What is the correct procedure to adjust the tightness of leaking impellor shaft gland packing on a boiler feed pump?

Adjusting the tightness of leaking impellor shaft gland packing is a delicate procedure that requires careful consideration to prevent damage to the pump and ensure proper operation. The correct procedure involves adjusting the packing gland to achieve a slight leakage, which is generally accepted as a necessary operation to prevent overheating and excessive wear.

The method of adjusting the packing gland to be finger tight initially and then making further adjustments while the pump is running allows for a controlled approach to achieve a consistent drip. This means that the packing is tight enough to prevent excessive leakage, but not so tight that it causes friction, overheating, or excessive wear on the shaft. A steady drip indicates that the packing is effectively sealing while allowing enough lubrication to keep the running components cool.

Replacing the packing immediately would not only be unnecessary in many cases, but it would also require disassembling the pump and could lead to increased downtime. Tightening the gland until no leaks are visible can create excessive pressure on the shaft, leading to overheating and potential damage. Adjusting while the pump is off does not allow for accurate assessment of the packing's effectiveness under operating conditions, as the dynamics change when the pump is running.

Therefore, the procedure of adjusting until finger tight and then tuning it during operation to achieve a