pure-internal pressure test

例句：

1. 1. The engineer conducted a pure-internal pressure test on the new engine.
   工程师对新引擎进行了纯内部压力测试。
2. 2. During the test, the pure-internal pressure was carefully monitored to ensure safety.
   在测试过程中，仔细监测纯内部压力以确保安全。
3. 3. The company insisted on conducting a pure-internal pressure test before shipping the product.
   公司在发货前坚持进行纯内部压力测试。