Mold Return Pins — Pack of 4
Standard-part returns: request authorization within 14 days after delivery; item must be unused, uninstalled, undamaged and in original packaging. Review the full return policy.
Need a non-standard size? Request a Quote →Return pins for injection mold ejector systems, sold in packs of 4 — the quantity a standard mold uses. Sizes are given as diameter × length in millimetres.
What they do, and why all four matter
Return pins push the ejector plate back to its home position as the mold closes, before the core and cavity meet. They work as a set of four at the corners of the ejector plate, and their job is as much about keeping that plate square as it is about returning it.
That is why we sell them in fours. Replacing one worn pin out of four leaves you with three worn pins and one tight new one, which cocks the plate slightly on every stroke — and a cocked ejector plate is what turns into bent ejector pins, galled guide bushings and a plate that sticks halfway. If one has worn enough to need replacing, the other three are the same age.
Length is not optional
The return pin face has to finish exactly flush with the parting line. Proud, and the pin holds the mold open a fraction — you get flash all round the parting line and, on a bad day, a damaged face when the machine clamps anyway. Short, and the ejector plate never fully returns, so the ejector pins stand proud into the cavity and the next shot mars or short-fills.
Measure the existing pin, or measure from the ejector plate seat to the parting face with the plate fully back. If you are working from a drawing rather than a tool, tell us the plate stack and we will confirm the length before shipping.
Check the springs at the same time
Return pins are usually fitted alongside ejector return springs, and a weak spring makes a good return pin look faulty — the plate does not start home, then the pins take the whole load at close instead of easing it back. If you are replacing return pins on an older tool, it is worth checking the springs in the same shutdown. See die springs.
Specifications
| Diameters | Ø12, Ø16 |
| Lengths | Ø12: 80–250 mm | Ø16: 100–140 mm |
| Pack quantity | 4 pieces — one mold set |
| Origin | Danyang, Jiangsu, China |
Larger diameters and longer pins
Ø15, Ø20, Ø25 and Ø30 are all stocked, in lengths to 500 mm — but a set of four Ø25 pins is several kilograms and does not belong on a flat parcel rate. Request a quote for those and we will price the freight properly against your destination rather than bury it in the item price. Tapped return pins are also available.
Shipping
International freight is calculated on packed chargeable weight. See Shipping & Delivery for destinations and transit times. Import duties and taxes are the buyer's responsibility — please read the duties section on that page before ordering.
- Material grade
- Confirm before ordering
- Hardness / load grade
- Confirm before ordering
- Surface treatment
- Confirm before ordering
- Key tolerance
- Confirm controlling dimensions before ordering
- Metric specification
- Diameter × length (mm)
- Package quantity
- 4 pieces per pack
- Single-piece weight
- To be confirmed
- Package weight
- To be confirmed
- Country of origin
- Danyang, Jiangsu, China
- Processing time
- Varies by specification; confirm before ordering when timing is critical
- International freight
- Quoted from packed chargeable weight; carrier transit time is estimated separately
- Typical application
- Returning and squaring the injection-mold ejector plate
- How to select
- Match pin diameter and the finished flush length at the parting line.
- Check before ordering
- Diameter, length, head geometry and flush position at full return
- Non-standard dimensions
- Submit an RFQ with a drawing, photo or measured dimensions