1. Pipe breaking: Draw a line on the selected galvanized steel pipe according to the on-site surveying and mapping sketch, and break the pipe according to the line.
a. Use a grinding wheel to saw off the pipe. Place the pipe on the grinding wheel saw caliper, align it with the drawn line and clamp firmly, then cut the pipe. When cutting off the pipe, press the handle with even force and do not use too much force. After cutting off the pipe, clean the iron film and burrs on the section of the pipe mouth.
b. To cut off the pipe with a hand saw, the pipe should be fixed in the pressure clamp of the pressure case, align the saw blade with the drawing line, push the saw with both hands, the saw blade should be kept perpendicular to the axis of the pipe, the force of the push and pull saw should be even, and the saw edge should be cut After all, do not twist or break to avoid deformation of the pipe mouth section.
2. Threading: Thread the broken pipes in batches according to the diameter of the pipe. Generally, threading is done twice for pipes with a diameter of 15-32mm, three times for pipes with a diameter of 40-50mm, and three times for pipes with a diameter of 70mm or above. -4 times is appropriate.
a. Use a threading machine to thread, clamp the pipe on the threading machine chuck, leave an appropriate length to clamp the chuck, align the plate cover number, install the die, and align the appropriate position of the scale according to the pipe diameter. Hold the fixed trigger tightly, align the lubricant tube with the thread head, turn on the machine and push the plate, wait until the thread thread reaches the appropriate length, and then gently release the trigger.
b. Use the manual threading plate to thread, first loosen the fixed trigger, return the threading plate plate to zero, install the die according to the sequence number, align the plate with the required scale, tighten the fixed trigger, and place the pipe on In the pressure clamp, leave an appropriate length for clamping. Gently insert the thread plate into the pipe to make it moderately tight. Then push the thread plate with both hands, put on 2-3 buckles, and then stand to the side to pull the thread plate. , the force should be even. When the thread is about to be set, gently release the trigger, turn on the machine and withdraw the plate, maintaining the taper of the thread.
3. Assemble pipe fittings: According to the on-site surveying and mapping sketch, assemble the pipe fittings that have been threaded.
a. When assembling pipe fittings, the required pipe fittings should be brought into the pipe thread buckle, and the tightness should be tested (generally, it is appropriate to bring in 3 buckles by hand), apply lead oil on the thread buckle, wrap it with hemp, then bring it into the pipe fitting, and then use Use a pipe wrench to tighten the pipe fittings so that 2-3 buckles are exposed from the thread. Remove the hemp head, wipe off the lead oil, and put the number in the appropriate position and wait for straightening.
b. Select the appropriate pipe wrench according to the diameter of the pipe to which the pipe fittings are to be installed.
4. Pipe section straightening: Straighten the pipe section with installed pipe fittings before installation.
a. Apply lead oil to the threaded joints of the pipe sections where the pipe fittings are installed, and connect two or more sections. When connecting, do not just pay attention to the direction of the reserved opening but the curvature of the pipe. After aligning each other, turn the direction of the reserved opening. Get to the right place and stay decent.
b. After the pipe sections are connected, it is necessary to check whether the pipe diameter, reserved opening direction, and diameter reduction position are correct according to the planning drawings before straightening.
c. The straightening of the pipe section should be placed on the pipe adjusting rack or the pipe adjusting platform. Generally, it is suitable for two people to operate. One person visually inspects the end of the pipe section, and the other person hits the bend with a hammer, while hitting and observing, until Make sure there are no twists in the straightened pipe section, and mark the connection point between the two pipe sections. Remove one or more sections, and then connect another section or sections until the adjustment is completed.
d. For pipes with excessive twists or large diameters at the connection points of pipe sections, ovens or gas welding can be used to heat them to 600-800°C (fire red). Place the pipes on a pipe rack and roll them continuously, using the weight of the pipes to make them Straighten it, or use a wooden pad to straighten it by tapping it with a hammer on the heated place. After straightening, roll it continuously before cooling. When the temperature reaches the right time, apply engine oil on the heated place. All screws that are straightened by heating must be marked, removed, re-coated with lead oil and wrapped with hemp, and then the pipe section is aligned with the mark and tightened.
e. When straightening the pipe section with the valve installed, the valve cover should be removed first, and the valve should be firmly padded before hitting to prevent the valve body from cracking.
f. Galvanized carbon steel pipes are not allowed to be straightened by heating.
g. Do not damage the pipe section when straightening it.
Post time: Oct-24-2023