SU1687406A1 - Method for manufacturing parts - Google Patents

Abstract

The invention relates to welding, is used in the manufacture of shear rams of preventers by surfacing and can be used in the oil and gas industry. The purpose of the invention is to increase the reliability of parts. This goal is achieved by the fact that surfacing of scarves with a copper material is carried out in several layers with the intermediate layer being made by alternating rollers welded with high-level electrodes and a high-hard electrode. The first layer is made of highly hard material with a thickness equal to the critical thickness at which no cracks have yet formed. 1 il.

Description

The invention relates to welding, is used in the manufacture of shear preventer dies, intended for sealing the mouth during surface and offshore drilling in order to prevent accidents and to preserve wells.

The aim of the invention is to improve the reliability of parts.

The drawing shows the implementation of the method.

Surfacing of two layers 2 of highly hard material and an intermediate layer onto the die body I is carried out. The intermediate layer is made by alternating rollers of high-plastic 3 and high-hard 4 material.

The overlaying of the die with a highly hard material is carried out in several layers, with the intermediate layer being made by alternating rollers welded with highly plastic and highly hard electrodes. The intermediate layer is made of highly plastic (austenitic) material, is located between the areas of maximum permissible thickness of the high-hardened layer and acts as a damping layer, reducing welding stresses due to the high ductility of the metal, which prevents the formation of cracks

The presence of an intermediate layer with high ductility, but lower strength, can lead to plastic deformations of the cutting edge of the die under critical loads. Therefore, the intermediate layer is made, a series of rollers of an eustenitic, highly plastic and highly hard material.

PRI me R. On the body of the die (dimensions 40x200 mm) (steel 25HGSDYUCHL) produced multilayer overlaying by manual arc welding with EN-60 electrodes (Sv-70KhZMN). The cladding was carried out with preliminary concomitant heating of 300–400 ° C, electrodes with a diameter of 4 mm at a current of 140 A. After surfacing layer 2 to a thickness of 8–10 mm (which corresponds to the critical thickness of the weld

AND

/ -

O CO ± O O

high-hard layer) produced by welding one intermediate layer, a series of rollers: one pass - electrode AE 981/15 (Sv-09H 16M25W6A p). another pass

-electrode "d. After surfacing of the intermediate layer, the operation of surfacing a high-hard layer with a thickness of 8 was repeated.

-10 mm. The total thickness of the deposited layer was 22 mm, which is 2.2 times greater than the allowable thickness of the surfacing using the prototype method. X-ray inspection and macro-structural analysis of the weld metal of the cutting edge confirmed the absence of cracks.

If necessary, the repetition of the deposition of high-hard and intermediate layers, it is possible to obtain significantly greater thickness of the weld metal of the cutting edge. The use of the proposed method allows to increase the reliability of the shear die for

by increasing the thickness of the solid layer dam when the tubes are cut off with the largest single meter.

Claims (1)

The invention The method of manufacturing parts is predominantly a shear preventer die with a weld-over cutting edge, in which multi-layer surfacing is carried out from materials with different mechanical characteristics with the implementation of at least one layer in the form of alternating rollers and different mechanical characteristics, characterized in that In order to increase reliability, the first layer is made of a high-hard material with a thickness corresponding to the critical thickness, in which cracks occur, and the layer and The alternating rollers are made of hard and highly ductile materials, and then the remaining layers are made of highly hard material.