Development of technology and equipment for assembly and welding of one-way hydraulic cylinder

Contents

CONTENTS

INTRODUCTION

1 ANALYSIS OF THE STATE OF THE QUESTION

1.1 Product characteristics and operating conditions

1.2 Article material and its weldability

1.3 Selection of welding method

1.4 Selection of work direction

2 PROCESS SECTION

2.1 Selection of welding materials

2.2 Calculation of parameters of arc welding mode in protective gas by melting electrode

2.3 Hydraulic cylinder assembly and welding process

2.4 Quality Control

3 DESIGN SECTION

3.1 Power Supply Selection

3.2 Description of main welding equipment

3.3 Installation for welding of sleeve ring seams

3.4 Stand for mechanized assembly of hydraulic cylinder

CONCLUSION

LIST OF SOURCES USED

Introduction

Currently, hydraulic cylinders are used as actuators used in various machines and have been widely used in various branches of mechanical engineering.

Enterprises - manufacturers of hydraulic cylinders, use high-quality, processed internal surface finished pipes produced at specialized enterprises. The rods are also supplied by highly specialized companies producing only metal rod finishing and chromium plating. As a result, in all stages of production, a narrow specialization, studying the process to the smallest intricacies, the possibility of using high-performance specialized equipment in production, and minimizing the influence of the human factor.

At the same time, its individual parts - the body of the hydraulic cylinder with end elements, etc., must be connected by welding.

The purpose of this graduation qualification work, based on the analysis of the status of the issue, is to develop the process of assembling and welding a hydraulic cylinder, select standard main welding and auxiliary equipment and design technological equipment for assembling and welding single-acting hydraulic cylinders.

Select Work Direction

Studying the issue of the operating conditions of the article, the material and its weldability, as well as a possible welding method, it can be concluded that the development of welding technology in the environment of protective gases with a melting electrode, when manufacturing the body of a hydraulic cylinder made of structural low-alloy steel, it is possible to increase the productivity and quality of the article.

Therefore, the purpose of the work in the production of hydraulic cylinders is to carry out the following measures:

- selection of basic welding materials that will facilitate the performance of quality welding joints;

- development of process of assembly and welding of one-way hydraulic cylinder housing;

- selection of standard main welding and auxiliary equipment for assembly and welding of hydraulic cylinders;

- development of technological tooling to improve the process of assembly of elements of the article for welding.

2.3 Hydraulic cylinder assembly and welding process

1 Procurement operation

Cutting of pipes and chrome rods into blanks is performed on belt-cutting machines. These machines provide low cutting forces and, as a result, low clamping force, which is necessary to prevent deformation during clamping [23].

1. Perform incoming inspection of parts.

- honed pipes shall be marked in accordance with GOST 956775;

- depending on the pipe diameter, the surface purity shall be 0.20.4 μm;

- pipe ends shall be closed with plastic plugs.

2. Cut the pipes and chrome rods on the strip cutting machine.

3. Prepare the edges of the pipe for welding on the side of the rear cover and the opposite end.

4 Edge preparation shall comply with GOST 1477176, connection type C11.

5. If necessary, it is possible to drill the inner diameter of the sleeve to the welding zone by increasing the seating diameter for the through bushing by 1.0-2.0 mm.

6. Perform inspection of welding materials in accordance with RD 34.10.12594.

Assembly and Tack Operation

1. Attach the rear cover of the housing on the rotator, and the front cover on the rear pneumatic head on a specialized installation.

2. Make sure that the pipe cavity is clean from dirt, undercuts, dents, bottoms and other defects.

3. Perform the assembly of the hydraulic cylinder housing, respecting the tolerances of alignment of the covers (trunnions, flanges) with respect to the pipe axis in accordance with Specification 41430015683107806 or GOST 1741191.

- fit of trunnion or flange on H9/h10 sleeve.

4. Then attach both covers to the sleeve:

- number of tacks on each side, pcs. 4;

- length of tacks 20-30 mm.

Welding equipment:

- inverter power supply Phoenix 551 Pr. Puls;

- Phoenix Progress Drive 4L WE feed mechanism;

- EWM MT550WR 3M burner.

Auxiliary equipment:

- JODE Automatic Assembly and Welding Installation

Welding Materials:

- additive material EWM SW 70S G3 1.2 mm;

- protective gas mixture 80% Ar + 20%, EN 4391995.

Tack mode parameters:

- welding current, 238 A;

- arc voltage, 19 V;

- wire feed speed, 2.6 m/min;

- welding speed, 0.14 m/min;

- protective gas flow rate, 12 l/min.

3 Welding operation

1. Weld the rear covers to the honing pipe in accordance with the weld parameters in accordance with GOST 1477176.

Main welding equipment:

- inverter power supply Phoenix 551 Pr. Puls;

- Phoenix Progress Drive 4L WE feed mechanism;

- EWM MT550WR 4M burner.

Auxiliary equipment:

- JODE Automatic Welding Unit

Welding Materials:

- additive material EWM SW 70S G3 1.2 mm;

- protective gas mixture 80% Ar + 20%, EN 4391995.

Welding mode parameters:

- welding current, 346 A;

- arc voltage, 22.4 V;

- wire feed speed, 5.26 m/h;

- welding speed, 0.19 m/h;

- protective gas flow rate, 12 l/min.

