www.joyetv.com

Prefabricated Steel Structure Workshop Building

96

Prefabricated Steel Structure Workshop Building

Prefabricated Steel Structure Workshop Building 1.Steel Structure Shot Blasting Specification National standard GB8923-88 “steel surface before painting Rust grades and preparation grade” good machining steel parts before painting methods commonly used shot blasting. Raw materials The grades of the unpainted steel surface are presented by A、B、C、D according to the coverage extent of the oxide layer and the serious degree of the spot erosion. Grade Sa1 Slight de-rusting through blast rust cleaning. The surface must be free of grease, dirt  and attached unfixed oxide coat, rust, paint coat and other attachments. Grade 2.5 Thorough de-rusting blast rust cleaning. The surface must be free of grease, dirt and attached unfixed oxide coat, rust, paint coat and other attachments. Any slight traces left are strip or spot-like light-color mottle. Grade Sad3 Stainless de-rusting thorough blast rust cleaning. No grease or dirty,  oxide coatin…