Pressure transmitters for food processing

The production and processing of food and beverages is governed by a rigorous network of laws, regulations, codes of practice and guidance. The aim of these rules and guidelines are to minimise possible risks to the consumer from potentially harmful products that result from the presence of foreign bodies or bacteria. The use of pressure instrumentation is an essential part of safe food production.

Pressure and level measurement in the food, dairy, beverage and processing industries is required in piping, filters and tanks. Pressure instruments must be accurate, immune to vibrations, able to withstand the temperatures and stresses generated by cleaning processes, and have specialised wetted parts. Applications include balance tanks, silos, storage tanks, mixing processes, flavour systems, pasteurisation, emulsifying, filling machines and homogenisation.

The majority of electrical pressure transmitters use a flexible diaphragm as the pressure transmitting element. By using the appropriate process connection, it is possible to produce flush mounted pressure transmitters that have no cavities and are easy to clean. CIP (Clean In Place) cleaning is utilized to clean the interior surfaces of pipelines and tanks of liquid and semi-liquid food and beverage processing equipment. This type of cleaning is generally done with large tanks, kettles or piping systems where there are smooth surfaces. The “wetted part” of a pressure transmitter is the diaphragm which is in contact with the medium being measured and must be able to withstand the forces and temperatures generated during CIP cleaning and sterilisation procedures. Regular cleaning and gap free design reduce risk of contamination, but the finish of the wetted parts must also have smooth contours and clean welding with no nooks and crannies that may cause the media to gather and rot. Usually components are made from stainless steel to prevent media from sticking.

The PT124B-217 flush diaphragm transmitters have been designed to meet the requirements of the majority of industrial food and beverage applications. Robustly constructed from stainless steel, this range of pressure transmitters offer excellent stability and accuracy over a long service life. The flush membrane are suitable for CIP and seals are available in a variety of forms that can be installed directly to the process or remotely via stainless steel capillary.