4 Assembly and Tack Operation

1. The bonnet (connector) must be placed on the rear cover, since welding of the bonnet to the sleeve can cause distortion of the internal diameter of the pipe.

2. If the design of the hydraulic cylinder, of course, requires welding of the box to the sleeve, it must be located as close as possible to the rear cover.

Welding equipment:

- inverter power supply Phoenix 551 Pr. Puls;

- Phoenix Progress Drive 4L WE feed mechanism;

- EWM MT550WR 3M burner;

Auxiliary equipment:

- JODE Automatic Welding Unit

Welding Materials:

- additive material EWM SW 70S G3 1.2 mm;

- protective gas mixture 80% Ar + 20%, EN 4391995.

Welding mode parameters:

- welding current, 346 A;

- arc voltage, 22.4 V;

- wire feed speed, 316.3 m/h;

- welding speed, 11.56 m/h;

- protective gas flow rate, 12 l/min.

5 Welding operation

1. Weld the connectors to the base of the covers (if necessary to the sleeve), pipe.

2. Observe perpendicular tolerance with respect to pipe axis in accordance with specification 41430015683107806 or GOST 1741191.

3. Drill holes in the sleeves after welding of connectors with grinding of burrs on the sleeve mirror with spherical cutter.

Welding equipment:

- inverter power supply Phoenix 551 Pr. Puls;

- Phoenix Progress Drive 4L WE feed mechanism;

- EWM MT550WR 4M burner;

Auxiliary equipment:

- JODE automatic welding unit;

- drilling mill on the magnetic rack of the Metallo MAG 32.

Welding Materials:

- additive material EWM SW 70S G3 1.2 mm;

- protective gas mixture 80% Ar + 20%, EN 4391995.

Welding mode parameters:

- welding current, 338 A;

- arc voltage, 22.7 V;

- wire feed speed, 5.13 m/h;

- welding speed, 0.21 m/h;

- protective gas flow rate, 12 l/min.

6 Assembly and Tack Operation

1. Attach the rod to the cartridge, pre-process the clamping place.

2. Clamp must be made through split bushing or in cams boring strictly along rod diameter with overlap of not less than 70% of rod area on cam length.

2. Observe alignment tolerance in accordance with Specification 41430015683107806 or GOST 1741191.

3. Attach the eye to the rod using semi-automatic welding.

- after tacks grind metal from slag and splash

Welding equipment:

- inverter power supply Phoenix 551 Pr. Puls;

- Phoenix Progress Drive 4L WE feed mechanism;

- EWM MT550WR 4M burner;

Auxiliary equipment:

- JODE automatic welding unit;

Welding Materials:

- additive material EWM SW 70S G3 1.2 mm;

- protective gas mixture 80% Ar + 20%, EN 4391995.

Welding mode parameters:

- welding current, 328 A;

- arc voltage, 22.7 V;

- wire feed speed, 5.13 m/h;

- welding speed, 0.21 m/h;

- protective gas flow rate, 12 l/min.

7 Welding operation

1. Weld the eye to the rod, observe the weld parameters in accordance with GOST 1603780.

2. When welding the eye to the rod, it is necessary to protect the chrome surface in the near-seam zone from welding splashes.

3. After each pass, clean the surface of the seam with a metal brush.

Welding equipment:

- inverter power supply Phoenix 551 Pr. Puls;

- Phoenix Progress Drive 4L WE feed mechanism;

- EWM MT550WR 4M burner;

Auxiliary equipment:

- JODE automatic welding unit;

Welding Materials:

- additive material EWM SW 70S G3 ∅1,2 mm;

- protective gas mixture 80% Ar + 20%, EN 4391995.

Welding mode parameters:

- welding current, 348 A;

- arc voltage, 22.4 V;

- wire feed speed, 5.19 m/h;

- welding speed, 0.23 m/h;

- protective gas flow rate, 12 l/min.

8 Welding Inspection Operation

1. Perform visual inspection of the welded structure.

- surges, burns, non-brewed craters, non-fusing of edges, external cracks of seam, and near-seam zone, splashes, non-fusing of seam root are not allowed;

- defective sections of joints shall be removed, brewed and checked again. Removal of joints - according to the manufacturer's technology;

- weld defects to be corrected shall be removed to the base metal and brewed again in the same manner and using the same welding materials as the weld;

- welds shall be cleaned of slag and splash. In terms of appearance, the weld shall have a smooth transition to the base metal, a uniform fine-skinned surface, the same along the entire length of the weld [23].

2. Quality control of welded joints shall be carried out as per GOST 3242 by external inspection and measurements.

Conclusion

Thus, during the completion of the graduation qualification bachelor's work, an analysis was made of the state of the issue of manufacturing the product - hydraulic cylinder, based on the operating conditions, material and its weldability, as well as the choice of the welding method.

As a result of the analysis, the technological process of manufacturing a hydraulic cylinder using a method of welding in the environment of protective gases with a melting electrode was developed, welding materials were selected that contribute to improving the quality of welded joints .

Presented technology and selected complex of welding and auxiliary equipment for assembly and welding of hydraulic cylinders allows to significantly reduce labour intensity of their manufacture, to increase quality and reliability of the product.