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Problème avec les membranes de vos pompes pneumatiques?

13/06/2023

Air-operated double diaphragm (AODD) pumps have become the preferred choice for various industries thanks to their versatility, reliability, and ease of maintenance. These pumps are widely used for transferring fluids, from light to viscous, in applications such chemical operations, waste treatments, food processing and ultra-pure transfers.

AODD pumps are subjected to stress and wear, parts in contact with the liquid can face issues even failure. The most common issues are related to diaphragms.

Membranes, a core part of the pump, are directly in contact with air and liquid. Depending on the operations, they can be under stress and used at their maximum capacities, or simply be not configurated properly. By facing various challenges, it leads to reduced performance, increased downtime, and costly repairs.

Understanding and troubleshooting these common membrane issues are essential for maintaining optimal pump efficiency and prolonging its service life.

Check the following table for a fast and smart way of troubleshooting your pump's diaphragms:

ISSUE	SYMPTOM	POSSIBLE CAUSE	SOLUTION
Abrasion	A worn-out ring on the liquid side where diaphragm mets center disk	The issue could be caused by fluid velocity and the presence of solid particles left inside the pump during shutdown.	Adjusting fluid velocity helps reduce friction and pressure on the diaphragm, mitigating abrasion. Preventing solid particle settling minimizes wear and tear of the ring.
Dry Running	Diaphragm failure, star pattern, or shortened lifespan	The pump is being operated without sufficient liquid.	Ensuring sufficient liquid prevents excessive stress on the diaphragm, preventing falures and prolonging its lifespan.
Excessive heat or chemical attack	Bubbling, cracking, discoloration, and material detachment.	The diaphragm material used may not be suitable for the specific application.	Choosing a suitable diaphragm material that can withstand the heat and chemical exposure ensures optimal performance and prevents material damage.
Excessive suction side pressure	Imploded or misshaped diaphragms.	High inlet pressure.	Dampening the inlet helps regulate the pressure, preventing excessive stress on the diaphragm and maintaining proper pump operation.
Over Pressurization	Bloating and diaphragm failure.	There is a significant pressure difference between the incoming air and the liquid discharge pressure.	Operating the pump within the recommended speed and pressure limits ensures balanced pressure distribution, preventing diaphragm bloating and failures.
Over Torque	Diaphragm cut along the outer edge has been observed.	Over-tightening of bolts and pump chambers cutting into the diaphragm.	Follwoing recommended torque values prevents excessive force on the diaphragm, preserving its integrity and preventing cuts from pump chamber intrusion.
Under Torque	Diaphragm pulling, "out of round" or oval shape is noticed.	Insufficiently tightened bolts.	Properly torquing the bolts ensures a secure diaphragm fit, preventing pulling and maintaining its desired shape throughout the pump's operation.