What is true about leakage when it comes to packing for pump sealing?

In the context of packing for pump sealing, an appropriate amount of leakage is considered a normal part of the operation. It indicates that the packing is functioning correctly; a small, continuous leakage helps maintain the desired sealing. This leakage serves to lubricate the packing material, cooling it and helping to prevent overheating, which can lead to wear or damage.

A slight amount of leakage is also essential for ensuring that the pump operates efficiently and safely. It prevents the packing from becoming completely dry, which can cause friction and lead to failure. Therefore, while it is not ideal to have excessive leakage, having some amount is beneficial and part of proper pump sealing practice. This balance ensures effective sealing while also prolonging the lifespan of the packing material.