For seam steel pipes, the tolerance of the perpendicular angle between the end of the pipe and the axis is not more than 0.5. Pour a 0.2×45 break, and the connection port should be polished and smooth, and the surface should not have burrs and uneven surfaces. When bending the steel pipe, the length of the straight section from the end of the pipe to the bend should be greater than 2 times the length of the nut.
Coat the thread of the joint body and the ferrule with lubricating oil, spread evenly (do not stick to the tapered surface of the ferrule joint), and then tighten the nut repeatedly by hand to make the lubricating oil evenly spread on the nut thread.
Put the nut and sleeve on the seamless steel pipe. The direction of the ferrule cannot be reversed. Insert the pipe into the joint body (the pipe must be inserted to the end), and tighten the nut.
Tighten the nut evenly with one-handed wrench to the point of torque surge.
After reaching the pressure point, tighten the nut 1/2 turn again. Be careful not to rotate the steel pipe when tightening the nut.
Pre-installation should leave a margin (double ferrule joints do not need to be pre-installed), and the ferrule cannot be completely embedded in the pipe, so that the pipe is subjected to tensile stress. Remove the pre-tightening nut and check whether the steel pipe is at the front end of the ferrule An obvious protrusion is formed, and the leading edge of the ferrule has been covered by more than 50%. The ferrule can be rotated slightly, but cannot be moved axially.
Finally, the installation is completed, the nut is screwed to the point of torque surge, and then tightened about 1/4 turn, the installation is complete
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