How to select a clutch to connect or disconnect a power train.
Nexen has three distinct types of clutches in several sizes to connect and disconnect the prime-mover [usually an electric motor] to and from the driven load. Clutches allow the motor to run continuously in to save energy and extend motor life.
Multi-position tooth clutches produce high torque in a small package and provide more torque than friction clutches for non-slipping, slow-speed applications. Single-position tooth clutches provides accurate input-to-output indexing. Both versions are available in standard open face versions or nickel-plated, enclosed versions for wash-down environments.
Multiple Disc friction clutches are a good choice for high-torque in a small package and engage in random positions. This type of clutch is recommended for slow-speed non-cyclic applications.
Single and dual plate friction clutches are designed for continuous starting of loads and are typically selected based on transmitted horsepower and speed. These clutches tolerate some slippage at the interface. The load inertia, cycle rate and clutch thermal horsepower capacity are application considerations.
To calculate torque requirements use the following formula:
Torque = 63,025 X HP X Reduction Between Motor And Clutch X Service Factor / RPM
The service factor is subjective and takes into account application severity, engagement frequency, safety, and life. 1.5 is the recommended minimum.
Example
A clutch is required to disconnect the power of a 10 horsepower, 1750 RPM motor from the drive shaft of a printing
press. Exact registry of the printing rolls is required when the clutch is engaged. The clutch is mounted on the 7/8" driven shaft and is connected with a chain and sprockets at a speed ratio of 1:1. This application is classified as an occasional start. Select a clutch based on the transmitted horsepower and RPM. Use a service factor of 2.
Torque Calculation: Torque = 63,000(HP)(Reduction)K/RPM
= 63,000(10)(0)2/1750 = 720 inlbs.
The registration requirement and sprocket mounting make a 5H##P-SP single positioning tooth clutch the best choice. Compare the calculated torque and required bore size to the models listed on the 5H##P-SP comparison page.
Unit Selected: A 5H30P-SP, Single Position Tooth
Clutch Product Number 912100.
Controls:
3-Way Normally Closed Control Valve Engages Clutch When Power Is Applied.
Related Products:
Tooth Clutches
Multi-Disc Clutches
Torque Limiters
Download:
Disconnect Function Example
For more information contact:
Technical Support
(800) 843-7445
info@nexengroup.com
|
