PTFE Composite Bushings for Packaging Sealing-Jaw Hinges

The bearing position considered here is the oscillating hinge of a sealing-jaw linkage. It is not a sealing strip, heater component or a bearing inside the heated jaw without thermal review. A tin-plated SF-1-F sleeve can be assessed from the hinge drawing when a thin-wall radial guide and flange fit the available space.

Silver-coloured flanged composite bushing with a split cylindrical sleeve — 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.

Separate the hinge duty from the hot sealing surface

Heater temperature does not directly define the bushing temperature. Conducted heat, dwell and thermal isolation determine the hinge environment. Cleaning agents and product debris introduce additional conditions. Suitability must be checked for the specified composite lining, backing and exterior treatment.

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
Thermal conditions	Measured or design temperature at the bushing, heater location, insulation and warm-up/dwell cycle.
Hinge motion	Closing force, pivot reactions, angular travel, cycling rate and permissible jaw-position play.
Environment and fit	Shaft/housing tolerances, flange dimensions, cleaners, washdown and any required compliance documentation.
Purchase specification	Drawing revision, quantity, units, exact material or composite specification, finish, inspection-document requirements and delivery destination.

Selection boundaries and installation

Protect the lining during pressing and check assembled running clearance. Review cold and warm conditions so the hinge neither binds nor permits excessive movement. Tin plating does not establish chemical resistance or food-contact compliance; specify any such requirement before an order is confirmed.

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.

The application description is a design-review starting point. No stock availability, service-life guarantee, machine approval, universal load limit or test result is claimed. Contact pressure, motion, temperature, counterface condition and the assembled load path must be checked for the chosen specification.

Purchasing questions

Can the maximum heater setting be used as the bearing rating?

No. State the actual bearing temperature and the required approved material limits.

Is this a food-contact certified bearing?

No certification is claimed here. Identify food-zone exposure and documentation needs explicitly.

Can a flange eliminate all jaw end play?

The permissible axial clearance and hinge stack must be set by the machine design.

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.