Graphite Bronze Trunnion Bushings for Radial Water Gates

Radial gate trunnion bushings support the gate-arm pivot at the specified pin interface. A graphite-plugged copper-alloy sleeve is a construction to assess from the gate design, with material and lubricant selected for the exposure. This page is for a bearing-component quotation, with no project or gate-operating approval implied.

Review long dwell and the first movement under load
A gate may remain stationary under substantial reaction before a limited-angle movement begins. Sustained pressure, breakout friction, corrosion and pin deflection therefore need separate attention. Water chemistry and silt exposure vary by site. A generic bronze or JDB name does not establish submerged-service compatibility.
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 |
|---|---|
| Trunnion interface | Pin and housing diameters, length, support details, fitted clearances, retention and installation access. |
| Load and movement | Sustained and peak reactions, dwell time, operating angle, cycle frequency and breakout requirements. |
| Site and material | Water chemistry, immersion/splash pattern, silt, corrosion pair, exact alloy and solid lubricant specification. |
| Purchase specification | Drawing revision, quantity, units, exact material or composite specification, finish, inspection-document requirements and delivery destination. |
Selection boundaries and installation
Check alignment through the assembled trunnion supports and account for pin deflection in the bearing review. Protect the running surfaces during handling and fitting. Confirm seals, drainage, corrosion protection and the inspection plan with the gate designer. Allowable pressure, friction and wear criteria must be established for the actual specification.
Material and replacement approval
For copper-alloy parts, state the exact standard and grade required by the design. JDB/500# and geometry codes do not establish chemical composition. Do not treat different national alloy designations as interchangeable without checking their specifications. 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
Does a graphite insert make every bronze suitable underwater?
No. The alloy, graphite system, water chemistry and mating materials must be reviewed together.
Can a steady-load calculation cover opening after a long dwell?
The design should address both sustained contact and the first movement; provide the relevant load and friction requirements.
Are this page and a complete trunnion assembly the same offer?
No. Supply the assembly drawing and identify the bearing component and any additional parts to be reviewed.
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.
Related products and engineering content
Base product and construction · Material selection · Related machinery applications · Related technical reading · Product catalogue
Application reference: OILES radial-gate swivel-shaft bearing application. This reference supports the general mechanism or selection principle; its product ratings and approvals are not BONIU specifications.