Coupling
Why Choose Us
Established in 2002, Lishui Yongrun precision machinery company is located in Lishui, Zhejiang Province, China, covering an area of more than 28,000 square meters. The company has more than 200 employees, including more than 50 senior technical staff. We specialize in producing Motor Shaft Coupling, Gw Coupling Rigid Shaft, GS Aluminum Alloy Single Diaphragm ClampingGic Aluminum Alloy Rigid Shaft Coupling, Flexible Double Disc Coupling, Aluminum Flexible Shaft Coupling, and other Coupling.
Wide Product Range
Our production of linear rail, ball screw, linear module, linear optical axis, linear bearings, roller needle bearings, rod end joint bearings and a series of high-precision, high-tech linear transmission products.
Wide Range of Applications
Our products are widely used in automated machinery and equipment, such as machine tools, printing machinery, chemical machinery, medical machinery, woodworking machinery and robots, etc.
Products Sell Well
We have established long-time cooperation relationships with customers from all over the world, including Asia, Europe, Africa, North America, South America and many other regions and countries, and have won customers' agreed recognition and praise!
Quality Assurance
Our many product have been granted national patents and have reached a number of international testing and certification standards.
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Motor Shaft Coupling
The characteristics of the coupling diaphragm are a bit like a bellows coupling, in reality the way
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Gw Coupling Rigid Shaft
The clamping shaft coupling of diaphragm coupling makes use of the tightening force of bolts to cut
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GS Aluminum Alloy Single Diaphragm Clamping
The elastic diaphragm coupling relies on the metal diaphragm to transmit the torque and take in the
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Gic Aluminum Alloy Rigid Shaft Coupling
Flexible couplings are usually cut from a metal wire rod made of commonly used substances are
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Flexible Double Disc Coupling
Flexible couplings are used to link 2 rotating shafts that are now not aligned in order to transmit
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Aluminum Flexible Shaft Coupling
Due to different structures and materials, the couplings used in the transmission systems of
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Aluminum Alloy Bellows Clamping Coupling
Most of the commonly used couplings have been standardized. Under regular circumstances, it is
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Aluminium Flexible Beam Coupling
These couplers are made of machined aluminum and have a spiral cut that makes them slightly
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Stepper Motor Coupler
Due to different structures and materials, the couplings used in the transmission systems of
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Servo Motor Coupling
The diaphragm coupling can compensate for the axial, radial and angular deviations between the
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Servo Coupling
Couplings belong to the category of general mechanical components and are used to connect two
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Flexible Winding Shaft Coupling
Most of the commonly used couplings have been standardized. Under regular circumstances, it is
What is Coupling
Linear shaft supports, also called shaft support blocks, are components that position the shafts on which linear bushings or bearings slide. Typically two shafts are arranged parallel to each other and supported by four shaft supports. If you want to know the specifications and prices of Coupling, please contact us!
Advantages of Coupling
Power Transmission
Power transmission between two shafts is the primary function of shaft couplings. Power is transferred from the driveshaft to the driven shaft through a shaft coupling connected between them. The driveshaft is rotated by a power source (maybe electrical or mechanical). The shaft coupling then facilitates the rotation of the driven shaft.
Shaft couplings eliminate the need for a long, one-piece shaft. The use of a one-piece shaft is expensive and it is difficult to transport, assemble, and maintain, and it can cause inaccuracies. If a one-piece shaft fails, its entirety must be replaced. This makes the use of two-coupled shafts a more practical move.
Shaft couplings make power transmission between two shafts that differ in diameter possible. They are also used if the shafts of two different pieces of equipment are manufactured separately.
Accommodation of Misalignment and Shaft Positioning Errors
Aligning and positioning the drive and driven shafts with high precision is difficult and takes a considerable amount of time. Even though both shafts have the same specifications, there are still machining errors that can affect the alignment and shaft positioning accuracy.
