"Flame-cleaning" the exterior of a spillway drum gate, preparatory to the application of four coats of paint. Eighteen acres of metal surface stared welders in the face when they recently began cleaning the interiors and exteriors of the 11 giant drum gates in the crest of the Grand Coulee Dam spillway, a third of a mile wide, in preparation for applying four coats of paint. Four and one-half to five acres of exteriors are being cleaned by a unique method known as "flame-cleaning. Welders armed with T-shaped torches, shooting intensely hot acetylene flames of 5300 degrees Fahrenheit, cover every foot of metal to remove rust and scale. Six-inch strokes are made at the rate of 20 to 30 feet per minute. The heating is so rapid that only the top layer of the tiny scales is raised to a high temperature, the bottom portions remaining relatively cold. The scales at once become brittle and fly loose.
Description
"Flame-cleaning" the exterior of a spillway drum gate, preparatory to the application of four coats of paint. Eighteen acres of metal surface stared welders in the face when they recently began cleaning the interiors and exteriors of the 11 giant drum gates in the crest of the Grand Coulee Dam spillway, a third of a mile wide, in preparation for applying four coats of paint. Four and one-half to five acres of exteriors are being cleaned by a unique method known as "flame-cleaning. Welders armed with T-shaped torches, shooting intensely hot acetylene flames of 5300 degrees Fahrenheit, cover every foot of metal to remove rust and scale. Six-inch strokes are made at the rate of 20 to 30 feet per minute. The heating is so rapid that only the top layer of the tiny scales is raised to a high temperature, the bottom portions remaining relatively cold. The scales at once become brittle and fly loose.