Pipe Connections Turbine

1. Steam inlet line

The main steam line should be anchored at the header, receiver or manifold. Always at the header and make the connection at the turbine lest.

The line should be sufficiently flexible so that no under strains are exeried on the turbine when at operating temperature.

This flexibility can be obtained by having the pipe of sufficient length with loops or section of piping at right angles to each other.

It should be properly supported throughout its lenght with the last support. but not an anchor located adjacent to the turbine.

 Spring hanger and rollers are recommended as support for the larger machines and especially large compared to that of the turbine.

At the point where the steam line connects to the turbine, make sure that the flange faces are parallel and that no force is necessary to bring them together or to match the bolt holes.

In order to reduce to a minimum the force exerted on the turbine by the expansion and contraction of the pipe the alignment of the flanges should be made with full steam pressure and temperature up to the throttle valve.

The final alignment is then make at then at the joint between the throttle valve and the turbine.

Before finally connection the steam line to the turbine it should be blown out thoroughly with high-pressure steam to remove any foreign matter such as dirty, scale, pip-joint-compound, etc., which if carried into the turbine, might prevent the closing of the governor valves and cause over speeding, or plug part of the nozzle area, thus reducing the capacity and efficiency of the unit.

It is of utmost importance to install a drain in the steam line at its lowest point between the header and the turbine.

2. Exhaust Line

The exhaust line should similarly be provided with adequate inherent flexibility.

If space limitations prohibit this, the pipe should have a flexible-cooper expansion joint placed to the turbine.

The exhaust pipe should be anchored just beyond the expansion joint to prevent the pipe thrust from damaging the expansion joint or the turbine. 

Even though an expansion joint is used, the same care should be exercised in aligning the pipe flange to the turbine exhaust flange ad described for the main steam line.

Be sure that the expansion joint is made of material sufficiently light to provide flexibility. Some expansion joints are so stiff that their use is of little value.

Whenever the turbine coupling is to be aligned or the alignment checked, be sure to disconnect the main steam line and exhaust line in order to eliminate the possibility of these pipes exerting excessive starins on the turbine.

When reconnecting them, be sure that the faces can be made parallel and the bolt holes matched without using force.

After the steam and exhaust pipes have been reconnected the unit should be heated up to approximately normal operating temperature and then the bolts should be removed from the pipe connections to check whether or not any excessive spring of the joints takes place.

If so, the condition should be corrected before the machine is placed in operation.