Plasmatron. Requirements for Plasmatron

this article helps to understand - based on what the requirements are designed torches, the conditions under which they operate.

In the design of plasma torches for different types of data processing should take into account a number of general requirements for it:

1. The plasma torch should provide multiple reliable ignition and stable combustion of the plasma arc in a given range of operating currents and voltages. This requirement is satisfied for certain relationships between the diameter of the electrode, nozzle, the length of the latter, and the gap between them, and with proper constructive solution of the host formation and stabilization of the arc.
2. Elements that are particularly susceptible to heat (electrode tip), must withstand prolonged heat load at the maximum power of the plasma torch. This requirement is satisfied by proper choice of material is heat-stressed cells and of the system of cooling.
3. Electrical isolation between the electrodes and the nozzle should be designed for the maximum voltage appearing at the arc gap in the excitation of the arc and its breakage. Upon excitation of the arc with the oscillator voltage is 2-5 kV in the frequency range 0.3-1 MHz.
4. The elements of water and gas supply of the plasma torch (hoses, seals, gaskets, etc.) must withstand a pressure below 10 atm.
5. To ensure the maneuverability it connects to the plasma torch hoses and electrical wires should be flexible and durable.
6. The plasma torch should be technologically advanced in the manufacture, repair and easy to use. It is particularly important to ensure ease of disassembly and assembly, and the ability to quickly replace the most commonly wear parts (cathode and nozzle).
7. The design of plasma torch should be cost-effective, ie it must be capable of nedifitsitnyh materials for its manufacture and to ensure a minimum intake of cooling water, the working gas and the minimum heat loss.
8. For plasma torches is presented and a number of specific requirements arising from the peculiarities of the process.
9. Plasma torches for welding and surfacing must provide protection from the harmful effects of the joint environment, plasma torches for spraying - high flow rate and enthalpy of the plasma jet with a minimum of contamination of the products of electrode erosion, cutting torches - a high concentration of heat flow of the plasma jet. Manual plasma cutter should be easy to use.

The design of melting torches, designed for use in a furnace with a high temperature of the atmosphere, must provide the following specific requirements:

1. the absence of any water, electric or gazopodvodyaschih hoses in the working space of the furnace;
2. water cooling of metal parts;
3. protection against radiation of all seals and nonmetallic parts, or water-cooled thermal insulation screens;
4. the possibility of entering the plasma torch in the furnace chamber through the seal.

It is desirable to provide an opportunity to move forward in the chamber during operation.
In some cases, special requirements to the system control plasma torch, a method of cooling, to protect against environmental influences, to its high reliability in operation on the production line, etc.

See also:
Plasma Welding
Plasma Welding Introduction
Plasma Welding Technique
Microplasma Welding
Gases for plasma processing of materials
Separation of plasma jet cutting
Compression of the arc
The energy properties of the plasma arc
Rationalization of plasma welding
Plasma welding and spraying
The plasma melting and remelting
Plasmatron. Requirements for plasmatron
Plasmatron. Schemes, classification
Classification by type of electrode plasma torches
Classification of torches by the nature of the current
Structure of the plasmatron basic units