What is the best welding method for pig iron? Transmission housing

If it is a welding gearbox shell, we must pay attention to the thermal impact of welding, design the most reasonable groove, considering the welding importance of this shell, it is recommended to use imported special cast iron electrode wewelding777 cast iron electrode welding, although the cost is a little higher, but for maintenance, the consumption is not as large as the production, so it is worth it on the basis of ensuring the success rate.

What kind of welding rod is wewelding777 cast iron electrode for maintenance?

1. AWS SFA standard, American special maintenance welding consumables.

2. It is suitable for all kinds of cast iron (including ductile iron, gray iron, high CR maintenance welding), as well as dissimilar welding of cast iron and steel.

3. It is used for low-pressure water welding of cast iron pipes.

4. Alloy metal welding core design, coated with unique flux, with anti-cracking function.

5. The weld deposition layer can be machined.

What is wewelding777 used for?

Welded cast iron and steel, welded with different cast irons Transmission gearbox.

Grey cast iron, malleable cast iron or ductile iron sewer pipes.

Wewelding777 technical parameters.

Tensile strength: 70,000 psi (482 Nv. mm²).

Yield strength: 62,000 (427 Newtons square mm²).

Hardness (HB): 185HB Color matching with base metal: similar.

Power selection: AC and DC dual-purpose, DC reverse connection when DC.

Process parameters. Diameter (mm).

Current (amps) 60-100 85-110 90-140

Wewelding777 Tips for Using Processes.

1. It is necessary to do proper surface cleaning before welding, and the welded joint should be obliquely cut into a U-shaped groove.

2. Crack holes at both ends of the crack to prevent the expansion of the crack during the welding process.

3. When the repair angle is not good, you can choose the wewelding100 electrode cold slotting to form an effective U-shaped or V-shaped groove.

4. Weld with as little current as possible, medium arc length, and slightly inclined to the welding direction.

5. It is recommended that the weld bead should be short, thin and narrow transversely oscillating torch to fill the weld before stopping the arc welding, usually without heat treatment, allowing the parts to cool slowly.

Cast iron welding, transmission housing. MG289 cast iron electrode is selected, cold welded. The working environment of the transmission is harsh, the vibration is strong, and there may be oil stains in the welding parts.

MG289 cast iron electrode has sufficient strength, suitable for dirty cast iron welding, tensile strength and crack resistance can be good for welding the cracking and damage parts of the transmission.

At present, there are many fakes in the market, so it is recommended to find regular enterprises and buy them through formal channels to avoid irreparable losses due to fakes to weldments.

Welding pig iron according to the conventional welding method is required to have certain welding conditions, such as tools or equipment that need to be preheated, and then there is a furnace or lime pile that is slowly cooled after welding, if this condition is met, the pig iron can be preheated after 600 degrees, and then the heat preservation and slow cooling after welding can be, this kind of pig iron parts suitable for non-important value, especially small pig iron parts for household use.

If it is an important cast iron equipment, such as the factory's gearbox, engine body, water pump installation, etc., the crack or fracture repair of such important cast iron equipment is recommended to be welded by cold welding process, and the wewelding777 cast iron electrode suitable for cold welding process welding is used, and the tensile strength after welding is up to 480MPa, which is often used for the maintenance and repair of important cast iron equipment in the factory, because fortunately, the consumption of repair is not too much, even if the material cost will be relatively high. But that's very, very small compared to downtime losses.

At present, there are two methods that are commonly used: 1Oxygen is welded with pig iron electrodes, but only for small parts or thin materials.

2.Nickel-chromium electrode (also called pig iron electrode) is used to preheat and re-weld thick pig iron parts under the flame, weld again and again, disperse the welding stress with a hammer, and keep warm after welding.

Generally, gas welding is used, and there are special pig iron electrodes.

I look at the thickness of the pig iron with an appropriate current.

Pig iron electrodes will do.

