Balance disc stacker welde

Product alias:	plasma powder heap welder
current:	DC
purpose:	fusion
object of action:	metal
principle of action:	inverter
arc current:	2-300 a
maximum output load rate:	70%
dimensional arc current range:	2-20 a
pulse frequency range:	50 Hz
ionic gas flow:	0 2-2 5 L / min
brand:	Shanghai duomu
model:	dml-v03bd

characteristics of plasma powder stack welding machine
1
  Technical features: the plasma arc used in the plasma powder stack welding machine is an ionizing arc, which is more concentrated than the arc welding machine, so the heating speed is faster
In order to obtain more concentrated ion beam, it is generally used with high compression ratio aperture and low current, so as to control the substrate temperature from being too high and avoid annealing deformation
Of course, this is incomparable with the heating speed of YAG laser
Because the plasma arc works continuously, the cooling of the body is relatively slow, and the formed transition area is deeper than that of laser cladding, which will release the stress better for the cladding of hard surface materials

2
  Equipment features: plasma powder surfacing equipment is developed on the basis of DC welding machine
Its power supply, surfacing gun, powder feeder and swing device have low technical threshold, easy manufacture, good reliability, simple maintenance and use, low power consumption, low use cost, good universality, low production cost, good adaptability, easy large-scale production, remarkable benefits and low environmental requirements, Wide adaptability to materials
With the progress of electrical technology, the technical level of welding machine in China has enough support capacity
In addition, the equipment has small volume and weight, and the welding gun can be held by hand, which makes it more flexible and convenient to use, and the cost of auxiliary tooling is cheap

3
  Process characteristics:
First Simple preliminary treatment: just remove rust, dirt and fatigue layer

Second Powder feeding: argon powder feeding is adopted, with low feeding accuracy and certain inclination
This allows manual operation, which is more suitable for metal repair

Third, the stability of plasma arc is good: the formation of molten pool is also easy to control, the cladding is fully integrated with the body, and the excessive area is good

Fourth The heating and cooling rate is lower than that of laser: the melting state lasts for a long time, which is conducive to the uniform formation of metallographic structure, and the exhaust scum is better
It has been heated during the powder ejection process, and is protected by argon and ionic gas
Therefore, the uniformity of cladding layer is better, and there are fewer defects such as pore slag inclusion

Fifth Material selection: plasma powder surfacing technology has less restrictions on materials, wider material selection, and easier surfacing of carbides and oxides

3、 Some problems in plasma powder surfacing
1
  About welding stress: we must establish a concept
No matter what terms are used (such as welding, surfacing, spray welding, cladding, etc
), they are melting and casting on the metal substrate under heating, so stress will inevitably occur in the process from heating to melting and casting, and then to cooling
In addition to very special materials, the shrinkage stress is generally the most affected
Different welding methods are different from heating methods, speed, filling materials and some other conditions
Therefore, reducing the influence of this stress on the matrix and casting layer is an important aspect to be considered when we pursue welding quality
Shrinkage stress cannot be avoided, so stress release is the key to solve the problem of welding stress
In other words, where to release the shrinkage stress and how to distribute the stress from the body to the casting area are the problems we need and can solve

2
  Why the deformation of laser welding (cladding) is small: mainly due to small melting and casting area, small transition area and small shrinkage
Then the shrinkage force produced by the material in the shrinkage process is not enough to deform the whole body
This is the reason why the so-called laser cladding does not change (so it will also deform when the body size is too small)
This is also the advantage of laser welding (cladding)
So where is the welding stress? It is mainly released to the casting area and transition area
Then two problems arise
First, cracks are easy to occur in the melting and casting area, so laser cladding has high requirements for the ductility of materials, such as nickel based powder; Second, the stress in the transition zone is large
Due to the rapid heating and cooling in the process of laser welding, the size of the transition zone is too small, resulting in the stress concentration in this area, which affects the bonding effect of laser welding (cladding)
Especially when the mechanical properties of matrix and welding material are quite different, the tendency is more serious, and even falling off occurs, which requires special attention to the material and thickness design of transition layer during laser cladding

3
  Why plasma powder surfacing is not easy to produce defects such as cracks and pores: there are three main reasons
First, plasma is used as the heat source for surfacing
Compared with submerged arc welding, plasma heat is more concentrated, ion arc stability is better, there is no electrode melting consumption, and the output heat is uniform, which is easy to control
In this way, the heat distribution in the melting and casting area is uniform, the material fusion is sufficient and uniform, the exhaust floating slag is sufficient, and the shrinkage stress is evenly distributed
Second, due to the high control precision of plasma equipment, it is convenient to control the melting and casting area and transition area, with good uniformity, easier and reasonable stress distribution
Third, argon protection does not require various additives, and there are no problems such as hydrogen emission and oxidation
Therefore, plasma surfacing is more suitable for high-quality hard surface melting and casting (such as high manganese and high chromium ceramic materials)
It is suitable for manufacturing wear-resistant plates, valves, rolls, etc