SHAFT COLLARS • LOCKING DEVICES
Some Ruland collars function as mechanical stops
Clamp-style shaft collars for medical equipment
Clamp-style shaft collars work as guides, spacers, and stops on medical equipment, but only collars with tightly controlled face-to-bore perpendicularity (with a TIR of less than or equal to 0.05 mm) satisfy the design requirements in these critical designs—especially where the collar functions as a load-bearing face or aligns critical motion components such as bearings or gears. Clamp-style shaft collars distribute compressive forces evenly around the shaft for strong hold. Two-piece collars have more holding
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power than one-piece designs and install in place. In fact, machine integrators can add these collars to a design at any point in the manufacturing process. Some shaft collars use fastening hardware that tests beyond industry standards for maximum torque capabilities and holding power. For example, some stainless-steel shaft collars sport hardware that can also resist
corrosion and satisfy regulatory standards; the stainless hardware undergoes surface treatment to prevent galling. Other clamp-style shaft collars come in steel with a black oxide or zinc finish, aluminum, titanium, and engineered plastic. Black-oxide on steel resists corrosion and smoothens screw installation to boost the transfer of screw clamping forces to the collarshaft interface while preventing stick-slip.
In this image we see a hygienic clamping assembly from Ruland on a mozzarella production machine. The collar is located on the outside of the machine and holds the shaft in place in the event of failure. This component is made of a 303 stainless steel shaft collar and other FDA compliant materials. It has none of the surface irregularities, like saw cuts and screw pockets that allow bacterial contamination in other types of shaft collars. This uniform surface allows for easy clean-up around the moving parts of the machine. The collar is also IP69K rated for dust and water up to 176°F/80°C with 10 MPa of pressure.
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