There are many selectivity of pig iron electrodes, such as carbon steel electrodes J506 electrodes for conventional pig iron welding, conventional cast iron electrodes Z308, and special cast iron electrodes with high crack resistance WeWelding777, and what kind of pig iron electrodes to choose for the welded workpiece depends on the added value and importance of the welded workpiece, if it is a general household small pig iron tool or small parts, you can preheat it at about 600 degrees before welding with a small household electric welding machine, After welding, quickly insulated into the lime pile or ash pile, this is a more economical welding method, and often the factory pig iron equipment does not have such conditions, and the success rate is required to be a high standard, and the pig iron with ordinary cast iron electrode Z308 welding has the risk and probability of cracks, so in order to increase the success rate and reduce the risk of downtime, it is generally important to choose high crack resistance wewelding777 cast iron electrode welding, cold welding process, without preheating and thermal insulation treatment.

At the same time, the welded objects must be heated and insulated, and the temperature of the welded ones must be consistent as much as possible, otherwise the welded objects will have cracks, which will affect the normal use.

If it is gray cast iron, carbon steel or alloy steel welding rod can also be used, which is controlled from the process, generally does not need to be preheated, the groove design minimizes the amount of melted base metal, and small current rapid welding is adopted, intermittent welding, and the interlayer temperature is controlled at 60 degrees -70 degrees. Ductile iron, because it has a greater tendency to whiten and harden than gray cast iron, is best used for pig iron electrodes.

If there is no pig iron electrode for pig iron, it is stronger to weld with this electrode, so learn from the master.

Pig iron is cast iron, and cast iron electrodes can be used.

Common models of cast iron electrodes:

cmc-e46n

cmc-ms64n

cmc-e47n

cmc-e67n

cmc-e65n

How do you weld pig iron? Are you still worried about which electrode to choose? The master shared 2 types of welding rods.

When it comes to cast iron electrodes, everyone must know that because we often encounter fractures in the machine base, cover, etc. in our lives, at this time, we need to use cast iron electrodes to weld the broken parts. Now I will give you a specific introduction to the welding methods and precautions of cast iron electrodes.

One. Thermal welding method of cast iron electrode

The so-called thermal welding method is to heat the cast iron electrode for welding, first of all, before welding, we have to heat all the objects to 600 to 700 degrees, in the welding process, the temperature of the entire welded parts can not be lower than 400 degrees. But after welding, we can wait for it to cool down. The methods of thermal welding are generally gas welding and electric welding, and the tools required are hot furnaces and welding tools.

The process is generally as follows: the first step is to preheat, clean the entire welded part until the metal is exposed, and then put it into the furnace to heat. After that, the welding is carried out, generally with a neutral flame welding, the metal is penetrated, put the welding rod in, and then wait until the white point appears, put the flux in, must be in the appropriate amount, and then continue to weld.

However, in the process of welding, it is necessary to pay attention to smoothing the weld. Finally, it is good to cool it, and pay attention to the cover plate during the cooling process to avoid cracks.

Two. Cold welding method for cast iron electrodes

The welding method of cold welding is generally electric welding. The first step of cold welding and hot welding is the same, first clean up until the metal is exposed, and then start welding, in the process of welding, whether it is the electrode or the current should be as small as possible to avoid wasting the electrode, and it is best to keep the current stable in the process of welding, do not affect the welding because of the temperature. When welding, it is best to follow the principle of first inside and then outside, disperse the welding, weld the first layer in the second layer after welding, and it is best to check whether there are any pores or cracks left when welding.

So careful soldering is good additionally.

Three. Welding precautions

First of all, one of our more important points is that in the process of welding, we must first clean up the debris on it, and for the welding rod of thermal welding, we must also remove the oxide on it. The second is to pay attention to the shape of the crack when welding the crack, choose a good electrode, and another point is that if you choose cold welding, you should also preheat it first, and then choose the appropriate current, and keep the current stable.

The welding method of cast iron electrode is probably like this, but whether it is hot welding or cold welding is a very dangerous process, we should pay attention to safety in the process of welding, and also pay attention to the precautions when welding. The above is a brief introduction to the welding method of cast iron electrode, I hope it can help you!

Welded with iron electrodes.

Covered electrode: A metal strip that melts and fills the joint of the welded workpiece during gas welding or electric welding. The material of the electrode is usually the same as that of the workpiece.

