| 摘要 |
FIELD: erection of horizontal, inclined and vertical high-pressure pipe lines in oil-producing, coal mining and other industries. SUBSTANCE: metal projections are welded on external surface of pipe ends; hardness of metal of projections is higher than hardness of metal of sleeve ; projections run into metal of sleeve; profile of projections has form of triangle or trapezium. EFFECT: enhanced strength of joint. 2 cl, 2 dwg
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