Manufacturers of solenoid valves are faced with a choice. To buy a "standard, off the shelf" coil or to make your own.

A K Muller have always preferred the latter option.  We feel that only designing and building our own gives our coils the edge on the competition.

The magnetic and electrical characteristics for differing electrical supplies make it vital to have bespoke solutions for each valve

An increased amount of automation in the process has not only sped up production times but also enabled more quality checks to be included. At various stages in the production process automatic checks are made for resistance, inductivity, insulation strength and high voltage capacity.

Each coil is tested several times before it even reaches the rest of the valve.

Traditionally, A K Muller have used a Duraplastic insulation material to encase the copper windings. Over the past few years it has been noticed that the cost of this material has been rising at a greater rate than some equivalent products. The rises have been sufficiently marked to cast doubt on its future availability.  With this in mind our engineers have been trying to find alternatives that will be freely available but will not compromise the quality of the coil.

The answer is Thermoplastic. Not only does this plastic take around a fifth of the moulding time of duraplastic, it has a much longer shelf life and is accepted by the important electrical approval bodies.

There has been a heavy investment in injection moulding machinery for the thermoplastic coils and several of our ranges have been converted to this new material with others to follow.

A K Muller have always had many of our valves approved by UL and VDE as two of the most internationally recognized standards. Recent changes have extended the VDE approval through the ENEC scheme to include another nineteen partcipating countries.  At the moment this applies to the 7, 10 and 13mm valves in our range.