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The Working of Hydraulic Clutches

When the output torque of a system needs to be paused for any reason, a mechanical device known as a clutch is used. Relying on the use of friction to engage the input and output ends of an assembly, a clutch is able to detach a driveshaft from its input shaft. Clutches are often comparable to brake systems in terms of some design elements, both using disc and drum designs. In this blog, we will provide a brief overview of the hydraulic clutch in particular, allowing you to better understand its use and importance within various applications.

As stated before, hydraulic clutches may come in disc and drum variations. A disc hydraulic clutch in particular is often compared to the manual transmission of an automobile, featuring a dual-sided friction material that is pressed between the pressure plate and flywheel. If a higher amount of torque is needed and/or smoother engagement, a hydraulic disc clutch assembly may utilize more friction plates.

Unlike disc clutches, drum clutches feature radially located direction pads that are situated within a drum. With the use of hydraulic or spring pressure, the friction pads may be pressed to the drum so that torque may be transmitted as needed. As drum clutches exhibit an optimal amount of rotational inertia, they do not require a flywheel for operations. However, some assemblies may require a lighter clutch assembly if there is a need for rapid acceleration of the drivetrain. In these instances, a plate type clutch with a flywheel of low mass may be the best option.

In order to have a clutch engage or disengage, there are various options that one may take advantage of. Generally, the most popular options are hydraulics, pneumatics, or levers. Generally, the choice between each will be based on the particular needs of a system, such as hydraulic clutch components being best for applications that require a high drive capacity, high horsepower, or high torque. As a result, the hydraulic clutch is one of the highest performing options with its capabilities.

In order for a hydraulic clutch to function as intended, it utilizes donut-shaped actuators known as annular cylinders to direct hydraulic pressure against a piston. By forcing the piston against the thrust plate of the assembly, clutch engagement is maintained as needed. While a dry clutch utilizes pre-lubricated bearings and actuates the clutch with hydraulic fluid, wet clutches utilize fluids for lubrication, cooling, and pressure.

While the cylinder element of a clutch is often a rotating assembly, this is not always the case. Typically, a clutch that rotates requires a rotary union that is hard plumbed to the clutch. Additionally, these clutches will often need to be mounted end to end with the hydraulic pilot serving as the element for actuation. As this permits disconnection at the drive and driven sides, parasitic energy loss is avoided.

If you are in the market for various hydraulic clutch components or hydraulic system parts that you can steadily rely on, there is no better alternative to ASAP Domain. ASAP Domain is a premier purchasing platform belonging to the ASAP Semiconductor family of websites, and we are your sourcing solution for all the various parts and components you require to carry out your operations with ease. As you explore our expansive list of offerings, take advantage of our provided RFQ services to request quotes for your comparisons. Within 15 minutes of receiving a completed RFQ form, a dedicated account representative will reach out to you with a customized solution based on your needs. Get started today and see how ASAP Domain is forever changing the part procurement process for the benefit of our customers.


November 18, 2022


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