[bug] aboveground pipes break when below height limit, w underground pipes below

if you bury pipes (eg 4 deep), the belts/pipes above ground can only reach 2 high (in this example), otherwise they will sometimes collapse.

savefile: https://drive.google.com/file/d/1qDVPql-Xvf33PCUShsnkRKZDAf-Y5rhY/view?usp=drive_link