Boiler Feed Pump (5" diameter tensioners)

Introduction: Boiler feed pump discharge heads are one of the best applications for Superbolt® in a power plant. Boiler feed pumps are very critical components where time savings during installation and removal can save the plant lost hours of generation. Often Superbolt® Tensioners cost less than the replacement OEM nuts as the tensioners for these applications do not have to be made from expensive high temperature alloys.

Old Method: Heating Rods and large impact wrench (referred to as Big Bertha).

The old method of tightening was very time consuming, posed safety hazards, and required use of the overhead crane from the turbine deck. The crane time was particularly valuable during turbine outages. Two men operated the impact while one man operated the crane.

Solution: The installation was done using only two workers instead of three. Impacts were used followed by calibrated torque wrenches. Final torque was only 152 ft-lbs per jackbolt. Because the mechanics worked at 180° apart and followed a star pattern around the flange tightening in several steps, the gasket crush was very uniform throughout the procedure. This was verified by a field service technician from the pump company with feeler gauges.

This very large unit has only one boiler feed pump. If the pump should ever require an element change out forcing an unscheduled outage, the time saved removing the tensioners will save generation time.

Even worse, should a nut seize on a stud during an emergency element change out, stud removal can take up to 8 hours or more. With Superbolt® Tensioners, the main thread does not slide while under load so thread galling and seizure is eliminated.

 

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