Foaming Issues in THI®F-502 PAG Quenching Fluid

(1) Causes and Analysis of Foaming in THI®F-502 Quenching Fluid

Foaming may occur during the use of quenching fluid for multiple reasons, including factors inherent to the fluid itself, improper operating procedures, excessive drag-out on workpieces, or air entering the system during circulation. Different causes and severities of foaming require different solutions.

①    Causes Related to the THI®F-502 Quenching Fluid Itself

These causes do not refer to product quality issues, but rather the inherent composition of the quenching fluid. The main components of quenching fluids are polymer materials, essentially surfactants. Over time, and under high operating temperatures, combined with some degree of drag-out, foaming can gradually increase. When excessive foaming occurs, adding fresh quenching fluid will often eliminate the foam because new fluid contains active defoaming ingredients.

Most additives responsible for defoaming gradually deteriorate during use and lose their effectiveness. Therefore, the defoaming technology used in the formulation should be considered a core component of quenching-fluid technology. This is often an overlooked performance indicator when selecting a quenching medium, which results in frequent addition of Defoamers during actual use.

② Air Entrapment in the Circulation System

If sudden or excessive foaming occurs, the entire circulation system should be inspected for air entry. Possible causes include air intake through the pump or a return pipe that is not fully submerged below the liquid surface.

(2) Method for Adding Defoamer

This defoamer is a dedicated additive designed specifically for THIF-502 quenching fluid. It offers strong defoaming performance. The dosage should be adjusted based on the severity of foaming. Start by adding 20 mL, distributing it as evenly as possible across the surface of the quenching bath. Add more as needed until the foam disappears or is reduced to a level that does not affect operations.

If you encounter any issues during use, please contact us.

Tags:Foaming Issue, PAG Quenchant, Defoamer, Antifoam, Quenching Problems, Foam Control, THI F-502, Honorhonest, Heat Treatment Stability, Quenchant Maintenance