The nut must be screwed perpendicular to the axis of the screw

Update:14-08-2019
Summary:

The correct way of operation: (1) The nut must be screw […]

The correct way of operation:

(1) The nut must be screwed perpendicular to the axis of the screw, not to tilt;

(2) During the tightening process, the force must be uniform, and the force should not exceed the safe torque value (with the safety torque table);

(3) Use torque wrench or socket wrench as much as possible to avoid using adjustable wrench or electric wrench;

(4) It must be cooled when it is used in high temperature, and do not rotate quickly when using it, so as to avoid the sudden rise of temperature and cause locking (such as electric wrench, etc.).

Safety Torque Reference Table:

(1) Equipment used: torque wrench, bench vise, matching sleeve:

(2) Screw and nut performance grade; A2-70, 304 material, tensile strength: 700N/mm2, drop strength: 450 N/mm2;

(3) Working mode: vertically clamp the screw head on the bench vise, sandwich a piece of workpiece in the middle, a flat pad and a spring pad, and then apply a nut evenly to apply the force as the nut to the following. When the value is exceeded, the nut can no longer be smoothly unscrewed.

(4) Safe Torque Table: Unit: Nm Specification M20-2.5 M18-2.5 M16-2.0 M14-2.0 M12-1.75 Safe Torque 220 180 150 100 55 Specification M10-1.5 M8-1.25 M6-1.0 Safe Torque 40 40 9 Note The above data are obtained for the above experimental conditions and are for reference only. Actual data is affected by construction conditions, but the maximum should not exceed this torque.

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