METHOD OF WELD AIRTIGHTNESS TEST Russian patent published in 1999 - IPC

FIELD: civil engineering. SUBSTANCE: method is used in manufacture of metal insulation of underground ferroconcrete part of building reinforced with metal sheets from inside. Method includes the following operations. One side of weld is moistened with indicating penetrant, and penetrant developer is applied on opposite side. Defective places are determined visually by stains on developer. In this case, water content of concrete in zone near weld is measured regularly. Visual inspection of weld is performed as soon as water content of concrete reached at least 10-12% by mass. Solution saturating the concrete is used as indicating penetrant, and cement dust serves as developer. EFFECT: simplification of airtightness test and reduced net cost. 5 dwg