Roemheld CLR-4318-211N | 2 Size x 16.8 - 17.7mm Range Bore Clamps without Centering

Roemheld Bore Clamps without Centering-Block Type

Bore Clamps without Centering provide internal clamping and supporting in one unit, exerting force both radially and downward against a hardened support surface. Unlike Self-Centering Bore Clamps, these clamps do not perform a locating function and will not resist excessive side loads during loading or machining, so supplemental locators are required. The block-type version can be easily installed using either standard fittings or manifold mounting with O-ring ports. Bore Clamps are particularly suitable for clamping workpieces with small bored or cast holes and a support surface square to the hole axis. This compact design uses an expanding four-segment Clamping Bushing with teeth that penetrate slightly to exert high downward clamping force. These clamps have a pneumatic connection which can be used for continuous positive air-pressure protection in excessive chip conditions.

Application Information

Block-type Mini Bore Clamps can be easily installed using either standard fittings or manifold mounting with O-ring ports.

Top-flange Mini Bore Clamps provide a low-profile installation using manifold mounting with O-ring ports.

Top-flange cartridge-type Mini Bore Clamps provide an extremely low-profile installation using cartridge-type manifold mounting.

Additional Clamping Bushings, in a Clamping Set with matching Clamping Bolt and Wiper, are available as replacements or to clamp other sizes with the same base unit.

Clamping Action

Mini Bore Clamps are a combination of a double-acting pull-type cylinder and a four-segment bushing which is pulled by a tapered clamping bolt. This causes the bushing to expand radially by spring force to the bore diameter of the workpiece. The simultaneous axial movement forces the workpiece downward onto the hardened support surface of the housing. Downward clamping force is proportional to operating pressure, while radial force is not dependent on operating pressure.

Design Considerations

These clamps do not perform a locating function and will not resist side loads except by the static-frictional force between the workpiece and support surface, so supplemental locators are required (hole-position accuracy must be within +/-0.008"). Clamping force depends on the Clamping Bushing's teeth penetrating slightly and penetration depth will vary depending on the material. Heat treated or hard-coated materials cannot be effectively clamped. The hole to be clamped should not be tapered more than 3°, especially with harder materials (if in doubt, we recommend a clamping test). For best results, air-blast clean the support surface and clamping bushing before every load cycle. In excessive chip conditions, the continous positive air-pressure feature should be used. Clamping Bushings should be replaced after 10,000 clamping cycles.

Mounting & Fluid Supply

Fasten clamp with four socket-head cap screws. A dowel-pin hole is provided on the bottom side of the clamp for accurate location (+/-0.002"). For manifold mounting, the mounting surface must be ground flat to ensure proper O-ring sealing.

Two 1/4" BSPP ports, S for clamping, E for unclamping. For optional manifold mounting, use the S and E manifold ports underneath the clamp by unscrewing the sealing plugs and installing two CLR-3000-342-SW O-rings (Size 1) or CLR-3000-343-SW O-rings (size 2). Also install two CLR-810-F Port Plugs in the 1/4" BSPP ports. These clamps also have two 1/8" BSPP ports for air connection-one marked A for using the pneumatic seat check, and another marked L for continuous positive air-pressure protection against chips. Do not use NPT fittings.

Material

Parts Specification

Warning:

This product can expose you to materials and/or chemicals including arsenic, lead, and other materials and/or chemicals which are known to the state of California to cause cancer and/or reproductive harm.

For more information, visit www.P65Warnings.ca.gov