Stopper Rings & Pins
Hardened steel components that limit ejector plate travel to a precise maximum distance — preventing over-stroke and pin damage.
Stopper Rings & Pins Products
Stopper Rings & Pins — Type A
SUJ2 | HRC 58-62 | Precision ground
Stopper Rings & Pins — Type B
SUJ2 | HRC 58-62 | Precision ground
Stopper Rings & Pins — Type C
SUJ2 | HRC 58-62 | Precision ground
Stopper Rings & Pins — Type D
SUJ2 | HRC 58-62 | Precision ground
Stopper Rings & Pins — Type E
SUJ2 | HRC 58-62 | Precision ground
Stopper Rings & Pins — Type F
SUJ2 | HRC 58-62 | Precision ground
How Stopper Rings and Pins Control Ejector Plate Travel
Stopper rings are hardened steel discs or sleeves mounted on the mold base or ejector plate. When the ejector plate advances to its maximum designed stroke, the plate contacts the stopper ring, providing a positive mechanical stop that prevents further travel.
Stopper pins serve the same function but use a cylindrical pin format. They are preferred when space is limited or when variable stroke limiting is needed (by stacking washers on the pin shaft).
Both types must be hardened (HRC 58-62) to withstand repeated impact loading without mushrooming or deformation.
Learn more: For detailed technical guidance, see How Stopper Rings and Pins Control Ejector Plate Travel.
About Stopper Rings & Pins
Stopper rings and pins provide positive mechanical stroke limiting for the ejector plate assembly. They prevent over-stroke that could bend ejector pins, damage slide cores, or cause interference with the mold base. Manufactured from SUJ2 bearing steel at HRC 58-62 for maximum impact resistance.
Application Scenarios
Molds with Slide Cores
Over-stroke can push ejector pins into the path of slide cores, causing collision damage.
Why it fits: Stopper rings provide a hard mechanical limit that prevents the plate from advancing beyond the safe stroke distance.
Frequently Asked Questions
How do stopper rings limit ejector plate travel?+
What hardness rating do stopper pins have?+
Can stopper rings be stacked for variable stroke limiting?+
Engineering Resources
Need Custom Stopper Rings & Pins?
Precision stopper rings & pins manufactured to JIS and DIN standards. Custom dimensions available. MOQ 1 piece.