The precision of liquid column manometer was described. The correct use method and error correction of U tube manometer and double tube differential pressure gauge were analysed.
叙述了液柱式压力计的精度，对U形管压力计和双管差压计的正确使用方法及误差修正做了简要分析。
2
SY1 series downhole pressure gauge is made of spring tube.
SY1型系列井下压力计，是一种弹簧管式井下压力计。
3
The main fuel tank must have all the following: a filler tube, a ventilation system, fuel pickup tube and filter, plus a gauge-sending unit.