There are some applications for O-rings that fall outside the standard sizes usually specified. These sizes may be:
- true imperial dimensions, so a 1/8" section is 3.17mm, rather than 3.53mm;
- for specific applications e.g. RJT couplings;
- for sizes between the normal run of standard sizes;
- for very small (Micro and Miniature O-rings);
- very large O-rings - Scarf Joined and Vulcanised O-rings (SJV O-rings).
Micro and Miniature sizes of O-rings are manufactured by a moulding method, whereas very large O-rings, depending upon the size, can either be made by joining O-ring cord; or for internal diameters less than 2500mm it is possible to mould in one piece.
Whilst an O-ring size may be non-standard there is a good probablity that mould tools have already been developed, so please contact customer services with details of the size you require.