Welding Machine


October 23, 2017 Facebook Twitter LinkedIn Google+ Uncategorized



Welding is the welding power to provide certain characteristics of the electrical appliances, welding simple and convenient because of the simple and reliable, even after welding with the same strength of the advantages of metal materials are widely used in various industrial fields, such as aerospace, ships, automobiles, containers and so on.

Table of content

1. Introduction

2. working principle

3. Classification

4. Product Categories

5. Auxiliary equipment

5.1 Energy efficient

5.2 stable performance

5.3 centralized control

6. Advantages and disadvantages

6.1 Advantages

6.2 Disadvantages

7. Introduction to cold welding

7.1 Introduction

7.2 Features

8. Welding operation specification

8.1 Connection check

8.2 Leakage

8.3 work is suspended

8.4 mobile welding machine

8.5 Not used equipment

8.6 Maintenance

9. Frequently Asked Questions

10.Other references

11.List of welding machine manufacturers

1. Introduction

The welding machine is actually a transformer with a drop in the external characteristics, 220V and 380V AC current into a low-voltage direct current, welding machine generally according to the output power type can be divided into two kinds, one is the AC power supply; one is DC. DC welding machine can be said to be a high-power rectifier, positive and negative, AC input, the transformer after the transformer, and then rectifier rectifier, and then output with a low power characteristics of the output, the output is turned on and off Will produce a huge voltage change, the two poles in the moment when the short-circuit ignited the arc, the use of arc to generate welding electrodes and welding consumables, cooling and then to achieve the purpose of their combination. Welding transformer has its own characteristics, the external characteristics of the electrode is ignited after the sharp decline in the characteristics of the voltage.

2. working principle

The main part of the welding machine is a step-down transformer, the secondary coil is welded at both ends of the workpiece and the electrode, the work of igniting the arc, the arc in the high temperature welding electrode welded to the gap in the workpiece. As the welding transformer core has its own characteristics, it has a sharp drop in the characteristics of the voltage, that is, after the electrode ignition voltage drop; in the electrode was shortened bonding, the voltage is a sharp decline.

In the welding operation, although the current in the circuit is equal, but because of the resistance is not the same, in the fixed contact at the maximum resistance (the resistance called contact resistance), according to the thermal law of the law (also called Giorg’s Law) , That is, Q = IR. t can be seen: the current is equal, the greater the resistance of the higher parts of the heat, so the welding, the electrode contact is connected to the metal contact at the contact resistance of the largest, then the heat generated in this part of the natural Also the most, plus the electrode is the lower melting point of the alloy, naturally easy to melt. After the melting of the alloy welding rod bonded to the object to be welded, after cooling the bonding object will be bonded in one.

General DC inverter welding machine panels are equipped with output DC current adjustment knob. Inverter DC welding machine first single-phase AC 220V voltage or three-phase AC 380v voltage bridge rectifier, filter, and then supply power switching devices for inverter processing.

A small part of the inverter welding machine first use 555 time base circuit and other pulse generation circuit to generate rectangular pulse wave, and then use the transistor current amplification, and then with a pair of complementary FET to amplify the voltage, resulting in high-frequency signal, and finally the use of boost The transformer is boosted and the induced alternating current is obtained on the secondary winding. The size of its power depends on the magnification of the amplifier circuit.

Inverter welding machine used by the IGBT tube composed of single-ended forward inverter circuit, the control system using pulse width modulation chip SG3525, the inverter frequency of 20kHz, and can be constant current external control. System at no load, due to the use of voltage feedback control, PWM modulator intermittent output pulse, due to the low frequency of intermittent oscillation and pulse width is narrow, so not only no load loss is small, and the transformer is not easy to saturation. As the type of welding machine with pulse width modulation PWM as the core of the control technology, which can get better constant current characteristics and excellent welding process effect.

3. Classification

There is no authoritative classification of the classification of welding machines, the following classification is mainly based on the industry to use a simple classification:

1) The main use of welding and welding enterprises are: AC arc welding machine, DC welding machine, welding machine, carbon dioxide protection welding machine, butt welding machine, spot welding machine, submerged arc welding machine, high frequency welding machine, flash Welding machine, welding machine, welder welder welding machine and DC welding machine

(2) There are two types of DC welding: AC motor is based on the installation of the original rectifier, there is a DC generator. DC welding machine mainly welded nonferrous metals, pig iron mainly. AC welding machine mainly welded steel plate.

(3) argon arc welding machine, carbon dioxide protection welding machine, high frequency every welder, flash butt welding machine. Argon arc welding machine, carbon dioxide welding machine can be mainly welded 2MM below the sheet and non-ferrous gold layer. Flash butt welding machine mainly docking copper and aluminum joints and other objects, high frequency every welder main pipe factory welded steel pipe.

(4) submerged arc welding of the main welded steel structure, the bridge H steel, the word round bar and other thick steel structure materials.

(5) gas shielded welding: argon arc welding, carbon dioxide welding, welding under the protection of the gas will not be oxidized, welding welding firm, welding non-ferrous metals, thin material can be welded.

