The salt spray testing machine is used to simulate marine or high salt spray environments and evaluate the corrosion resistance of materials. Daily maintenance is the key to ensuring testing accuracy and equipment lifespan. The following provides detailed guidelines from three aspects: nozzle cleaning, saltwater replacement, and system maintenance:
1、 Nozzle cleaning: prevent blockage and ensure even mist particles
Daily inspection and dredging
After the test is completed, use a soft bristled brush or compressed air (pressure ≤ 0.2MPa) to clean the residual salt scale at the nozzle mouth to avoid crystal blockage. If uneven dispersion of mist particles or reduced mist output is found, the nozzle (usually threaded connection) needs to be disassembled, soaked in 5% dilute hydrochloric acid for 10 minutes, and then rinsed clean with pure water.
Regular deep cleaning
Soak the nozzle in an ultrasonic cleaning machine (frequency 40kHz) every week, add neutral cleaning agent, and run for 15 minutes to remove small particles. After cleaning, it is necessary to use a calibration plate to verify the diameter of the mist particles (standard value 1-5 μ m). If the deviation exceeds ± 20%, the nozzle needs to be replaced.
2、 Salt water replacement: control concentration to avoid contamination
Specification for saltwater preparation
Prepare 5% ± 0.1% saline solution (mass fraction) using analytical grade sodium chloride (NaCl content ≥ 99.5%) and distilled water, and verify with a concentration meter after preparation. Prohibit the use of tap water or industrial salt to prevent impurities from affecting test results.
Replacement cycle and operation
Replace the saltwater every 200 hours or after each batch of testing. When replacing, first drain the old liquid, rinse the salt water tank with pure water three times, and then inject new salt water. If testing highly corrosive materials (such as galvanized parts), it is necessary to shorten the replacement to every 100 hours to prevent concentration deviation caused by the accumulation of metal ions.
3、 System maintenance: Extend equipment lifespan
Box and pipeline cleaning
Wipe the inner wall of the test box with a soft cloth every month to remove salt stains; Rinse the saturated air tank and pipeline with pure water to prevent salt scale from blocking the air path. Check if the drainage valve is unobstructed to avoid the accumulation of water and the growth of bacteria.
Key component inspection
Check the accuracy of heating tubes, humidity sensors, and pressure gauges every quarter. If the surface of the heating tube is scaled (thickness>1mm), it needs to be sanded or replaced with sandpaper; Sensor deviation exceeding ± 2% requires calibration.
Maintenance shutdown
When not in use for a long time, empty the salt water tank and the liquid in the pipeline, blow dry with compressed air, and apply rust proof oil to the nozzle. Before reactivation, a 2-hour no-load operation is required to verify that all systems are functioning properly before testing.
4、 Precautions
Wear protective gloves and goggles during operation to prevent saltwater splashing from corroding the skin.
Maintenance records should be detailed with dates, operation contents, and replacement part models for easy traceability of issues.
Regularly contact the manufacturer for annual maintenance (such as replacing sealing rings and verifying control instruments) to ensure that the equipment meets the requirements of ISO 9227 and other standards.