1 vertical external characteristics of power, when using positive polarity direct current (wire then negative)

(2) the following general for 6mm sheet welding, with weld appearance, the characteristics of a small amount of welding deformation

3 shielding gas is argon, 99.99%. When the welding current of 50 ~ 150A, the argon gas flow of 8 ~ 10L/min, when the current is 150 ~ 250A, the argon gas flow of 12 ~ 15L/min.

4 tungsten from conspicuous length of the gas nozzle to 4 ~ 5mm better, sheltered in fillet welding and other poor areas is 2 ~ 3mm, deep in the slot where the 5 ~ 6mm, the distance from nozzle to work is generally not more than 15mm.

5 holes to prevent the emergence of welding, welding parts, if any rust, oil, etc. Be sure to clean up.

6. Welding arc length, welding ordinary steel, to 2 ~ 4mm better, and Stainless Steel Electrode, with 1 ~ 3mm better, too long the protective effect is not good.

7 docking primer, in order to prevent the bottom of the back of the weld is oxidized, the back also need to implement gas.

8 For the protection of argon gas well weld pool and to facilitate the welding operation, the tungsten center line of the workpiece and welding should generally be maintained at 80 ~ 85 ° angle, the angle between the surface of filler wire and the workpiece should be as small as possible, usually 10 ° or so.

9. Windproof and ventilation. Windy place, you are requested to take measures to block network, and in the indoor ventilation should take appropriate measures.

Stainless steel MIG welding points and notes

1 with flat features welding power supplies, DC used the anti-polarity (positive wire connection)

(2) generally use pure argon (99.99%) or Ar +2% O2, flow to 20 ~ 25L/min appropriate.

3 arc length, stainless steel MIG welding, spray transfer is generally the conditions down in welding, arc voltage to be adjusted to the extent of the 4 ~ 6mm.

4. Wind. MIG welding susceptible to the influence of wind, sometimes the breeze and have holes, so wind speed over the place in 0.5m/sec, all precautions should be taken.

Stainless steel flux-cored welding points and notes

1 with flat features welding power, welding using DC reverse polarity. Use of general welding CO2 welding can, but please wire wheel slightly loosen the pressure.

2 shielding gas is usually carbon dioxide, the gas flow rate to 20 ~ 25L/min more appropriate.

3 nozzle and the distance between the workpiece to 15 ~ 25mm is appropriate.

4 dry elongation, the average  Welding Wire of 250A below about 15mm, 250A above about 20 ~ 25mm is more appropriate.
Category: News>> Welding Technology

Model

GMT-ZT20 cast iron welding rod
Stamping die welding on cast iron block, welding layer of martensite, excellent wear resistance.
GMT-ZT30 cast iron welding rod
Applied to gray cast iron, ductile iron welding, machining performance is good. Intensity is twice as common electrode.
GMT-ZT40 cast iron welding rod
Stamping die welding on cast iron block, welding layer of martensite, excellent wear resistance.
GMT-ZT50 cast iron welding rod
  Buffer layer is mainly used for rendering. High strength
  GMT-ZT60 cast iron welding rod
Low-temperature welding, mainly used for making hard surface rendering buffer layer.
GMT-ZT65 cast iron welding rod
  Mainly used for cast iron, alloy cast iron, steel and cast iron welding

Drug by the welding electrode core and the skin of two parts. Metal welding electrode is external to the core coating (drug skin) evenly painted welded to the core carefully pressed on. Different types of welding rod, welding core is different. Welding electrode core that is metal core, in order to ensure weld quality and performance, welding metal elements of the core content of each there are stringent regulations, especially of harmful impurities (eg sulfur, phosphorus, etc.) content, there should be strict limitations, better than the base metal. Welding core components directly affect the weld metal composition and performance, so welded to the core of the harmful elements in as little as possible. With C content should be less than 0.10%. For example, H08A, with S less than or equal O. 03%, P less than or equal 0.03%, C is less than equal to 0.1%.
Welded carbon steel and low alloy steel welding core, low-carbon steel is generally used as a welding core, and fill up the manganese, silicon, chromium, nickel and other ingredients (see the national standard GB1300 an 77 wire). The reason one hand, low-carbon low carbon steel wire plastic, wire drawing easier, on the other hand reducing gas to reduce CO content to reduce spatter or porosity, and increased the temperature of the weld metal solidification, beneficial to the overhead position welding. Other major alloying elements added to ensure the weld mechanical properties, while the Stainless Steel Electrode performance and to remove impurities, also have a role.
High-alloy steel and aluminum, copper, iron and other metal materials, its core components in addition to welding and welded metal similar requirements, but also have control of impurities, according to process requirements often adding certain alloying elements.
Electrode is coated with a drug for skin melt welding electrodes used in arc welding. It is a drug and the skin-core solder composed of two parts, shown in Figure 3-5. Drug in the skin with the front electrode 45. Around the chamfer, which is to facilitate the arc. In the rear there is a bare core welding, welding rod length of about 1 / 16, to facilitate the welding clamp holding and help conduct electricity. Chung electrode diameter is actually welded core diameter) is usually 2,2. 5,3 2 or 4, 5 or 6mm and other types of specifications, used a small 3.2 small 4 small 5 three species, its length "L" is generally between 250 ^ -450 mm.
 
