RU2548336C2 - Production of large-sized flat structure - Google Patents

Abstract

FIELD: process engineering.

SUBSTANCE: end surface of fragments to be coupled are levelled and cleaned. Bores are drilled therein and thread is cut. Said fragments are degreased by gasoline. Then, fragments are assembled to flat structure with the help of studs made of stainless steel. Then, edges are finished for welding, fragments are degreased and subjected to arc welding with application of bronze wire in lines of joint of said fragments. Now, welds are finished and surface of made structure is subjected to sand blasting.

EFFECT: higher strength and reliability of welds.

1 ex, 1 dwg

Description

The invention can be used for the manufacture of large-sized structures made of brass, for example, in mechanical engineering.

The invention relates to a technology for producing high-strength connection of fragments that make up the general structure obtained by a combined method using mechanical fastening and welding.

Welding of brass structures is known, for example, from the copyright certificate SU 1146159 A (B23K 9/16, published 03/23/1985). This copyright certificate discloses a method for pulsed-arc welding of 1 mm thick brass, which is performed end-to-end with a non-consumable tungsten electrode in an argon atmosphere. This method provides welded joints equal in strength to the base metal. However, this method is used for welding thin-sheet brass and is not intended for welding large-sized thick-layer products.

From the copyright certificate SU 1816615 A1 (B23K 37/04, published 05/23/1993), for example, argon arc welding using tie rods installed in the openings of the parts to be welded is known. However, this copyright certificate does not disclose the possibility of welding large-sized thick-layer products made of their brass.

The objective of the invention is the improvement of the technological process for producing a welded joint, which includes, along with welding, the fastening of the welded fragments of the structure using studs.

The technical result achieved by the implementation of the invention is to increase the strength and reliability of the welded joint of the structure by creating strong bonds between fragments of the structure, and the resulting welded structure is operable under conditions of not only static but also cyclic loading.

A method of manufacturing a large-sized flat design from fragments obtained by casting from brass, in accordance with the invention, includes leveling and cleaning the end surfaces of the fragments to be joined, drilling holes in them and cutting threads, degreasing fragments with gasoline, assembling fragments into a flat design using studs made stainless steel, cutting edges for welding, degreasing fragments and conducting argon-arc welding using bronze wire containing 0.5-0.7 wt.% Zirconium, along the lines of connection of fragments, stripping of welds and sandblasting the surface of the resulting structure.

The placement of the studs on the ends to be welded allows for the power fastening of the fragments between themselves and a uniform gap for welding between them. The introduction of steel studs at the stage prior to welding, allows to increase the strength of the welded joint. Creating strong bonds between fragments using mechanical fastening and welding can improve the reliability of the structure.

The method is as follows. Seven fragments of a brass bas-relief are made of brass using casting. After that, the fragments are cleaned, deburred and the end surfaces are leveled. Then the fragments are blown with air and degreased with gasoline.

Pure fragments are mounted on the shelf, fitting them tightly together. Next, marking is performed for drilling and cutting in the holes of the thread, after which the holes are drilled and the threads are cut. Having completed these operations, the fragments are assembled using studs made of stainless steel. After this, the edges are cut for welding, followed by air purging and degreasing. Cutting was performed on both sides of each fragment. The marking and installation of the studs ensured alignment of the fragments and their flatness among themselves.

The drawing shows a diagram of the indicated markup and a general view of a brass bas-relief composed of fragments. Elements 1-7 indicate fragments of brass. The length of the entire structure is 1.8 m, the width is 1.4 m, and the fragment thickness is about 25 mm.

The collected fragments are then welded at the points of cutting by argon arc welding using an additive - bronze wire containing 0.5-0.7 wt.% Zirconium. After welding according to the grooves, on one or the other side of the plane, the irregularities in the welding spots are cleaned using a drill. Then, to create an even surface of the bas-relief, sandblasting of the entire structure is carried out. This operation allows you to achieve a smooth glossy surface of the brass bas-relief.

The following is an example implementation of the method.

Example. Bas-relief of the academician of the USSR Academy of Sciences A.N. Tupolev was made from seven fragments obtained by casting from brass. After manufacturing, the end surfaces of the fragments were smoothed out by removing burrs and leveling the end surfaces. Then it was purged with air, degreased and again purged with air. Pure fragments were mounted on the rack, fitting them tightly together. They made markings for drilling holes and threading them. Drilling holes was carried out on a drilling machine, and thread cutting was performed by a tap manually. Next, the fragments were purged with air and degreased with gasoline. Then the fragments were assembled with the installation of M10 studs made of stainless steel.

After assembling the fragments, the edges were cut along their ends, followed by air purging and degreasing. Cutting was carried out from two sides (planes).

Next, argon-arc welding was carried out in the places of cutting. A wire with a diameter of 3 mm was used as an additive. The wire material is bronze (copper with the addition of 0.5-0.7 wt.% Zirconium). Then, irregularities were cleaned from the surface in the places of welding using mechanical treatment with a drill. Next, the fabricated structure was sandblasted to create a smooth surface of the bas-relief, after which it was blown with high pressure air. This provided the surface of the bas-relief with an even glossy look.

Claims (1)

A method of manufacturing a large-sized flat design from fragments obtained by casting from brass, including aligning and cleaning the end surfaces of the fragments to be joined, drilling holes and threading in them, degreasing fragments with gasoline, assembling the fragments into a flat design using studs made of stainless steel, cutting edges for welding, degreasing fragments and conducting argon-arc welding using bronze wire containing 0.5-0.7 wt.% zirconium along the lines connecting fragments, stripping welds and sandblasting the surface of the fabricated structure.