Ejector sleeve retainer plates and clamp blocks, made to your drawing. The parts that hold an ejector sleeve — or the core pin running through it — in the correct axial position within the ejector plate stack. Send a drawing, a sketch with the sleeve and pin sizes, or the existing part photographed against a caliper, and we quote in writing, normally within one business day.

What has to be held, and against what

An ejector sleeve assembly has two parts that move differently: the sleeve, which travels with the ejector plates, and the core pin inside it, which is normally anchored to the fixed side and stays still. The retainer's job is to hold one of them positively while the other passes through.

Two consequences follow:

• The retained shoulder must be fully captured, with clearance in the right places. A sleeve head trapped with no axial float will bind as the plates and the sleeve grow at different rates once the mold is hot. Normal practice leaves a small controlled float — tell us the working temperature and we will allow for growth rather than quoting a cold fit.
• The retained part must not be able to rotate. A sleeve free to turn wears its bore and, on any non-round core, destroys the moulded feature. If your sleeve or pin needs orientation, say so — it changes the retention feature, not just the dimensions.

The clamp face is a wear surface, not just a fastening

Every cycle, the retained shoulder loads the clamp face. If the block is too soft, the shoulder beds into it and the sleeve's axial position drifts; if the clamp is not flat, the load concentrates at one edge and the shoulder deforms. Both show up as a sleeve that gradually stands proud or sinks relative to the core — which is a witness ring on the part, usually blamed on the sleeve.

Give us the flatness you need on the clamping face and the hardness you want, or describe the cycle rate and we will propose them.

What to send us

• Block or plate length, width and height
• Bore, slot or clamping geometry, and which component is retained — sleeve or core pin
• Ejector sleeve outside and inside diameter, and the core pin diameter passing through
• Retained shoulder or head dimensions, and the axial float you want
• Whether orientation has to be held, and how
• Screw size, thread, counterbore depth and centre distances
• Mounting direction, mating plate drawing, operating temperature
• Material, hardness, tolerance, quantity and destination

Replacing one because a sleeve moved? Tell us how it moved — stood proud, sank, or rotated. Each points at a different cause: bedding-in, insufficient float, or a retention feature that never held orientation in the first place.

Documentation and confidentiality

Material certificates, hardness results and dimensional inspection reports are available on request, with scope and cost confirmed in the quotation. Technical files are used to evaluate and fulfill your inquiry or order. They may be shared only with relevant manufacturing, inspection, logistics or service partners as needed. Send only files you are authorized to share. See our Privacy Policy. NDA on request from rfq@privleymold.com.