O-Rings & Seals
Every mould water line, cylinder and gearbox depends on seals. Standard O-ring sizes and the right elastomer keep them dry.
What are o-rings & seals?
O-rings are toroidal elastomer seals compressed in a groove to seal static or slow-moving joints; oil seals (rotary shaft seals) seal rotating shafts with a sprung lip. Both follow international size standards, so identification by cross-section and diameter (or shaft/bore size) is usually enough to supply a replacement.
Types of o-rings & seals
NBR (nitrile) O-rings
General oil and water service — the industrial default.
FKM (Viton) O-rings
High temperature and aggressive chemical resistance.
Silicone / EPDM rings
Food-adjacent, steam and weather duties.
Oil seals (rotary)
Sprung-lip shaft seals by shaft/bore/width.
How to select o-rings & seals
- Cross-section and inside diameter (or groove dimensions).
- Elastomer by fluid, temperature and standard compliance.
- Static vs dynamic duty — finish and hardness matter when moving.
- Quantity — seals are consumed at every service.
Not sure? Send what you have — a part number, drawing or photo — and our engineering team will confirm the selection.
Frequently asked questions
- How do I identify an O-ring for replacement?
- Measure the cross-section thickness and the inside diameter — these map to standard size charts. Add the fluid and temperature so the correct elastomer (NBR, FKM, silicone) can be confirmed.
- When is FKM/Viton worth it over NBR?
- Above roughly 100–120 °C continuous, or with aggressive chemicals and fuels, FKM's temperature and chemical resistance outlasts NBR many times over — worth the premium wherever nitrile hardens and cracks.
Related components
Mould Cooling Components
Cooling decides cycle time. Baffles, plugs and nipples route water through the mould so every cavity region holds the right temperature.
Plungers
Plungers give machines a sense of position — the click of a detent, the hold of a spring-loaded ball, the lock of an index pin.
Washers & Shims
Millimetres are set with washers and shims — the small parts that give an assembly its exact heights, gaps and preloads.
Need o-rings & seals?
Tell us the specification, quantity and application — or just send the drawing.