ПРИМЕНЕНИЕ ЛАЗЕРНОЙ СВАРКИ ПРИ ИЗГОТОВЛЕНИИ НЕФТЕГАЗОВОГО ОБОРУДОВАНИЯ

Abstract

In the process of making oil and gas weld-fabricated equipment usually use different types of arc welding. Quite often the decrease in strength properties of weld-fabricated connection is the result of thermal effect of welding arc and phase transformations in a molten weld pool and heat affected zone. Arising field of residual welding stresses reduces technological strength, creates undesirable deformations and predetermine the need of using heat treatment operations. Today the widespread use of laser welding in assembly of the oil refining and oil and gas equipment is impossible because of many process specifics. However, there are some parts of equipment, where the laser welding has the advantage over other methods. This article contains results of comparative researches of weld-fabricated connection, produced by laser and arc welding for rationale possibility of using laser welding in the technological manufacturing process of the weld knot of tubes to tube grate in heat exchangers which are made of 15H5М steel. Article also includes qualitative and quantitative analysis of the microstructure and chemical composition of the weld knots. Results of the research proved that in case of local heat inputs, reducing the size of the weld and heat affected zones, laser welding can significantly minimize the influence of welding stresses on the geometric parameters of the tube grate and avoid the cold cracking. Also presented the results of comparative research of parameters of corrosion relief of surface (CRS) sample welds produced by arc and laser welding, which helps us in the question of increasing corrosion resistance.