(6) laser welding machine: the inside of the solderable transistor lead.

(7) butt welding machine: cable chain factory mainly welded anchor and other objects. Can be connected to the steel and so on.

(8) multi-function welding machine

(9) spot welding machine

(10) butt welding machine

(11) bolt welder

(12) carbon dioxide ammonia gas welding machine

4. Product Categories

Commonly used welding machine from the welding current points are divided into DC, AC, pulse three categories, but commonly used in AC and DC inverter welding machine. AC welding machine is a special transformer, but the DC inverter welding machine to be more complex, and its control is now basically the use of frequency

1, aluminum parts defect repair machine

2, mold repair machine

3, EDM surfers

4, high-energy micro-arc cold welding machine

5, cold welding repair machine

5. Auxiliary equipment

The welder aids include gas shields that prevent the operator from being exposed to arcs or other welding energy generated by ultraviolet rays, infrared rays or other rays that hurt the eyes. Welders eye, face and neck masks, white work clothes, welders and protectors Feet and so on.

5.1 Energy efficient

The energy saving of the welding machine is reflected in the energy saving of the no load and the energy saving in the load. No load when the main circuit, the fan, etc. all into the stop state, no-load power consumption only a few watts; welding machine load efficiency than the thyristor rectifier to high. According to the relevant statistics, the 2008 national welding industry, the demand for DC welding machine is 89 million units, if all the use of welding machine, can directly save 43,000 tons of copper, steel 64,000 tons, saving 680 million KW.H, indirect Saving 566,500 tons of coal, water 10.34 million tons, reducing CO2 emissions of 1,144,500 tons. It can be seen, vigorously promote the welding machine has great economic and social benefits.

5.2 stable performance

As the welding machine operating frequency of 20KHZ above, with a faster response speed, the droplet can be divided into multiple stages of control. For the CO2 gas shielded welding, the splash can be drastically reduced, and the stability of the jet transition can be effectively controlled by the pulsed MIG / MAG welding. The droplet transfer and the movement of the wire feed mechanism can also be combined to further control the melt Drip process, get a good weld forming, welding performance and stability. These are the traditional rectifier welding machine can not do.

5.3 centralized control

A large number of welding machine using single-chip, DSP, FPGA and other digital controller, through the Ethernet, field bus to achieve multiple welding machine or the host computer and the network communication between the welding machine. Not only to solve the problem of multiple welding machine co-operation to facilitate the centralized control of the welding process, but also to achieve the remote welding machine parameter settings or monitoring, so that welding machine remote fault diagnosis and maintenance possible.

6. Advantages and disadvantages

6.1 Advantages

Electric welding machine to use electric energy, the instantaneous conversion of electrical energy into heat, electricity is very common, welding machine suitable for working in a dry environment, do not need too much demand, because of small size, simple operation, easy to use, faster, Stitching and other advantages are widely used in various fields, especially for the requirements of the high strength of the pieces of special practical, you can instantly the same kind of metal materials (but also the dissimilar metal connection, but the welding method is different) permanent connection, After heat treatment, the same strength as the base metal, sealed very well, which to the storage of gas and liquid containers to solve the problem of sealing and strength.

6.2 Disadvantages

Welding machine in the process of welding around the welding will produce a certain magnetic field, arc burning will produce radiation around the arc in the infrared, ultraviolet light and other light species, as well as metal vapor and soot and other harmful substances, so the operation must Do enough protective measures. Welding is not suitable for high-carbon steel welding, due to welding weld metal crystallization and segregation and oxidation process, for high-carbon steel welding performance is poor, easy to crack after welding, resulting in hot cracks and cold cracks. Low-carbon steel has a good welding performance, but the process should also be properly handled, rust cleaning is more cumbersome, and sometimes the weld will appear slag cracks and other defects in the hole, but the operation will reduce the defects properly.

7. Introduction to cold welding

7.1 Introduction

1, cold welding repair machine Scope: cold welding repair machine is casting pinhole, trachoma, stomata, cracks, bumps, scratches, pits and mechanical surface wear, mold wear and other small defects in the professional precision welding equipment. Widely used in mold industry, casting industry, electrical manufacturing, medical equipment, automobiles, shipbuilding, boilers, construction, bridge construction and other industries.

2, cold welding repair machine Applicable materials: cold welding repair machine using ordinary wire as a material material: gray iron, ductile iron, stainless steel, carbon steel, die steel, aluminum, aluminum, copper, etc. as long as the conductive metal Can be repaired.

7.2 Features

(1) low temperature constant temperature welding, the matrix does not heat, does not produce thermal deformation, welding near the microstructure unchanged, no stress, no cracks, no hard hardening phenomenon, does not affect the mechanical processing performance.

(2) simple operation, a multi-purpose machine. In addition to surfacing repair function, but also can be tungsten carbide and other hard alloy surface coating to strengthen.

