CN1318707A - Pipeline welding method - Google Patents

Abstract

A welding method for pipe with flange is to expand the hubbed flange inside diameter of 0.3-0.4 mm by prefabricating from high diameter end with the reservation of 10-15 mm in the other end to form a boss in the flange, to insert the pipe into the hubbed flange with the pipe end sustaining to the boss, aligning and spot welding, keep welding after calibration. The said method for pipe to pipe is to prefabricate the adjacent pipe ends of to be a convex and concave faces to form a position and negative mouth, to butt-joint and insert them together for spot welding and keep welding after calibration and alignment.

Description

Pipeline welding method

The present invention relates to a kind of pipeline welding method, be applicable to the pipeline welding of the ball pipeline purging of adopting the accurate pipe making of heavy wall, the ball pipeline purging is mainly used in the pipeline cleaning of the product oil of lubricant oil, prevents the pollution between the oil product.

The installation requirement of ball pipeline purging mainly shows the control to installation precision, existing pipeline welding method is only simply processed bevel for welding, directly butt welding then, because can not burn-through, weld strength is not enough, and between the pipe after welding polishing welding seams add sleeve pipe again and fix, so the processing method complexity, the aligning difficulty is big, and quality is difficult for guaranteeing, card ball phenomenon takes place in inefficiency easily when pipeline cleans.

Purpose of the present invention is the shortcoming and deficiency in order to overcome above-mentioned prior art just, and a kind of easy construction is provided, and butt joint is easy, the pipeline welding method that quality of processing is good, thus can increase work efficiency, use manpower and material resources sparingly.

The objective of the invention is to realize by following technical proposal:

Pipeline welding method comprises the welding of pipe and flange and the welding between the pipe, it is characterized in that:

A) welding of pipe and flange: the internal diameter with hubbed flange enlarges from high diameter end processing earlier, size increases to greater than external diameter of pipe 0.3-0.4mm, end stays 10-15mm length in addition, make and form an inner convex platform in the flange, then pipe is inserted hubbed flange, pipe end and jail, boss top, the back continuous welding is proofreaied and correct in alignment back spot welding;

B) welding between pipe and the pipe: earlier two adjacent pipe ends are processed into protruding, concave surface mother-son mouth, after again the convex-concave mother-son mouth butt joint of two pipe ends being inserted firmly, in two pipe joint spot welding, continuous welding again after the straightening.

Owing to take technique scheme, make the technology of the present invention compared with the prior art have following advantage and effect:

A) this method essential factor that will influence ball pipeline purging installation precision is transferred to easy control and course of working from unmanageable welding process, makes welding method more easy;

B) this method can be saved the groove welding of butt joint pipe end, has improved weld strength, and butt joint easily, and is easy to operate, and step is simplified;

C) the pipe inside weld is no longer polished, and also need not add sleeve pipe and fix, and has promptly saved material, also increases work efficiency;

D) machining accuracy height, the joint is smooth in the pipe, and stifled ball phenomenon can not take place.

Description of drawings:

Fig. 1 pipe and flange welding schematic representation;

The convex-concave platform schematic representation of Fig. 2 pipe butt joint pipe end;

Welding schematic representation between Fig. 3 pipe.

Embodiment further specifies the technology of the present invention below in conjunction with accompanying drawing:

Fig. 1 is the welding schematic representation of pipe and flange, during welding, the internal diameter with hubbed flange (1) enlarges from the processing of hub end earlier, and size increases to greater than pipe (2) external diameter 0.3-0.4mm, end leaves 10-15mm length (10) in addition, in flange, form a boss (3), then pipe is inserted hubbed flange, pipe end and jail, boss top, alignment back spot welding, with pipe and flange outer wall butt welding in spot, the welding of flange and pipe is promptly finished in continuous welding again (4) after the alignment again.

Fig. 2 is protruding, the concave station schematic representation of pipe butt joint pipe end, Fig. 3 is the welding schematic representation between the pipe, during welding, two adjacent pipe (7), (8) pipe ends are processed into male and female face mother-son mouth (5), (6), after again the butt joint of male and female face mother-son mouth being inserted firmly, in joint spot welding, the welding between the pipe is promptly finished in continuous welding again (9) after the straightening.

Use welding method of the present invention, the DN80-100 pipe of the ball pipeline purging of introducing from the U.S. is constructed, its precision can reach ± 0.2mm, surpass U.S.'s installation requirement ± the 0.3mm precision, installation period, operation so far was normal, and pipe ball phenomenon did not take place than having saved 15% in the original plan.

Claims (1)

1, pipeline welding method comprises the welding of pipe and flange and the welding between the pipe, it is characterized in that:

A) welding of pipe and flange: the internal diameter with hubbed flange enlarges from high diameter end processing earlier, size increases to greater than external diameter of pipe 0.3-0.4mm, end stays 10-15mm length in addition, make and form an inner convex platform in the flange, then pipe is inserted hubbed flange, pipe end and jail, boss top, the back continuous welding is proofreaied and correct in alignment back spot welding;

B) welding between pipe and the pipe: earlier two adjacent pipe ends are processed into protruding, concave surface mother-son mouth, after again the convex-concave mother-son mouth butt joint of two pipe ends being inserted firmly, in two pipe joint spot welding, continuous welding again after the straightening.