Insulation spiral steel pipe joints play an important role in construction acceptance, so the joints must be operated according to standards and specifications: sure that the spiral steel pipe welded joints have passed X-ray inspection and are qualified, and clear the sundries of the welded joints and the joint leather case. Measure the length of the repaired mouth. The length is generally less than or equal to 50CM. Wrap the holster around the repaired mouth for a week to make the length of the overlap between the two ends average.

Use a heat shrinkable tape with a width of 150mm to wrap the lap for one week. Use a small fire to bake the two layers of heat shrinkable tape in turn until the adhesive layer is micronized and fixed by lap, and then press the baked layer. The cover is centered on the lap seam, and then use a medium heat to bake the gland back and forth until the gland and the heat shrinkable tape are completely bonded without warpage and air bubbles. During the heating process, the gland can be smoothed with gloves or rollers Heat shrinkable tape is tightly bonded.

After the gland is pressed, start from the middle of the heat shrinkable tape, first bake the side that overlaps the sleeve, and start from the bottom when baking, and follow the baking rules from bottom to top, from inside to outside to prevent air bubbles Generate; adjust the flame length of the spray gun, first average heat along the center of the heat shrinkable belt, and then heat the two ends in turn after the middle shrinkage. During the heating process, the gun should be moved back and forth to ensure that the heat shrinkable belt is not partially overheated. When heating and shrinking, you should carefully check whether there is hot melt adhesive overflowing the edge of the heat shrinkable band.

After the shrinkage is finished, check again whether the heat shrinkable tape and the gland have warpage and air bubbles. If there is any, the air bubbles should be repaired and removed in time to ensure that the heat shrinkable tape and the gland are flat. After confirming that the heat shrinkable tape is sealed, mix the black and white material in a container according to 1:1, pour it into the heat preservation mouth quickly, and then seal the mouth.