(3) argon gas protection is good adhesion, high welding strength, metallurgical combination, the material and the matrix at the same time after melting and then solidification, combined with a solid, dense, do not fall off. Welding can be carried out after the car, milling, planing, grinding and other mechanical processing.

(4) a wide range of welding wire, economical and practical, the whole machine about 30KG, online repair.

(5) rotary self-loss electrode deposition welding, easy operation, high efficiency.

(6) environmental pollution. No harmful gas generated, can be directly hand, eyes, welding accuracy, welding point is small, small amount of repair after welding.

(7) welding process for the high-frequency welding point of repeated melting accumulation, regardless of the size of the defect, as long as the pen can touch the place can be repaired.

(8) pure metal repair, no welding traces, welding effect to meet the quality standards.

8. Welding operation specification

8.1 Connection check

After completing the welding of the welding machine, it is necessary to check each of the installed connectors to confirm that the connection is good before starting the operation of the equipment. Its contents include:

– line connection is correct and reasonable, grounding must meet the requirements;

– magnetic workpiece jaws in its contact surface shall not have attached metal particles and spatter;

– The welding cable of the coil should be unfolded before use to avoid overheating and insulation damage;

– The need to alternate the length of the cable should be equipped with insulated connectors to ensure that the length is not required when the useless can be disconnected.

8.2 Leakage

There shall be no leakage of any cooling water, protective gas or oil that affects the safety of the welder.

8.3 work is suspended

When the welding work is terminated (such as: work break), you must turn off the output of the equipment or welding machine or cut off the power supply.

8.4 mobile welding machine

When you need to move the welder, you must first cut off the power from its input.

8.5 Not used equipment

Metal electrodes and carbon must be removed from the welding tongs when not in use to eliminate the risk of electric shock to persons or conductive objects. The welding tong must be placed in contact with persons, conductors, flammable objects or compressed air bottles when not in use. Semi-automatic welding machine welding guns must also be properly placed when not in use to avoid accidental start of the gun body switch.

8.6 Maintenance

All arc welding equipment must be maintained at any time to maintain a safe working condition. When the equipment is defective or safe, it must be discontinued until its safety is guaranteed. Repairs must be carried out by authorized personnel.

9. Frequently Asked Questions

1, why the welding plate with energy storage welder suitable, and thick plate suitable for welding arc welding?

In most cases, the energy storage stud welding is suitable for welding on a sheet, and the arc stud is suitable for welding on a thick plate.

Energy storage stud welding is characterized by high current (several thousand A) short time (1-3 ms), so the pool is shallow, welding deformation is also small.

But the welding strength is still relatively large (welding strength> the strength of the stud itself> the strength of the plate itself, or the welding strength> the strength of the plate itself> the strength of the stud itself), so the first yield is the stud (bending or fracture) or Plate (tear).

If the use of energy storage studs on thick plates, then the strength of the plate itself is the largest, because almost impossible to be torn, then the first yield may be studs (stud diameter is small, but rarely Thick plate welded small diameter studs) or welded joints.

There is also a reason that energy storage stud welding can not be welded on hot rolled plates (thicker oxide present), while thick plates are hot rolled plates in most cases.

The current of the arc stud is relatively small (500-1500A), but the welding time is longer (5-2000 ms), so the molten pool is deep and the welding deformation is larger.

Deeper baths If the welded sheet is likely to cause penetration (when welding large diameter studs), the minimum plate thickness is generally required to be 1/4 of the stud diameter.

The deeper baths make the weld strength always greater than the strength of the stud itself, so the first to yield in a destructive experiment is always a stud or sheet.

2, stud welder test, how to understand the “welding strength is greater than the strength of the plate and the stud itself”?

This sentence is mainly for welding strength test to illustrate.

In the case of destructive tests, if the sheet is torn or pulled through, the stud welded part is not separated from the plate, then the stud welding strength is greater than the plate itself strength.

If the stud is broken or bent, the stud welded part is not separated from the plate, then the strength of the stud welding is greater than the stud itself strength.

10.Other references

Mold
Stamping Machine
Mould Design
Injection Moulding Machine
CNC Engraver
Gantry Milling Machine
Milling Cutter
CNC Turning Machine
Universal Milling Machine
Horizontal Milling Machine
Vertical Milling Machine
Tapping Machine
Water Jet Cutting Machine
Plasma Cutting Machine
EDM – Electrical Discharge Machining
ERP – Enterprise Resource Planning
CAM – Computer Aided Manufacturing
CAD(Computer Aided Design)
cnc-milling-machine
cnc router
cnc-lathe-machine-buyers
3d-printer
cnccomputer-numerical-control
cnc-grinding-machine
cnc-drilling-machine
cnc-machining-center
5-axis-cnc-machine
cnc-machining

11.List of Mold manufacturers

Max Müller Schweisstechnik
Swiss manufacturer of welding machines, solutions in the area of ​​thermal joining or separating, pressure regulator and gas equipment for welding, cutting, brazing, heating and straightening.

Weldsale Company
US manufacturer of welding platens, welding tables, acorn style tables, turning rolls, welding machines, cutting machines.

Reviews