C93700 Replacement Bushings for Paper-Roll Lifter Pivots
For a paper-roll lifter whose pivot drawing specifies C93700, request a replacement sleeve quotation with the pin and housing inspection results. The enquiry addresses an intermittently moving arm pivot with substantial loaded dwell. It is separate from the rotating roll chuck, reel spindle or pneumatic actuator rod guide.
Describe loaded dwell as well as lifting movement
A roll-handling arm can remain loaded while nearly stationary, then reverse when the roll is placed or released. Report roll mass, centre-of-gravity offsets, pivot geometry, motion angle and cycle pattern. Show whether two sleeves share a pin and how their spacing supports the arm. Include any impact at engagement and the actual lubrication interruptions observed in service rather than classifying the whole duty as simply slow speed.
C93700 belongs to the high-leaded tin-bronze family. Its composition differs from C93200; the higher-lead family description is not permission to substitute between them. The quotation should preserve the selected alloy and casting standard. Even where the grade is being considered for boundary-lubricated service, supply pin hardness, surface condition and the replenishment method. Material selection cannot turn an uncontrolled loss of lubricant into an approved maintenance strategy.
Separate a sleeve repair from a lifting-system assessment
Define moisture, paper dust, cleaning agents and any corrosion on the old pin. The bearing enquiry does not establish compatibility with papermaking chemicals merely because the machine handles paper rolls. Inspect the arm, retaining system and housing geometry under the machine’s repair procedure. Lift capacity, fatigue acceptance and safety controls remain assembly requirements; no bearing life or allowable lifting load is inferred from the grade name.
Drawing and quotation checklist
Send a dimensioned new-part drawing with units and revision, the mating assembly and the following application details.
| Review item | Information to provide |
|---|---|
| Pivot sleeve | Bore, OD, length, paired sleeve spacing, chamfers and retention. |
| Pin inspection | Original diameter/tolerance, measured wear, straightness, hardness and surface finish. |
| Lifter geometry | Roll mass range, centre-of-gravity offsets, arm drawing and load at each pivot. |
| Lubrication and environment | Oil/grease specification, feed route, interruptions, loaded dwell and contamination protection. |
| Purchase definition | C93700 standard/edition, material restrictions, quantity, revision and inspection requirements. |
Installation and selection checks
Inspect the housing and pin before choosing standard or repair-size sleeves. Use the approved fitting procedure, then check installed bore and alignment between paired supports. Verify that the pin retainers secure the pin without restricting the moving arm. Establish lubricant delivery and confirm free movement using the machine’s maintenance procedure before a controlled return to service.
Frequently asked questions
Can C93200 be supplied under a C93700 order?
Not as an unapproved substitution. Keep the alloy callout, casting specification and acceptance criteria explicit; any alternative needs separate purchaser approval.
Do two old sleeves always have the same bore?
Not necessarily. Load sharing and alignment can produce unequal wear. Send the original drawing plus measurements for each position rather than averaging the worn dimensions.
Does more lead remove the need for lubrication?
No. This is a lubricated solid-bronze pivot enquiry. The operating mode, pin condition and service plan must still be reviewed for the specific assembly.
Request a drawing-based quotation
Send the drawing, C93700 high-leaded tin bronze specification, quantity and operating details through Contact BONIU. Include any required material documentation and inspection criteria. Material route, manufacturing feasibility and delivery are confirmed in the quotation.