PTFE Flanged Bushings for Manual-Valve Operating Levers

Manual valve operating lever bushings support an external pivot or lever shaft where the actuator design calls for a plain bearing. A copper-plated SF-1-F sleeve can be reviewed where a compact radial guide and flange fit the mounting space. The operating lever pivot is distinct from a wetted valve-stem guide or pressure seal.

Copper-coloured flanged composite bushings with split cylindrical sleeves — Existing BONIU product image reused as a construction example. It is not a photograph of this application or proof of an alloy grade. The approved drawing defines the supplied part.

Support the external lever pivot without treating it as a valve seal

Hand force or an assisted linkage creates torque and bearing reactions through the lever arm. Infrequent operation may include long dwell, exposure to weather or contamination and a high starting force. The flange should locate the lever without unintended clamping friction. Identify whether the bearing is fully outside the process-fluid boundary.

Start with the matching BONIU product construction. Send the assembly section as well as the individual bearing drawing so that the working contact, locating surfaces and installation access can be reviewed together.

Dimensions and operating data for quotation

Review item	Required information
Lever arrangement	Pivot diameter, sleeve length, lever arm, support spacing, hand/actuator force and travel.
Flange stack	Flange diameter/thickness, spacers, shaft shoulder and specified axial clearance.
Construction and exposure	Backing/lining specification, copper-plated finish, outdoor or chemical exposure and actual pivot temperature.
Purchase specification	Drawing revision, quantity, units, exact material or composite specification, finish, inspection-document requirements and delivery destination.

Selection boundaries and installation

Install squarely with support that protects the flange and lining. Verify free lever travel after the fasteners are tightened to the assembly specification. Keep the fluid seal and bearing functions separate. Exterior copper plating does not establish suitability for process chemicals or a corrosive atmosphere.

Material and replacement approval

For SF-1/DU-type composites, identify the backing, PTFE-based running layer and exterior finish separately. DU-type describes a product family here, not an original branded bearing or a guaranteed equivalent. Product colour and a reused image cannot confirm material. Required documentation, dimensions and manufacturing scope are reviewed with the quotation.

Agree the material, counterface, operating clearance and acceptance criteria before approving a replacement. Include any required dimensional inspection, material documentation or sample review with the RFQ so it can be addressed in the quotation.

Purchasing questions

Can this bushing seal the valve stem?

No sealing performance is claimed. Specify pressure and fluid sealing elements separately.

Can operating torque be used directly as radial bearing load?

Provide the lever geometry and force directions so the joint reactions can be reviewed.

Does the copper finish prove a solid-copper sleeve?

No. It is an exterior treatment on a composite construction; the backing and running layer are separately specified.

Can the original product image be used to approve this application?

No. It illustrates the bearing structure. Use the approved part and assembly drawings to confirm dimensions, material, clearance and duty.

Request an application-specific quotation

Send your drawing and the checklist above through the BONIU enquiry page. Identify any proposed substitution explicitly so it can be reviewed before order confirmation.