How to avoid pump mechanical seals failure in use

Tips to avoid seal leakage

All seal leakages are avoidable with the proper knowledge and education. Lack of information prior to selecting and installing a seal is the primary reason for seal failure. Before purchasing a seal, make sure to look at all requirements for the pump seal:

• How the seal equipment is specified
• Installation procedure
• Operational practices

If a pump seal fails, the same seal is likely to ultimately fail again in the future. It is essential to know the specifications of each pump seal, the pump, internal parts and any additional equipment, prior to purchase. This will ultimately save long term costs and pump damage. Below are the most important tips for preventing pump seal failure:

Proactive and preventative maintenance

The most effective way to avoid seal failure is to regularly check the pump for any faults or irregularities. Once the correct pump, seal and seal support systems have been selected and installed, proactive preventative maintenance is the top method to uphold seal reliability.

Data-driven maintenance has been proven to optimize pump performance and reduce failure, so it is essential to note the pump’s work history, repairs, process type and any manufacturer recommendations in addition to general check up.

While performing a maintenance check, start by assessing the equipment. The bearing frame must contain the correct oil level and the oil must not appear milky in color. If it is, this would indicate that the oil is contaminated, and may soon lead to bearing issues. It is important to also check the level of barrier fluid in the dual seal support system. If there is a drop in the liquid level, this indicates that there is an onboard seal leak.

Once these have been checked and repaired if necessary, assess the following:

• Suction pressure and discharge pressure gauges
• Temperature gauges
• The sound of the pump

These are all vital checks that will likely reveal if there is a problem with the pump seal, and in turn reveal the location and cause of the failure.

Design improvements

Though there are a range of preventative measures to keep existing pump seals from failing, another means of mitigating seal failure is to install an updated pump seal design. Newer designs have the advantages of better centrifugal pump efficiency and a variety of seal face materials that are engineered to withstand harsher chemicals and processes.

New seal designs also often offer optional components and upgrades. Older designs provided the best solutions at the time of installation, though today’s designs and material improvements provide far more reliable, lasting solutions. When deciding if a pump seal needs to be replaced or upgraded, prioritize any seals with a repair history that suggests declining efficiency or longevity.

Fixing a pump seal failure

If the seal has failed despite the above tips, collect as much data as possible to diagnose the problem and ensure that it does not occur again.

While troubleshooting a seal application, have on hand a range of useful tools such as a marker, notepad, camera, contact thermometer, watch/timer, inspection mirror, hex head wrenches, magnifying glass and anything else that might be deemed useful. With this equipment, use the following as a checklist to help identify the cause of the leak:

• Identify the location of the leak
• Note how much fluid has leaked
• Observe the leakage rate, and if any operating conditions change this
• Listen to see if the seal is making a noise
• Check the operating conditions of the pump and any seal support systems
• Look for any vibrations
• If there are vibrations, take readings
• Review the pump’s work order history
• Review if any other malfunctions or damage occurred prior to the seal failure


Post time: Mar-31-2023