Deterioration Issues of THI®F-502 Water-Based Quenching Agent

(1) Causes of THI®F-502 PAG Quenching Fluid Deterioration

① The main component of PAG quenching fluid is a polymer organic substance, and organic substances are prone to spoilage and deterioration.

② Contamination by oil or external impurities.

③ Prolonged inactivity (idleness) makes PAG quenching fluid vulnerable to anaerobic bacteria growth.

(2) Impacts of THI®F-502 PAG Quenching Fluid Deterioration

① Bacterial growth reduces the pH value of the fluid, thereby impairing its rust-preventive performance.

② Unpleasant odors are often produced during bacterial proliferation, affecting the working environment.

③ It may clog the filtration system and hinder the normal operation of the system.

④ Although darkening and foul odor have little impact on the cooling performance of the quenching fluid, they may interfere with the concentration measurement using a refractometer.

(3) Solutions to THI®F-502 Water-Based Quenching Fluid Deterioration

Deterioration is caused by anaerobic bacteria. By introducing air through circulating agitation during production, the foul odor will dissipate over time, and the fluid will revert to its original color. If the spoilage is severe and aeration alone fails to achieve sterilization, adding a small amount of bactericide can effectively kill the bacteria. As early as 2008, our company independently developed a special bactericide for quenching fluids, which can keep the fluid from deteriorating for an extended period. Even if deterioration occurs, the fluid can quickly recover after adding this bactericide.

The experiment shown in the figure below demonstrates the changes of bacterial colony test pieces after the addition of the special bactericide for quenching fluids. It can be clearly observed that after the bactericide is added, the bacterial colonies on the test pieces are significantly reduced, and the color of the fluid returns to normal.

Tags：Quenchant Deterioration, Water-Based Quenching Agent, PAG Quenchant Life, Bacterial Contamination, Quenchant Maintenance, THI F-502, Honorhonest, Heat Treatment Quality, Polymer Degradation