Pipe Strain Flashcards
what is pipe strain?
any unwanted movement in piping during operation which would affect a machines operation and cause premature failure
list 3 static loads in pipe strain
weight
thermal movement
foundational
list 6 dynamic loads in pipe strain
vibration
wind
water hammer
slug flow
PSV changeout
unaccounted process changes
what is the purpose of pipe supports?
to reduce the stress of the piping system
what is the ASME B31.3 tolerance for a flanged joint across any diameter?
0.0625
what tolerance measurement should bolt holes be aligned?
0.125
why is it important to measure flange movement at the flanges as well as the couplings?
flanges - actual movement
coupling - how the shaft is effected by the movement
if the axial distance between flanges is too large for a fit-up, what are 2 acceptable methods of correction?
orifice plates
welded spools
what is the purpose of a bellows or expansion joint?
to minimize pipe strain due to temperature or pressure changes
which type of flame bending yields the least amount of pipe correction movement?
spot method
what 3 types of movement must you consider when selecting the location of heat?
deflection
length
parallelism
in order, list the 3 steps for correcting pipe misalignment using the flame bending technique
length - both sides of the elbow
deflection - as far away from the flange as possible
parallelism - as close to the flange as possible
why is the vector alignment system rarely used for correcting pipe strain?
because the heat spots are rarely in places you can use heat bending
what does PSA stand for?
pipe strain analysis
what are the 4 axis points in a computer generated diagram?
x,y,z - pipe system
N - (north) compass orientation
