Heat Exchanger Leak Testing: How to Choose Between Pressure Drop, Differential Pressure, and Tracer Gas

The testing method should match the allowable leakage rate, product volume, cycle time, and on-site environment.

Jinglian Zhongrui Technology Team

Key Points Different airtightness methods each have limitations in sensitivity, speed, cost, and locating capability. First, define the failure risk and judgment criteria, then choose the pressure, stabilization time, and detection medium. Implementation Focus 1. Confirm working pressure, test pressure, and safety protection requirements. 2. For the pressure drop method, control temperature balance, volume changes, and fixture leaks. 3. For high sensitivity requirements, evaluate tracer gas and manage background concentrations. 4. Periodically verify the detection system using standard leaks or known samples. Verification and Closed Loop The status of measuring instruments, environmental conditions, product numbers, and original curves should be saved along with inspection results. Project Recommendations During scheme reviews, input conditions, target values, verification methods, and responsible persons should be recorded in the same traceable document; when changes occur, simultaneously assess impacts on design, manufacturing, and delivery.This approach can transform experience into stable and replicable engineering capabilities. Further reading: ISO 9001 Auditing Practices Group — Measurement Traceability: https://committee.iso.org/files/live/sites/tc176/files/documents/ISO%209001%20Auditing%20Practices%20Group%20docs/Auditing%20to%20ISO%209001%202015/APG-MeasurementTraceability2015.pdf ISO — The Process Approach: https://www.iso.org/iso/iso9001_2015_process_approach.pdf