you can wear around your waistline while working on the machine maintenance job are an ideal choice. Additionally, you should make sure that the engineers, that have been assigned the task to test out the sufficiency of your machines' industrial gears, have good working knowledge.
Visual inspection before every production cycle - A quick inspection before production begins can help you save big on your fuel charges and ensure quality in your production. Open the gearbox, and have a look at the position of everything that is visible at the first glance. It would be ideal to note down every setting that you see. Alternatively, you can use a HD camera to capture the setting in a quick blink.
Inspect Heat Sources
To make your gears work even better, you can use industrial gear oils. Gear oils lubricate gears, thereby protecting them against heat, vibration, friction and the presence of corrosive elements. Without gear oils, you can expect your gear system to overheat, corrode and generally break down much more quickly. Get the best results by matching the lubrication to your application and gear system based on properties of strength, heat and corrosion resistance.
In general, your manufacturers should follow the standard guidelines set out by ISO (International Standards Organization) and AGMA (American Gear Manufacturers Association).
They should follow other standards per your industry, region and country. These may include Mil-Specs, FDA standards, EPA standards, DIN standards, JIS standards, etc. To make sure your gears are in compliance with every aspect of your application, discuss your specifications in detail with your gear supplier.
Things to Consider
Industrial gears are important hardware, and the decision of what kinds and combinations to get shouldn’t be taken lightly. When setting out to get your gears, remember to consider factors like: intended environment, required speed and movement, required torque, intended frequency of use and your industry.
The best way to get the right gears, though, is to work with the right gear manufacturer. Who is the one is the right one for you? The right one for you is the one that shows you the most consideration and the truest dedication to bringing you a great solution. Don’t know where to start? Don’t worry! Above we have listed many excellent gear manufacturers; start by checking out their websites and reaching out to one or more of them with your questions. We’re sure your manufacturer is among them. Happy hunting!
- are intended to operate on axes that
intersect, usually at a 90 degree angle, to work around corners.
- link two shafts through a covering, forcing the
total of the rotational angles of the shafts to be the same as the
rotational angle of the covering.
- Gear manufacturers are companies that fabricate torque transmission equipment.
have angled teeth to create a thrust load on the gears
when they mesh. Car transmissions often have these.
conduct power and motion between non-intersecting, parallel axes that
may or may not have a center groove, with each tooth making two opposite
are similar to bevel gears but differ by operating on non-intersecting
are round mechanical components that have “teethed” circumferences, allowing them to interconnect with corresponding teethed gear wheels or parts; these gear pairs transfer/reverse motion, increase/decrease rotational speed and torque or synchronized axes.
are defined by the length in millimeters of the pitch
circle diameter per tooth.
bevel gears put together with equal numbers of teeth and axes that are
usually at right angles.
- come in sets of usually two or more that operate on or inside larger industry gears. Planetary gears make drastic gear
are made primarily of plastic, sometimes with both metal and plastic
components. These gears are generally cost effective and light; some
injection molded plastic gears.
- Rear end gears are bevel gears arranged into epicyclic configurations which transmit torque and rotation through three shafts.
- contain a series of ridges on a driveshaft that even out rotation speed of the companion piece.
- are gears with metal teeth that enmesh with chains.
- are cylinder shaped gears that have both straight and
parallel teeth and work on parallel axes.
- have straight teeth that radiate from a center point.
- are similar to helical gears and have a higher potential load transmission
compared to straight bevel gears, which is achieved by cutting the teeth
in a curved shape.
- have a curved and
recessed throat that gives the worm access to the worm gear teeth. Usually
they are made of bronze,
iron or steel.
The distance the width of a tooth space surpasses the thickness of the
engaging tooth on the pitch circles of industry gears.
- The diameter of the hole in an
- The larger gear of a set of
- The smallest distance between the axes of
non-intersecting, mating industry gears.
- Used for connecting two non-continuous shaft
ends of industry gears.
- The distance,
radial or perpendicular, between the bottom of the gullet and the pitch
circle on industry gears.
- The distance between the
teeth of industry gears.
- A cutting tool used for cutting teeth in
industry gears by using a hobbing machine.
- An extension projecting from
the side of industry gears that creates
width to a part so it can be mounted on a shaft.
- The type of style
of the hubs on industry gears. Type 'A' indicates there is no
hub on the industry gear; type 'B' indicates there is a hub on
only one side of the industry gear; type 'C' indicates there is
a hub on both sides of the industry gear.
- The pitch diameter's ratio to the number of
teeth on the industry gear expressed in millimeters.
distance from the crossing point of the axes to the location surface of
- The smaller industry gear of a set of
- The size of the teeth of
- A steel bar with teeth on one side where a pinion can be
driven across. Also a
spur gear with an unlimited pitch diameter.
- The distance from the center
of industry gears to the point where the teeth or edges come into contact
with one other. It is directly related to the size of one industry gear compared
to the other.
- Edges or outside of
industry gears have pits and extrusions to interlock with other industry gear parts.
The teeth of the industry gears prevent slippage between the gears and promote consistency and regularity
in the industry gears.