Sometimes the corrosive resistance of AISI 316 acid resistant steel is challenged by highly aggressive chemicals (e.g. hydrochloric acid HCl). Then it is necessary to use either very expensive couplings made of special nickel-based alloys (e.g. Hastelloy) or less expensive couplings lined with ECTFE. The last couplings are made of AISI316 steel however all inner surfaces in contact with the medium are powder coated with ECTFE lining.

STORZ symmetrical couplings were designed in 1882 by Guido Storz and patented in Switzerland in 1890. In many European countries they became the standard couplings for fire fighting hoses and equipment. Hence STORZ coupling is popularly called a fire fighting coupling or fire hydrant coupling. Today it is widely used in fire protection systems, but also as a coupling for general industrial application for liquid and dry loose substances in the chemical industry, food industry, agriculture, construction, irrigation systems and sewage transport, in road tankers for loose bulk substances, etc.

GUILLEMIN couplings are intended for application in industrial installations transferring, loading and unloading liquid and dry loose substances. The couplings were first designed in France and are compliant with EN 14420-8 / NF E 29-572. Simple and easy connection is the key to their popularity. Two identical halves with two lugs are closed just by putting them together with the seals facing each other and by turning the locking rings so that the lugs are securely engaged. To tighten the connection, turn the locking rings with a hook wrench for Guillemin couplings by 1/4 a turn.

Symmetrical couplings feature a symmetrical design of locking heads (both parts of the coupling are exactly the same – no distinction between a coupler and an adapter) Therefore they can be quickly and easily connected – by pressing both parts against each other and turning.