气密性实验主要是检验容器的各联接部位能否有走漏现象。介质毒性水平为极度、高度危害或设计上不允许有微量走漏的压力容器，必需停止气密性实验。
The air tightness test is mainly to check whether there is leakage in the connecting parts of the container. The pressure vessel with extreme toxicity level, high hazard or no trace leakage in design must stop the air tightness test.
压力容器应按以下请求停止气密性实验：
The pressure vessel shall stop the air tightness test according to the following request:
（1）气密性实验应在液压实验合格后停止。对设计请求作气压实验的压力容器，气密性实验可与气压实验同时停止，实验压力应为气压实验的压力。
(1) The air tightness test should be stopped after the hydraulic test is qualified. For the pressure vessel designed for pressure experiment, the air tightness experiment can be stopped at the same time as the air pressure experiment. The experimental pressure should be the pressure of the air pressure experiment.
（2）碳素钢和低合金钢制成的压力容器，其实验用气体的温度应不低于5℃，其它资料制成的压力容器按设计图样规则。
(2) Pressure vessels made of carbon steel and low alloy steel shall have gas temperatures not less than 5 C. Pressure vessels made of other materials shall follow the design rules.
（3）气密性实验所用气体，应为枯燥、清洁的空气、氮气或其他惰性气体。
(3) The gases used in the air tightness test shall be dry, clean air, nitrogen or other inert gases.
（4）停止气密性实验时，平安附件应装置齐全。
(4) When the air tightness test is stopped, the safety accessories shall be fully equipped.
（5）实验时压力应迟缓上升，到达规则实验压力后保压10分钟，然后降至设计压力，对一切焊缝和衔接部位涂刷肥皂水停止检查，以无走漏为合格。如有走漏，修补后重新停止液压实验和气密性实验。
(5) The pressure should rise slowly during the experiment, hold for 10 minutes after reaching the regular experimental pressure, then drop to the design pressure, and stop inspecting all welds and joints with soap water, so as to be qualified without leakage. If leakage occurs, the hydraulic test and air tightness test shall be stopped again after repair.
气密性实验与气压实验是不一样的。首先，它们的目的不同，气密性实验是检验压力容器的紧密性，气压实验是检验压力容器的耐压强度。其次实验压力不同，气密性实验压力为容器的设计压力，气压实验压力为设计压力的1.15倍。
The air tightness experiment is different from the air pressure experiment. First of all, they have different purposes. The air tightness test is to test the tightness of pressure vessel, and the air pressure test is to test the pressure strength of pressure vessel. Secondly, the experimental pressure is different, the experimental pressure of air tightness is the design pressure of the vessel, and the experimental pressure of air pressure is 1.15 times of the design pressure.
