In which direction steam hammer load will be applied in COLD REHEAT PIPING, either flow direction or towards critical equipment (turbine) direction.

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Now to answer your question: The steam hammer load should be applied to neither directions. In fact, there shouldn't be any steam hammer loads applied to the Cold Reheat piping because the steam hammer loads come from the sudden closure of the Main Stop Valves (MSV) on the Main Steam Lines in an event of a turbine-trip. So these forces should be applied to the Main Steam (sometimes called High Pressure Steam) line at the elbows in the direction opposite to flow. The Cold Reheat line may be indirectly affected by the steam hammer loads in the Main Steam line only because they are interconnected by the HP-Bypass; otherwise, there are no direct steam hammer loads in the Cold Reheat Piping.

I hope this answers your question.

At the load direction i am not agree with you.
If a valve stop a flow, then a pressure wave to run trough the pipe.
Higher pressure then allways are first in flow direction and the lower pressure are oppostite of the flow.
The force is a product of delta pressure in the pipe leg, so the force direction are in flow direction.
Later maybe reflection pressure waves with opposite force direction.
But reflection pressure waves never so high as the first pressure waves, because friction to exist between pipe and flow.

i agree with ohliger...

for main steam and hot reheat piping applying hammer load towards flow direction.

but my question is for cold reheat piping..

some peoples are applying hammer load opposite to flow direction in cold reheat piping only ...

This is a other case.
If steam flow in a cold pipe, then can the steam condense and the pressure
decrease in this pipe section. Then the direction is opposite the flow direction.

I too agree with Ohlinger's first thread on hammer load direction should be in the flow direction. When there is sudden stoppage of flow,fluid becomes stagnant and kinetic energy gets converted into pressure energy and that zone (stagnant portion) experience sudden rise in pressure. Then the reflection wave.

but still i am not clear in CRH hammer load direction....

i hope that, there will be some technical reason for applying load in opposite to flow direction in cold reheat pipe........

In the most cases is the force direction not significant, because the moment and force results from dynamic +/- superpose with the static moments and forces at the supports.
For the stress in the pipe (example ellbow) it is also not significant, because we must respect the reflection case with the other direction.
I think the force direction is more importent at a real time hostory analysis and not at a modal time history method.