  1. Welding core
  Electrode was covered medicine bag welding the metal core as the core. Welding Wires  core is generally a certain length and diameter of the wire. Welding, welding core has two effects: first, conduction welding current, arc to convert electrical energy into heat energy, the second is filled with weld metal core itself is melted as the liquid base material with the formation of the weld metal fusion.
Welding electrodes, welding metal core part of the total weld metal. So the chemical composition of welding core {a direct impact on the quality of the weld. Therefore, as the electrode core wire is a single potential with the provisions of its independence and composition grades. If used for submerged arc welding, electroslag welding, gas welding, gas welding method for welding filler metal, then known as the wire. (1) welding in the core of the effects of alloying elements on the welding
1) carbon (C) Carbon is the main alloying elements in steel, when the carbon content increases, the steel {strength, hardness markedly improved, and the plastic lower. In the welding process, the carbon oxygen play a role in the arc under high temperature and oxygen compounds, generating carbon monoxide and carbon dioxide gas, the air around the arc and weld pool exclusion zone to prevent air oxygen and nitrogen gases adverse impact on the pool, reducing the weld metal oxygen and nitrogen. If the carbon content is too high, to restore the role of severe, will cause a larger splash and pores. Taking into account the carbon steel hardened to the crack and its increased sensitivity to the effects of low-carbon steel welding core of the general cluster 0.1%.
2) Manganese (Mn) of manganese in the steel alloy is a good agent, with the manganese content increases, the strength and toughness will be increased. In the welding process, the manganese is also a good dose of oxygen, can reduce the oxygen content in the weld. Together with the formation of manganese sulfide in the slag floating manganese sulfide, thereby reducing the weld hot cracking tendencies. Therefore, carbon structural steel welding core general's manganese content is 0.30% ~ 0.55%, some special-purpose wire welding, the manganese content of up to 1. 70% to 2.10%.
3) Silicon (Si) silicon is a good alloying agent in steel by adding an appropriate amount of silicon can increase the steel yield strength, flexibility and acid resistance; if the content is too high, reduce the plasticity and toughness. In the welding process, silicon also has good oxygen capacity, and oxygen to form silicon dioxide, but it will increase the slag viscosity, easy to promote non-metallic inclusions generated.
4) Chromium (Cr) chromium steel to improve hardness, wear resistance and corrosion resistance. For low carbon steel, the chromium is a kind of accidental impurities. The main features of chrome is easy to rapid oxidation of metallurgy, the formation of refractory oxides of chromium oxide (Cr203), which increases the likelihood of weld metal inclusions. Transition to the chromium oxide slag, the slag viscosity can improve, lower liquidity.
5) Ni (NO nickel on the toughness of the steel has a relatively significant effect, generally require a higher temperature impact value, the appropriate incorporation of some of the nickel.
6) Sulfur (S) Sulfur is a harmful impurity, with the sulfur content increases, the tendency to increase weld hot cracking, so the welding core sulfur content of no greater than 0.04%. Important in the welded structure, the sulfur content not more than 0.03%.
7) P

(2) the classification of welding core

Welding core is based on national standards, "welding wire" (GB 1300-77) classification requirements for welding steel wire can be divided into carbon steel, alloy steel, stainless steel three categories.

2 drug skin
Pressure applied to the welding surface of the coating is called the core drug skin. Drug skin electrodes in the welding process plays an extremely important role. The use of a drug-free light skin electrode welding, the welding process, oxygen and nitrogen in the air will be a substantial intrusion of molten metal, the metal iron and beneficial elements carbon, silicon, manganese oxide and nitride formation of various oxides and nitride, and left in the weld, causing the weld slag or cracks. And melt into the pool of gas may produce large amounts of weld porosity, these factors can make the weld mechanical properties (strength, impact value, etc.) greatly reduced, while the weld brittle. In addition, the use of optical electrode welding arc is very unstable, serious splash, poor weld. It found that in practice outside the electrode coated with a layer of light from a variety of minerals and other components of drug skin, can burn arc stability, weld quality is improved, this electrode is called coated electrodes. With the continuous development of industrial technology, it created a now widely used high-quality thick coated electrodes.