I'm working on subsea skid. There are several tubular supports on straight piping layout.

The concern is these tubular supports are welded on skid floor at bottom and support the pipe by clamping. There is neoprene material between the clamp and pipe. Can the pipe slide or will be fixed? Is it ok to ignore thermal force? Since the operating temperature is low 45degC.

You need to know the clamping force at the support, and apply it as a vertical load at the support with friction. You also have to CNODE that support and apply an equal and opposite force equal to the clamp force at the CNODE.

This effectively makes your pipe act like it's X lbs heavier, but only for purposes for friction.

Therefore, you won't need to neglect temperature.

Can you explain "pipe act like it's X lbs haevier, but only for purpose for friction"?

If the clamp force is big, will the pipe be deformed? The pipe itself has 1in thickness, quite thick. ID = 14.7in