ATEX and control units in mixer tanks

It is common in mixer tank deliveries that the design and construction of the control unit is left for the end user to be executed. When control unit is not in the scope of mixer tank, the mixer tank supplier is not possible to mark the equipment with a CE mark, as it is only a partially completed machine under the Machinery Directive. In other words, a declaration of conformity may be drawn up and the equipment can be CE marked only after the equipment is a complete machine in accordance with the Machinery Directive, which is including both the tank and the mixer as well as the control unit and safety equipment and all other possible subassemblies.

It is sometimes appropriate to replace electrical control components and functions for pneumatic operation in order to achieve an adequate level of protection in the presence of explosive substances. For example various chemicals used in pharmaceutical industry and different flammable substances used in the manufacture of explosives requires precise planning for the equipment and careful selection of components. In ATEX-classified facilities a correct equipment classification is required from the equipment and the operation of the entity must be assessed taking into account all safety aspects in order to ensure and guarantee a safe use of the equipment.

Tankki Oy has a full capability to design and supply also control units together with mixer tank deliveries. We have also implemented different control units to demanding ATEX environments. We have made Ex-equipment and their plans and documents relating to explosive substances together with various inspection bodies and experts. Many times the most important functions in the deliveries of ATEX equipment is HAZOP studies, ignition source investigations and final documentation preparation and they are always performed together with different experts, Tankki Oy and the customer. We design and manufacture the complete unit and produce necessary documentation, and the only thing customer needs to tell us is what kind of functions from the end user’s viewpoint needs to be considered.

Mikko Soinila, sales engineer