Training and explaining the instrument to customers

A Comprehensive Analysis of the Causes of Negative Readings in Differential Pressure Leak Testing: Jingcheng Engineering Identifies Four Major Systemic Sources of Interference!

This article analyzes the causes of negative readings in differential pressure-based airtightness testing and proposes solutions. The article points out that negative readings do not indicate product leakage or instrument malfunction, but rather result from the pressure at the reference end dropping faster than at the test end, causing the pressure comparison between the two sides to be reversed. There are four main causes of negative values: micro-leaks in the reference component or aging seals; excessive differences in volume between the product under test and the reference chamber; pressure desynchronization on both sides due to temperature changes; and slight deformation of fixtures or tubing under pressure.