Diaphragm Life
Industry Served: Chemical Process
Problem:
A manufacturer of metal soup cans located in New Jersey uses (8) 2" air diaphragm pumps to transfer the product which is used to line the cans. The suction of the pump is attached to the bottom of a 35' tall tank. The air operated diaphragm pumps are fitted with expensive PTFE diaphragms. The diaphragms were failing prematurely which resulted in loss of product, excessive downtime, and expensive part replacement. Additionally, leakage was occurring at the pump's clamping bands and the pumps were noisy during operation.
Solution:
After reviewing the pump's inlet conditions, it was determined that the 35' tanks created excessive inlet pressure. Air operated diaphragm pumps are not designed to handle high inlet pressure above the 10 psi maximum for PTFE diaphragms. This high inlet pressure also caused the pump's inlet valves to work harder to close which resulted in damaging pump vibrations and excessive noise.
After explaining to the customer that a Blacoh Inlet Stabilizer installed at the pump inlet would cushion and absorb the pressure spikes created by the higher inlet pressure, he was still skeptical. Watching the Blacoh demonstration that was provided proved conclusively that the high inlet pressure was damaging the pump's diaphragm.
A BLACOH model J2400T stainless steel inlet stabilizer was installed at the pump's inlet.
Result:
Flow into the pump is now smooth and pulse-free. Diaphragm life is much longer and pump operation noise is greatly reduced. They were so pleased that a second stabilizer was ordered.
Diaphragm Life
Industry Served: Chemical Process
Problem:
A nationally recognized manufacturer of quality paints uses air operated double diaphragm (AODD) pumps in process and transfer applications. In this application, the AODD pumps are used in a tank storage area to transfer Texanol, a solvent-based paint additive, to the production facilities within the plant. The AODD pump sits at the bottom of a 20' high Texanol storage tank. The inlet ball valves of the pump open and close several times per second. Each time the ball valve is closed or "seated", the fluid velocity is abruptly stopped. This creates high pressure spikes or "water hammer". The force of the spike severely weakens the integrity of the PTFE diaphragms by distorting their shape with unbalanced pressure loads and concentrating stress onto one area of the diaphragm, causing cold flow. The diaphragms were lasting only three weeks before failure. Every time a diaphragm failed, production halted and solvent was spilled into the containment dike and lost.
Solution:
A Blacoh SENTRY inlet stabilizer was installed on the inlet side of the pump to cushion and absorb the water hammer spikes created when the pump's inlet ball valves close. When the pressure spikes are cushioned, the effect of high acceleration head is diminished and the stress is removed, resulting in increased diaphragm life.
Result:
The Blacoh inlet stabilizer has been installed for over one year. In that time, the pump has not had a diaphragm failure and additional units have been installed on other AODD pumps in the tank storage area.
Diaphragm Life
Industry Served: Chemical Process
Problem:
A major international chemical company in New Jersey uses 3” air operated double diaphragm (AODD) pumps with PTFE diaphragms to pump a highly aggressive chemical through candle filters from an overhead tank. Part of the filtered chemical is recirculated at 30 psi back to the pump’s inlet. Rapid diaphragm failure was occurring in the AODD pumps. These pumps are generally limited to a maximum inlet pressure of 10 psi when equipped with PTFE diaphragms. As a result of the excessive inlet pressure, the PTFE diaphragms in these pumps lasted only a few hours.
Solution:
A Blacoh distributor was asked to find a solution to the rapid diaphragm failure problem. After consultation with Blacoh, a decision was made to install a 5 gallon Blacoh SENTRY inlet stabilizer at the inlet to each AODD pump. The inlet stabilizer acts as a shock absorber to cushion the water hammer pressure spikes created as the pump’s inlet valves rapidly open and close. The SENTRY inlet stabilizer uses compressed air, separated by a PTFE diaphragm from the process fluid, to balance pump inlet pressure and provide a smooth and continuous flow of liquid to the pump.
Result:
After SENTRY inlet stabilizers were installed, pump diaphragm life was extended from hours to more than 6 months. The SENTRY inlet stabilizer paid for itself in the first two weeks of operation.