In pumps, mechanical seals are usually used to seal the equipment. Nonetheless, there are still a number that make use of compression packing for sealing purposes. These pumps are used across a wide range of industries and play a critical role in supporting various industrial processes.
Failure of compression packing as well as subsequent pump failure has been proven to disrupt process operations. This, in turn, has resulted in unexpected plant downtime and significant financial losses. Additionally, additional labor is required for cleanup in these situations. As such, it goes without saying that a pump user needs to be fully aware of the steps that ought to be taken to ensure smooth, efficient pump operations.
Packing failure can be caused by a number of different factors. Some of these are as simple as the wear and tear induced by normal operations. Moreover, the improper choice of materials and lubrication is also liable for mechanical damage and subsequent packing failure.
More often than not, adjustable packing can fail as a result of excessive gland tightening. The misalignment of plunger and pistons, as well as dirty or corrosive liquids or environmental factors can also contribute to packing failure.
Signs of Packing Failure
Packing failure can be detected by a number of different indicators. For instance, it’s common for failure to be accompanied by increased leakage. In other instances, users may no longer be able to control leakage, leaving the baseline drip rate unable to be regulated using normal gland follower adjustment.
Other signs of failure include smoke inside of the stuffing box, or packing protrusion outside of the pump. Furthermore, routine maintenance makes it possible to assess the state of packing material. This will help determine its state, whether brittle or otherwise.
In the event of packing failure, it’s essential to rectify the problem by removing the old packing and replacing it with new material. This then follows that the end users be familiar with the specific safety and environmental regulations involved. As such, any degraded material should be replaced, and the cavity and stuffing box thoroughly cleaned before repacking. Smaller parts that may be damaged should also be replaced before the plunger is reinserted with sufficient lubrication.