WIKA USA’s Diaphragm Monitoring System

Submitted by Raimund Weissner || Wika

Measurement Solutions for Sanitary Applications

Sanitary industries, such as biotechnical, pharmaceutical, cosmetics, and food and beverage, are highly regulated to ensure certain processes comply with extremely strict hygienic requirements. To support operations and ensure product quality, measuring instruments in sanitary applications must provide accurate, reliable data — despite harsh process conditions. Pressure, temperature, and level measurement indicators must withstand high temperatures, aggressive cleaners, and extreme pressures. Failure to do so can lead to costly issues, such as off quality product and batch loss.

In these harsh conditions, pressure instrumentation is isolated from the process media by a diaphragm seal to prevent exposure to non-hygienic conditions. In seal assemblies, the process pressure is transmitted across a thin metallic diaphragm, and the system-fill fluid then engages the movement of the pressure indicator to provide a reading. However, with repeated exposure to extreme conditions the diaphragm foil can be damaged over time and fail. Should this happen, the system-fill fluid can potentially contaminate the process media. The troubling issue is operators aren’t able to detect a damaged diaphragm until a visual inspection is done, which could be long after the breach occurred. Without knowing exactly when the failure happened, you won’t know if previous batches may have been affected. Consequently, other batches must be quarantined back to the last known hygienic state. On top of lengthy delays, product may also need to be discarded. Of course, operational down time is also a concern in these instances.


Preventing Process Contamination: WIKA USA’s Diaphragm Monitoring System

To resolve this problem, WIKA USA designed the Diaphragm Monitoring System, which detects a failure when it occurs, helping prevent contamination and unplanned shutdowns. The system consists of two diaphragms with a hard vacuum between them. The vacuum is monitored with a pressure gauge, pressure switch, or pressure transmitter. If the primary diaphragm fails, the vacuum is compromised, and the monitoring system alerts the operator by giving a visual, acoustic or electrical warning. Since the secondary diaphragm still works properly, process integrity is not affected. Costly delays are avoided, and previous batches of product do not need to be discarded. Additionally, there is no need to stop the process immediately to make repairs. The patented Diaphragm Monitoring System is a prime example of WIKA USA’s solution-driven commitment to develop innovative technologies that support the needs of our customers.

Wika USA's Diaphragm Monitoring System