The presence of shaft misalignments has negative effects on the power transmission system. It is caused by thermal expansion or deterioration of alignment and positioning caused by vibrations, movement, or bumps during motion. It significantly reduces the efficiency caused by power losses. Unwanted forces are exerted on the surrounding parts as the shafts rotate; this causes vibration and noise. It also increases wear and the risk of mechanical failure due to the induced stress of the misalignment. Therefore, a shaft coupling must be used to absorb such mounting and positioning errors and misalignments.
Shaft misalignments occur in different forms and usually exist in combinations. Parallel or radial misalignment exists when the centerlines of the shafts are parallel but are offset from each other by 0.5 degrees on one end and -0.5 degrees on the other end with a spacing tube between them. In an angular misalignment, the centerlines of the shafts are not parallel; they intersect at an angle. Both forms may occur horizontally or vertically. Lastly, in an axial misalignment, the adjacent ends of the two shafts are displaced away from each other in the axial direction.
Protection to the Overall System
Shaft couplings protect the nearby components in several instances. They dampen vibration, which affects the accuracy of other components (e.g., ball screws, actuators). They reduce the effect of shock loads (or torque changes) from one shaft to another. Flexible couplings can provide electrical isolation when sensitive electronic components are being driven in a high voltage environment.
If an external impact acts on the system, the shaft coupling will prevent transmission of the impact to the equipment. This is important as the impact can damage the equipment.
Shaft couplings prevent the transfer of heat originating from the power source to the driven shaft. Thermal expansion causes the surrounding components to shift from their correct position, causing degradation of their accuracy.
Thermal Expansion Coefficient
The Thermal Expansion Coefficient (CTE) drives the change in the length of a driveline. As operational temperatures change a motion, they must be prevented by the axial compliance at the couplings. Lack of perfect installation, temperature change of one of the machines, or suspension travel contribute to the parallel offset. Heat causes thermal expansion of different components, which makes having a coupling capable of axial compliance critical.
Larger misalignments can be handled by Hooke joints and gear couplings but are not at constant velocity and involve galling, wear, lubrication, and more mass. Constant velocity joints, such as diaphragm couplings, can accommodate less rotation at each end but allow for prescribed bending stiffnesses with improved boundary conditions that allow for higher speeds before resonance.
If a design, using constant velocity diaphragm couplings, is pushed to two degrees of rotation or more at each end, then a high transmitted torque will have a trigonometric component of this torque converted to bending of the flexible elements, which is an unstable and usually fatal situation. Reducing the bending rotation at each end requires a longer spacing tube for the same parallel offset and a lower first bending frequency, which is a design challenge.
Types of Coupling
Rigid Coupling
As the name suggests, a rigid coupling permits little to no relative movement between the shafts. Engineers prefer rigid couplings when precise alignment is necessary.
Any shaft coupling that can restrict any undesired shaft movement is known as a rigid coupling, and thus, it is an umbrella term that includes different specific couplings. Some examples of this type of shaft coupling are sleeve, compression and flange coupling.
Once a rigid coupling is used to connect two equipment shafts, they act as a single shaft. Rigid couplings find use in vertical applications, such as vertical pumps.
They are also used to transmit torque in high-torque applications such as large turbines. They cannot employ flexible couplings, and hence, more and more turbines now use rigid couplings between turbine cylinders. This arrangement ensures that the turbine shaft acts as a continuous rotor.
Flexible Coupling
Any shaft coupling that can permit some degree of relative motion between the constituent shafts and provide vibration isolation is known as a flexible coupling. If shafts were aligned all the time perfectly and the machines did not move or vibrate during operation, there would be no need for a flexible coupling.
Unfortunately, this is not how machines operate in reality, and designers have to deal with all the above issues in machine design. For example, CNC machining lathes have high accuracy and speed requirements in order to perform high-speed processing operations. Flexible couplings can improve performance and accuracy by reducing the vibration and compensating for misalignment.
