QSn4-4-4 Flanged Bushings for Textile Edge-Guide Pivots

Enquire about QSn4-4-4 flanged bronze bushings for the steering-frame pivots of a textile web edge-guide assembly. The intended purchase is a plain-bearing replacement for a frame that makes small correction angles. It is separate from a loom let-off transmission and from a continuously rotating fabric roller bearing.

Control friction and axial play without using the flange as a clamp
Supply steering-frame mass, web tension resultant and pivot-to-roller offset. Describe correction angle, frequency, dwell and the force available from the actuator. Stick-slip or excessive axial freedom can affect response, so include the acceptable installed clearance and breakaway behaviour specified by the machine designer rather than requesting a tight fit without a tolerance.
QSn4-4-4 is the customer-specified tin-bronze material label for this enquiry. Confirm the exact designation, chemical specification, governing standard, delivered product form and condition before quotation. Do not infer a wrought or cast route from an informal grade label, and do not substitute ZCuSn10P1 or an overseas grade without approval. This smooth-bore, un-plugged construction uses the specified lubricant. The flange can locate the sleeve and provide a reviewed contact face, but should not be squeezed until the frame cannot articulate.
Application boundaries to confirm
The bearing alone does not guarantee fabric tracking accuracy. Sensors, actuator tuning, roller geometry and web traction remain part of the machine design. Assess lubricant escape and lint accumulation; no non-marking textile or lubricant-free performance is promised from the alloy designation.
Dimensions and drawing-based quotation checklist
| Review item | Information required |
|---|---|
| Steering pivot | Bore/OD, sleeve length, flange diameter/thickness and contact annulus. |
| Response requirement | Correction angle and rate, actuator force, web tension, offset and allowed end play. |
| Material and lubrication | QSn4-4-4 standard/condition, shaft finish, lubricant and fabric protection. |
| Procurement | Drawing revision, quantity, mating dimensions, worn areas and required inspection points. |
Identify metric or inch units and distinguish worn sample measurements from intended new-part dimensions. Include the mating-part drawing and requested material or dimensional documents; their scope and availability are confirmed with the quotation.
Installation and selection checks
Clean lint from the seats and inspect the shaft finish. Measure the fitted bore and set axial clearance with the approved shoulder or spacer arrangement. Cycle the empty steering frame before applying web tension, then check response using the machine manufacturer's procedure.
Frequently asked questions
Is QSn4-4-4 a cast-bronze substitute?
Do not treat it as one. Its product form, condition and standard need to match the purchase drawing.
Should the flange be tightened to remove all end play?
Use the specified axial clearance. Clamping the moving frame against the flange can raise friction or prevent correction.
Can this page predict tracking precision?
No. Provide the required motion and bearing fit for review; the complete web-guide system controls tracking.
Request a drawing-based replacement quotation
Send the drawing and duty to BONIU, identifying QSn4-4-4 tin bronze (designation and product form to confirm), quantity and revision. Material route, fit, manufacturing feasibility and inspection scope are reviewed before the quotation is confirmed.