ALFEM Engineering
ALFEM Engineering

We Are The Machine Doctor

when it comes to acoustics, vibrations and dynamics.

FREQUENTLY ASKED QUESTIONS

This section is for people who are working in the mechanical or similar field and have questions to ask regarding a technical situation at work. If you need a second opinion or a confirmation to your theory on the cause of a problem, please feel free to drop us a line! Just send us an email with your name, occupation and company (optional). We will reply you shortly with our take on the situation.


When the pump in the mechanical plant room is switched on and off, there is always a “thug” sound. The pump works perfectly well without any unusual noise while in operation. There are isolators installed so does that mean they are not effective?

If the sound is heard during starting or turning off the pump, there is a high possibility that it is due to a “water hammer” effect. This is usually due to a sudden change in pressure in the pipeline. If not properly mitigated, it could cause serious damage to the pump and the pipeline.

The isolators installed would work sufficiently well during normal pump operations, but might not be able to withstand the impact from the surge. We would recommend that a detailed site analysis be done to determine the magnitude and seriousness of this surge and installing suitable pressure relief measures.