Brush-On Polymer Seals Porosity in Welds

This high-performance brush-on methacrylate compound is formulated for sealing porosity in welds that will contain gases under pressure or liquids.

WeldSeal^™ from IMPCO, Inc. (East Providence, RI) is a high-performance brush-on methacrylate compound formulated for sealing porosity in welds that will contain gases under pressure or liquids. Its low dynamic viscosity enables this compound to wick deeply into pores and seams and between close-fitting ferrous metal surfaces. After WeldSeal has cured in the porosity or voids, excess material on the surface is easily rinsed away with water, leaving the surface clean and ready for painting or other operations. The compound does not alter critical surface dimensions.

WeldSeal comes packaged in a 250 ml kit with a shelf life of six to 12 months. Mixing the sealant’s two components creates a VOC-free, low-viscosity, pale blue liquid that can be easily applied by brush. Once mixed, the compound has an extended pot life of about one day, allowing multiple parts to be treated from the same kit. Drawing a vacuum improves penetration. The unique chemistry allows fast, easy cleanup of parts, tools, and brushes with water — no detergents or solvents are required.

Cured WeldSeal forms a pressure-tight mass that withstands continuous service temperatures of up to 179 deg C (355 deg F). In fact, parts treated with WeldSeal have been tested leak-free at over 150 psi. The cured compound has a typical hardness of 95 Shore D (ASTM D2240) and exhibits excellent resistance to a broad range of chemicals, including oils, glycol, chlorinated and fluorinated solvents, mild caustics, acid solutions, and water.

With more than 55 years of experience in porosity sealing, IMPCO offers materials, equipment, resins, and parts cleaning, impregnating, and pressure-testing services for permanently sealing (to industry and U.S. military standards) micro and macro porosity in metal and powdered metal castings, electronic components, ceramics, and various parts coated with micro-cracked nickel or chrome.

Specialists will optimize the impregnation process for components used in brake, transmission, instrumentation, pumping, compressed air and gas, pressurized spray, fire safety, and hydraulic systems. The company will also custom-engineer impregnation systems, providing customers with all the equipment, materials, and ongoing technical assistance they need to establish in-house impregnating processes. www.impco-inc.com