The electrode is a melting electrode coated with coating for arc welding of electrodes, which is composed of two parts: coating and core. According to the provisions of the national standard "steel wire for welding" (GB 1300-77), the special steel wire used for welding can be divided into three categories: carbon structural steel, alloy structural steel and stainless steel.

Welding rod (coveredelectrode) is applied evenly and centripetally to the welding core by coating (coating) on the outside of the metal welding core. In order to ensure the quality and performance of the weld, there are strict regulations on the content of each metal element in the weld core, especially for the content of harmful impurities (such as sulfur, phosphorus, etc.), which should be strictly limited, which is better than the base metal. The electrode is composed of two parts: the core and the coating.

Depending on the type, the core is also different. The composition of the weld core directly affects the composition and performance of the weld metal, so the harmful elements in the weld core should be minimized. For welding carbon steel and low-alloy steel cores, low-carbon steel is generally used as the welding core, and manganese, silicon, chromium, nickel and other components are added (see the national standard G1300-77 for welding wire).

On the one hand, the reason for the use of low carbon is that the steel wire has good plasticity when the carbon content is low, and the wire is easier to draw, on the other hand, it can reduce the CO content of reducing gas, reduce spatter or porosity, and can increase the temperature of the weld metal solidification, which is beneficial to upward welding. The addition of other alloying elements is mainly to ensure the comprehensive mechanical properties of the weld, and at the same time, it also has a certain effect on the performance of the welding process and the removal of impurities. In addition to the similarity of the core composition of high-alloy steel and other metal materials such as aluminum, copper, cast iron, etc., the content of impurities should also be controlled, and some specific alloying elements should be added according to the process requirements.

The electrode is a melting electrode coated with a coating for arc welding of the electrode, which is composed of two parts: the coating and the welding core. The coating at the front end of the electrode has a chamfer of about 45°, which is to facilitate arc initiation. There is a section of bare welding core at the tail, which accounts for about 1 16 of the total length of the welding rod, which is convenient for the welding tong to clamp and is conducive to electrical conduction.

The diameter of the welding rod actually refers to the diameter of the welding core) is usually 2, or or 6mm and other specifications, the most commonly used is small 4, small 5 three, the length of the "l" is generally between 200 550 mm.

Ordinary stress is not large, you can choose Z308 electrode, Z408 electrode, etc., for key important equipment, the force is relatively large, it is recommended to use the United States MG289 cast iron electrode welding can be used. MG289 welding rod (there are many fakes on the market, it is recommended to go to a regular company when buying). The specific performance is as follows:

MG289N is a high-strength alloy for unclean cast iron welding.

n The weld deposition layer can be machined.

n Specially designed for welding unclean, oily cast iron.

n It is used for low-pressure water welding of cast iron pipes.

n Alloy metal core design, coated with unique flux, with anti-cracking function.

n Easy to weld in any position.

n Uses, such as:

Welding of cast iron and steel Welding of different cast irons - Transmission gearbox - gray cast iron, malleable cast iron or ductile iron - Technical parameters of sewer pipes (typical).

Tensile strength up to 60,000 psi (415 Newtons square mm²) and hardness HB210

CHC308 (Z308) electrode is generally used.

Compliant: GB EZNI-1

aws eni-ci

Description: CHC308 is a pure nickel core graphite type coating cast iron electrode, the electrode adopts foreign advanced technology, the coating is black reddish, AC and DC dual-purpose, arc stability, with fine droplet transition, uniform slag coverage, beautiful weld seam forming, especially small current has excellent operation process performance, help avoid the adverse effects of high current welding.

Uses: It is used for the repair welding of thin parts and machining surfaces of castings, such as cylinder heads, engine seats, gearboxes and machine rails and other important gray iron castings.

Notes: 1Stress in the patch zone can be eliminated by hammering the weld seam to avoid cracks.

2.The cold welding of cast iron should avoid the use of high-current welding, so as to reduce the penetration of impurity elements in the base metal into the weld, reduce the width of the white mouth area, and improve the crack resistance and machining ability of the weld.

3.Before welding, the electrode must be baked at about 80-120 0C for 1 hour.