These couplings can reduce the amount of wear and tear on the machines by the flaws and dynamics that are a part of almost every system. As an added bonus they're generally rather easy to install and have a long working life.
Sleeve or Muff Coupling
Sleeve coupling is the simplest example of a rigid style coupling. It consists of a cast-iron sleeve (hollow cylinder) or muff. It has an internal diameter equal to the external diameter of the shafts being connected. A gib head key is used to restrict the relative motion and prevent slippage between the shafts and the sleeves.
Some sleeve couplings and shafts have threaded holes that match up on assembly to prevent any axial movement of the shafts. The power transmission from one shaft to the other occurs through the sleeve, the keyway and the key. This shaft coupling is used for light to medium-duty torques.
The sleeve coupling has few moving parts, making it a sturdy choice as long as all the parts are designed keeping in mind the expected torque values.
Split Muff Coupling
For easier assembly, the sleeve in a sleeve coupling can be divided into two parts. By doing this, the technician no longer needs to move the connected shafts for assembly or disassembly of a coupling.
This is what a split muff coupling or a compression coupling is. The two halves of the sleeve are held in place using studs or bolts.
Similar to sleeve coupling, these couplings transmit power through the key. Split muff couplings are used in heavy-duty applications.
Flange Coupling
In flange couplings, a flange is slipped onto each of the shafts to be connected. The flanges are secured to each other through studs or bolts and onto the shaft by a key. Using set screws or a tapered key ensures that the flange hub will not slip backwards and expose the shaft interfaces.
One of the flanges has a protruding ring on its face, while the other has an equivalent recess to accommodate it. This type of construction helps the flanges (and, in turn, shafts) maintain alignment without creating any undue stress on the shafts.
Gear Coupling
A gear coupling is very similar to a flange coupling. However, it is a flexible type of coupling and can be used for non-collinear shafts. Gear couplings accommodate angular misalignment of about 2 degrees and parallel misalignment of 0.25…0.5 mm.
The setup for gear couplings consists of two hubs (with external gear teeth), two flange sleeves (with internal gear teeth), seals (O-rings and a gasket) and the furnished fasteners.
The power transmission between the two ends of the coupling occurs through the internal and external gears in the gear coupling.
Gear couplings are capable of high torque transmission. As a result, they find use in heavy-duty applications. They require periodic lubrication (grease) for optimum performance.
Oldham Coupling
Oldham coupling is a special shaft coupling used exclusively for lateral shaft misalignment. When two shafts are parallel but not collinear, an Oldham coupling is most suitable.
The design consists of two flanges that slip onto the shaft and a middle part known as the centre disc. The centre disc has a lug on each face. The two lugs are actually rectangular projections that are perpendicular to each other and fit into the grooves cut out into the flanges on each side.
The flanges are fixed to the shaft through keys. Thus, the power transmission takes place from the driving shaft to the key to the flange to the centre disc and then through the second flange to the driven shaft.
Oldham coupling is ideal for scenarios where there is a parallel offset between two shafts. Such parallel misalignment can happen in cases where power transmission is needed between shafts at different elevations. When the shafts are in motion, the centre disc goes back and forth and adjusts for the lateral variation.
Diaphragm Coupling
Diaphragm couplings are great all-rounder shaft couplings. They can accommodate parallel misalignment as well as high angular and axial misalignment. They also have high torque capabilities and can transmit torque at high speeds without the need for lubrication.
Diaphragm couplings are available in various styles and sizes. The structure consists of two diaphragms with an intermediate member between them. The diaphragm is basically one or more flexible plates or metallic membranes that connect the drive flanges on the shafts to the intermediate member through bolts on both sides.
Diaphragm couplings were initially developed for helicopter drive shafts. But over the years, they have found much use in other rotating equipment as well. They are most commonly used in turbomachinery due to their high-speed function. Applications today include turbines, compressors, generators, aircraft, etc.
Jaw Coupling
Jaw coupling is a material flexing coupling. It finds use in general low power transmission and motion control applications. It can accommodate any angular misalignment. Similar to diaphragm couplings, jaw couplings do not need lubrication.
