What should be paid attention to during pipeline pre installation II
Welding of pipes and fittings
(1) Argon tungsten arc welding or argon arc welding backfill welding. When the pressure exceeds 21mpa, argon 5L /min should be passed inside the tube at the same time;
(2) When the wall thickness of the pipe is greater than 2mm, the outer circle should be cut into a 35° groove, and leave a 3mm gap at the mouth; When the pipe wall thickness is less than or equal to 2mm, the groove is not cut, and a 2mm gap is left at the mouth.
(3) The pipe axes must coincide, the amount of misalignment is less than 15% of the wall thickness, and the partial slope is less than 1:200;
Installation of pipe clamp
(1) the plate of the pipe clamp is generally welded in the structure directly or through the bracket such as Angle steel, and the bracket is fixed with expansion bolts on the concrete floor surface or wall side;
(2) pay attention to leveling when installing the pipe clamp, that is, the mounting surface is at the same height;
(3) the spacing of the pipe clamp: when the pipe diameter is ≤φ10, about 0.5~1 meters; Pipe diameter φ10~25 about 1~1.5 meters; Pipe diameter φ25~50 about 1.5~2 meters, but in the right Angle turning, both sides should be each with a pipe clamp.
(1) Connect the pipe joint with the equipment, pipe and pipe fittings section by section until complete preinstallation;
(2) See Chapter 4 for the installation method of pipe fittings;
(3) At the same time, the pipe clamp plate shall be welded on the structure or bracket, and the pipe shall not be welded on the pipe clamp or bracket;
(4) After the pre-installation is completed and the inspection is qualified, print a matching mark for the pipeline, a number for each piece, and list it into a table for future use. After the pipes are removed and cleaned, restore them according to the serial number.
(1) Before installation, all steel pipes can be pickled according to the requirements of Chapter 6. In particular, the steel pipes connected with the clip-sleeve pipe fittings should be pickled first, and then the clip-sleeve should be fastened to the pipe end in advance;
(2) All pipe fittings should be cleaned with kerosene before installation, and the O-ring inside should be temporarily taken out and kept until formal installation.
(3) During the construction, the oil port, pipe fittings, pipe end and other openings of the pump, distributor and other equipment should be kept clean, and water, dust and other foreign bodies should not be allowed to enter;
(4) The pipeline should be laid in a free state, and the welded pipeline should not be fixed and connected by excessive radial force;
(5) The oil hole of the bearing seat should be checked in advance to check whether the internal oil circuit is smooth and whether the thread of the oil port matches the fittings.