Clamps

How to Choose a Hydraulic Tube or Hose Clamp

A clamp is sized to the line it carries and to the working pressure of the circuit. Confirm these before ordering:

• Line outside diameter: measure the tube or hose OD, not the bore. Clamp bodies are cut to a specific OD or grouped by tube series, and an oversized half-shell will let the line walk under vibration.
• Clamp series and group size: most stackable clamps follow a standard group sizing where one rail mounts multiple lines; match the series so weld plates and cover plates interchange.
• Body material: polypropylene or polyamide for general routing, aluminum or steel for high-temperature, high-vibration, or heavy-line runs. Verify material against your fluid temperature and ambient conditions.
• Working pressure of the line: the clamp should match or exceed the rated pressure class of the tube or hose it restrains, since surge and pressure spikes drive the reaction load into the clamp.
• Mount and reaction hardware: confirm weld plate, cover plate, and bolt thread so the clamp anchors solidly and the reaction load transfers to the frame, not the fitting.

Which Clamp Is Right for the Job?

Single clamps hold one line and suit short, isolated runs; stackable clamps share a rail and twin bolts to bundle several lines along a common path, which keeps a manifold or pump feed tidy and serviceable. Polymer-body clamps damp vibration and resist corrosion on most routing; metal-body clamps take higher temperatures and heavier lines near a pump or motor. If a clamp on the machine is unmarked, confirm fit by measuring the line OD with calipers and counting the lines per rail, then match the series and group size before you order.

Complete the System

Clamps are the last step in a clean routing job, so build the run around the components they secure. Pair them with Hydraulic Hoses sized to the same OD, and anchor the lines feeding your Hydraulic Pumps and Hydraulic Motors where vibration is highest. Lines running to Hydraulic Cylinders benefit from clamping near direction changes to control whip, and Pneumatic Quick Couplers on auxiliary lines stay aligned when the run upstream is clamped square.

Cross-Referencing an Obsolete Clamp

Many machines run clamp series that the original maker has discontinued or rebranded, and a missing half-shell can idle a line that is otherwise sound. A hydraulics distributor since 1963, Northern Hydraulics can match a clamp by tube OD, series, group size, and mount style rather than by a part number that may no longer exist. Measure the line, note how many lines share the rail, and request a cross-reference.