Question 174General Subjects - 1st Asst/Chief

The correct answer is A) loosened, and then retightened with the pump running under normal conditions. The reasoning behind this is that when renewing spiral packing in a centrifugal pump stuffing box, it is important to ensure the packing is properly seated and compressed. After the new packing is firmly installed, the packing gland nuts should be loosened to allow the packing to adjust and conform to the shaft. Then, with the pump running under normal operating conditions, the gland nuts should be retightened gradually to compress the packing and achieve the proper seal. The other options are incorrect because: B) leaving the gland nuts in the tightened position after the new packing is installed would not allow the packing to properly seat; C) tightening the gland nuts an additional 10% could over-compress the packing and lead to premature failure; and D) loosening the gland nuts until the gland clears the stuffing box would result in an insufficient seal.