This coupling consists of two hubs with intermeshing jaws that fit into an elastomeric spider. The spider is usually made of copper alloys, polyurethane, Hyrtel or NBR and is responsible for torque transmission.
Due to the elastic nature of the spider, it is suitable for the transmission of shock loads. It can also dampen reactionary forces and vibration pretty well.
Engineers use jaw couplings in applications such as compressors, blowers, mixers and pumps.
Beam Coupling
A beam coupling is a machined coupling that offers high flexibility in terms of parallel, axial and angular misalignment. It is one of the best low-power transmission couplings.
A beam-style coupling has a cylindrical structure with helical cuts. The attributes of these cuts, such as their lead and the number of starts, can be modified to provide misalignment capabilities of varying degrees. In fact, engineers can make these changes without sacrificing the structure's integrity as it is made of a single piece. Thus, a second name for beam coupling is helical coupling.
In essence, beam couplings are actually curved flexible beams. They are available in single-beam and multi-beam versions. Multi-beam couplings can handle greater parallel misalignment than single-beam couplings.
Tips for Using Couplings in Your Application
Don't Choose Your Coupling Based on Habit or Price Alone
Because engineers are creatures of habit, choosing a coupling type is often a matter of having selected that same type for a previous project. However, because not all couplings are created equal, specifying out of familiarity often mismatches equipment needs with coupling capabilities. Another source of error is choosing a coupling based on price rather than performance requirements. Driven to reduce machinery costs, engineers may shortchange the application by being overly thrifty in their coupling choice. While this approach may reduce upfront component costs, extensive and expensive backend warranty claims can wreak havoc on an OEM's bottom line and product reputation.
● Another error is picking the wrong size: Choosing a coupling that is too large or too small for an application causes problems every time. An engineer must know the forces and loads to which a coupling will be exposed. Simply guessing at load requirements based on motor torque or belt capacities, for example, and then upsizing or downsizing the coupling, causes either design overkill or serious under-design. Either way, the overall machine is inefficiently designed, ultimately costing both OEM and user more to operate.
Determine the Best Way to Mount Coupling to Shaft
The method by which a coupling is mounted on the shaft may determine the success or failure of that coupling, regardless of whether it is the right for the job. Traditional keys, keyways, and taper bushings work well in unidirectional applications with minimal shock or reversing loads. For reversing loads and shock applications, keyless locking devices are the preferred mounting method because keyless devices are backlash-free. For example, mounting a torsionally rigid, backlash-free, high-speed disc coupling with a keyway and setscrew negates the backlash-free nature of that coupling. A keyless locking device would serve the coupling's intended purpose better. On the other hand, mounting a highly flexible jaw coupling with a keyless locking device could be overkill based on the rough and flexible nature of that coupling style.
Ask Yourself What the Coupling Should do
Perhaps most important is to ask oneself, "What should this coupling do?" Further questions: Does it need to transmit high or low torque? Is the application high or low speed? Does it need to be maintenance free? How about backlash free? Are there misalignments between components to be compensated, and by how much? Does the application require the coupling to absorb shock? How crucial is cost? What about weight? How about environmental conditions, such as ambient temperature, moisture, and corrosives? Knowing the answers to these questions with regard to the application and cross-referencing against available couplings will result in selecting the most ideal coupling for the application. Remember: More than one coupling type may work.
Be Aware of Correct Terminology
Inch-pounds or inch-ounces? It may seem obvious, but the units of the coupling's torque rating are commonly confused. Getting the spec wrong can cause you to miss the proper coupling choice by more than an order of magnitude. Another area of confusion involves the use of keyways: Keyway couplings are for high torque, not high precision. If the application requires reversing torques or direction plus precise positioning between the driving and driven shafts, keyways are inappropriate. Instead, a coupling with setscrew or clamp-style hubs is the best solution for precision applications. One more note - if you need zero-backlash, get zero-backlash. Many types of couplings, including flexible bellows shaft couplings, allow no backlash, while others styles permit some backlash to occur.
