Failure Mode 1: Over-Stroke
Without stopper rings, the ejector plate can travel beyond design intent. Over-stroke bends long ejector pins, damages slide cores, and cracks thin-wall mold inserts.
Failure Mode 2: Under-Stroke
Without proper spacer rings and stroke calibration, parts don't fully release from the cavity. This causes stuck parts, robot arm errors, and cycle interruptions.
Failure Mode 3: Contamination
Without ejector space covers, machining chips and coolant enter the housing. Chips wedge between the ejector rod and its bore, causing binding. Coolant corrodes steel surfaces. Both lead to premature failure.
The Prevention Package
A properly managed ejector space uses all five component types together: KO rods for reliable force transfer, stopper rings for travel limits, spacer rings for correct spacing, stroke collars for adjustment, and covers for protection.