Diaphragm valve

GEMÜ's 650TL diaphragm valve with a pneumatic actuator and integrated handwheel is designed for use in ring mains which can, if necessary, be closed from a central control system. Using it, manual sampling can be inhibited on a temporary basis.

To be able to check the quality of ultra-pure water, it is necessary to carry out regular checks at precisely defined measuring points in the individual distributor loops. Pharmaceuticals standards require that quality-related measurement variables such as bacteria count, conductance and TOC values be considered. This data is acquired from samples taken in the return lines of each of the individual distributor loops using sampling valves.
 
In some cases, it can be necessary to keep sampling valves closed in order to inhibit manual sampling. This would, for example, be the case if the water temperature in the loop after hot water sanitisation is so high that employees could scald themselves when taking samples. To prevent this, the sampling valves can be kept closed via a central control system and pilot valve until the water temperature has dropped to a safe level again. Only then are employees able to take samples.

Another possible scenario is as follows: if too many tapping points are simultaneously open, the pressure in the distributor loop will decrease and drop below a critical level. In this case, the master control system could intervene and inhibit sampling in the same way. The valves would not be released for manual operation until the pressure in the loop is again within an acceptable range.

For such purposes, the GEMÜ 650TL has a pneumatic actuator in addition to the integrated handwheel. The valve can be closed automatically via a central control system and pilot valve – regardless of the position the handwheel is in. This increases operational and system reliability.