Finishing

Corrosion steel and measures to combat it

Rivets are made mainly of steel stamps. 2 rivets (for structures made of carbon steels) and 09g2 (for structures made of low alloy steels).

The length of the rivets is set depending on the thickness of the cluttered package (capture) and the required diameter of the closing head.

Bolts for connecting steel structures are mainly used by black, clean and high -strength.

Black bolts (GOST 7789-57) are made by cold or hot stamping without a turn of the rod and head.

Bolts rod diameters are 10-24 mm (with gradation after 2 mm), 27, 30, 36, 42, 48 mm. Hexagonal bolts head; Its turnkey size, respectively, the diameter of the bolts is 17, 19, 22, 24, 27, 30, 32, 36, 41, 46, 55, 65, 75.

For black bolts, nuts are used according to GOST 5909-51.

Black bolts are manufactured with a stiting and without rehabilitation.

The use of bolts with stools for steel structures is not recommended.

Pure bolts with a hexagonal head (GOST 7815-57) and nuts for them (GOST 5926-51) are made in the second accuracy class with metric thread. Their diameters are equal: 10-24 mm (with gradation after 2 mm), 30, 36, 42, 48 mm. Turnkey bolt head size is the same as that of black bolts.

Washers are black in accordance with GOST 6957-54 and 6958-54 and clean in accordance with GOST 6959-54. They are designed to distribute efforts from the action of the nut and head of the bolt on a large area and to facilitate the twisting of the nut. The inner diameter of the washers is taken more than the corresponding diameter of the bolt by 0.5-2 mm. The thickness of the washers ranges from 2-8 mm depending on the diameter of the bolt. The outer diameter of the washers is about twice as much as internal. In addition to these, spring washers are used according to GOST 6402-52, which protect the nut from self-disclosure.

Black and clean bolts are made of Martenic carbon steel of the ordinary quality of stm. 3 and Art. 5.