Watch for Under or Overrating
● Underrated couplings: Using a coupling with a torque rating insufficient for the application can damage or break the coupling, compromising the desired transmission. Overrated couplings: If a flexible shaft coupling is chosen with a torque rating higher than required, it may be unnecessarily bulky and stiff. Typically, the higher the torque rating of the coupling, the larger and less flexible it is.
Another issue is surprise deflections. Flexible shaft couplings are designed to transmit torque, while providing compliance in some combination of compression/extension, bending, and offset. Unanticipated deflections can shorten coupling life. In short: Understand (or at least conservatively estimate) the operating deflection modes when choosing a coupling.
Inertia
The inertial mass of the rotating system has a significant impact on the demands put on your coupling. Both the rate of acceleration and rate of deceleration needs to be factored in. Sudden braking of a high-speed or high-inertia system can cause a large torque spike to pass through the coupling resulting in its damage.
Axial Motion
While a machine is running it may be heating up and cooling down or operating at an elevated temperature. When this happens, there can actually be some relative movement between the shafts that had not been considered previously. The reason this is important is that not all coupling solutions are capable of axial compliance, and are considered axially rigid. The risk in this situation is the possibility of putting a large axial load onto the bearings of the motor. The same motor loading can be true with thrust loads.
In a motion control system, there can be loading of the motor bearing if a solid coupling is used and transmits axial loads to the motor before engaging thrust bearings.
Parallel Offset
Parallel offset is a more difficult misalignment to accommodate than angular misalignment. Couplings generally do a good job at .010 inches and below (parallel offset). Once you start hitting .020 inches or more of offset, you're going to have a harder time finding a coupling that's going to fit in a relatively compact package. If you find a coupling that has a large parallel offset capability be sure and check its speed rating. Usually when a coupling can handle a large parallel offset the product is limited in its maximum RPM rating.
Environment
Keep in mind if the coupling is operating in a harsh environment and/or corrosive atmosphere. Different materials will need to be considered depending on the type of environment. In a severely corrosive environment, specialty materials such as MP35N or Titanium may be the best option. Another environmental consideration is temperature. Certain alloys lose significant strength at elevated temperatures, or for certain elastomeric type couplings, the temperature limits may be limited. In higher temperature applications Inconel may be the material of choice. If the coupling is used in food or medical environments then the material options might be limited to certain stainless steel or Titanium.
RPM
Many applications are relatively easy to solve with most couplings if you're operating at 5,000-10,000 RPM. In today's high-speed applications it may be possible to reach 25,000 RPM, and sometimes up into 75,000-80,000 RPM. You'll need to factor in not just torque capacity but how well balanced is the coupling for that type of speed because if it's not either a balanced coupling or design that's symmetrical by nature, which makes it a statically balanced part, you're going to be running into a vibration situation due to the imbalance.
Performance Rating
When looking for your best coupling solution, remember there is no governing body for couplings and how their performance is rated. It could be from calculations or the results of testing by the manufacturer. Make sure that you read the data carefully because one manufacturer may have a torque rating and when you look at the footnotes, their torque rating is for static torque which means it's the torque that will yield the coupling versus another company that uses a dynamic torque, where the rating based upon a high-cycle environment. We actually de-rate the coupling torque capacity based upon realizing that they're going to be going through millions and millions of revolutions.
Frequently Asked Questions
Q: What is coupling and its type?
Q: What is the purpose of coupling?
Q: What is coupling and an example?
Q: What is coupling vs cohesion?
Q: What are the two main types of coupling?
Q: What are coupling fittings?
Q: What is coupling in software?
Q: Is coupling good or bad?
Q: How to reduce coupling?
Q: Is tight coupling good or bad?
Q: What is a real life example of cohesion and coupling?
Q: What is the difference between dependency and coupling?
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