I have 160 metres of 6" st/st metric pipe installed in a straight line,could anybody help me with the expansion rate of the pipe given the highest temperature it will see is 20 degC
If you installed the pipe when it was 20 deg C then at 20 deg C it won't see any relative expansion. You need to take the temperature difference from ambient and not the absolute temperature to calculate expansion. The expansion could be anything.
Have to agree with corus, if the pipe is installed at an ambient temperature of 20 degrees, the movement will become +/- 13mm. The change in length given in my previous post is for the whole 10degC range. The Engineering toolbox site is a useful design site,