The choice of parameter of craft of cut of machine of numerical control Plasma Cutting

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One, cut electric current: It is the most important cut craft parameter, decided the ply of cut and rate directly, namely cut ability. Cause an effect: 1, cut electric current increases, electric arc capabilities adds, cut ability rises, cut speed is to increase electric current of;2, cut subsequently, electric arc diameter increases, electric arc coarsens make cut broadens electric current of;3, cut crosses an ambassador to get nozzle thermic load to increase, nozzle is injured prematurely, cut quality nature also drops, cannot undertake be cuttinged normally even. Want to choose cut electric current and corresponding spray head correctly according to the ply of material before cut so. 2, cut speed: Limits of optimal cut speed can show make choice of according to equipment or decide with the experiment, because the thickness of material is spent, material differs character, melting point discretion, the element such as thermal conductance size and the exterior tension after fusing, the change with cut corresponding also rate. Main show: 1, cut speed carries high-energy improvement moderately cut quality, namely cut somewhat narrow, cut surface more level off, can reduce at the same time be out of shape. 2, cut speed makes too quickly the value of a quantity that the line capabilities of cut requires under place, cut the efflux in seaming to will fused cut fuse-element blows off instantly and cannot form bigger drag quickly, companion hangs broken bits as cut, cut surface quality drops. 3, when cut when rate is too low, because cut is in the positive pole that is plasma arc, to maintain the stability of electric arc oneself, zincous stain or in relief polar region should be in those who leave electric arc the closest to cut necessarily seam around find conduction current place, can deliver more quantity of heat to the radial of efflux at the same time, because this makes cut broadens, the material of two side melt is in cut hemline gathers and caky, form what clear not easily to hang broken bits, and because cut upper edge heats fused and overmuch and form round part. 4, become when rate is extremely low, because cut is too broad, electric arc can go out even. This shows, good cut quality and cut rate are not assigned. 3, electric arc voltage: Think power source outputs voltage to be cut voltage namely normally commonly. Machine of plasma arc cut has taller sky to carry voltage and working voltage normally, in use ionization can expensive gas is like nitrogen, hydric or when air, the voltage that stabilizes plasma arc place to need will be taller. When electric current is constant, of voltage raise those who mean cost of electric arc enthalpy with cut ability rise. While if be in,enthalpy value increases, reduce the diameter of efflux and increase aeriform velocity of flow, often can acquire rapidder cut rate and better cut quality. 4, working gas and discharge: Working gas includes cut gas and auxiliary gas, some equipment still ask to remove arc gas, want the sort according to cut material normally, ply and cut method will choose appropriate working gas. Cut gas should assure the formation of plasma efflux already, want to assure the melt metal in purify cut and oxide again. Too large gas flow can take away more electric arc quantity of heat, make the length of efflux shortens, bring about cut ability to drop with electric arc the aeriform flow with flabby too little; makes plasma arc is lost some is spent straight and should make the deepness of cut becomes shallow, at the same time easy also generation hangs broken bits; so aeriform discharge must cooperate very well with cut electric current and speed. Machine of present plasma arc cut relies on aeriform pressure to control flow mostly, because time when aperture of gun put oneself in another's position, controlled aeriform pressure to also control flow. Cut is definite board the data alternative that the aeriform pressure that thick stuff place uses should offer according to equipment manufacturer normally, when be like the special application that has other, aeriform pressure needs to decide through actual cut experiment. The most commonly used job gas has: Argon gas, nitrogen, oxygen, air and H35, argon - nitrogen gas mixture. 1, argon gas produces reaction with any metals scarcely when high temperature, argon enrages plasma arc very stable. And uses spray head and electrode have taller service life. But the voltage that argon enrages plasma arc is inferior, enthalpy cost is not high, cut ability is limited, the ply that compares its cut with air cut photograph can be reduced about 25% . Additional, in environment of argon gas protection, the exterior pulling force of fused metal is larger, want to issue tower above than the environment is being enraged in nitrogen about 30% , can have the more problem that hang broken bits so. Although use the mixture gas of argon and other gas,cut also can have tendency sticking broken bits. Accordingly, already used pure argon gas to undertake Plasma Cutting alone rarely now. 2, hydric it is to serve as auxiliary gas and action of other gas mix up normally, like famous aeriform H35(hydric bulk mark is 35% , the others is enraged for argon) it is one of gas with the strongest capability of plasma arc cut, this main Yu Qing that get benefit is angry. As a result of hydric can heighten electric arc tension significantly, make hydrogenous plasma efflux has very high enthalpy cost, should mix with argon gas when using, the cut ability of its plasma efflux rises greatly. Be opposite commonly the metallic stuff of ply 70mm above, commonly used argon + hydrogen regards cut as gas. If use water efflux to argon + arc compresses hydric plasma further, still can achieve taller cut efficiency. 3, nitrogen is a kind of commonly used job gas, below the requirement that has voltage of taller power source, arc has nitrogen plasma better stability and higher than argon gas efflux energy, even if the stuff with old viscosity of metal of cut liquid state is mixed like stainless steel when nickel radical alloy, the quantity hanging broken bits of cut lower edge is very few also. Nitrogen can be used alone, also can use with other gas mix up, if nitrogen or air often are used to regard the job as gas when automation cut, these two kinds of gas had made the standard gas of carbon steel of high speed cut. Sometimes nitrogen still is used as oxygen plasma the gas removing arc when arc cut. 4, the rate that oxygen can raise material of cut mild steel. When use oxygen has cut, cut mode and blaze cut very envisage, the plasma arc with high-energy high temperature makes cut rate rapidder, but must cooperate to use the electrode that fights high temperature oxidation, when undertaking removing arc to electrode at the same time prevent concussion protection, in order to prolong the life of electrode. 5, bulk mark is contained to make an appointment with the nitrogen of 78% in air, the case hanging broken bits that uses air cut place to form so and when using nitrogen cut very bulk mark still is contained to make an appointment with the oxygen of 21% in envisaging; air, because of the existence of oxygen, very tall also; is the same as the rate that uses data of airy cut mild steel spatio-temporal gas also is most working gas of economy. But when cut of alone use air, can have hang broken bits and cut oxidation, add the problem such as nitrogen, and the life of electrode and nozzle is inferior also can affect work efficiency and cut cost. 5, nozzle height: Point to the distance of nozzle end panel and cut surface, it made the one part of whole arc length. Use constant current commonly as a result of plasma arc cut or steep the power source of the feature outside falling, after nozzle height increases, voltaic change is very little, but can make arc length increases and bring about electric arc voltage to increase, make electric arc power raises; thereby but also can make reveal the arc length growth in the environment at the same time, grow in quantity of energy of arc column losing. In two elements the circumstance of integrated action falls, former action often is offsetted completely by latter place, can make effective cut energy is reduced instead, cause cut ability to reduce. Behave be cut efflux to blow force normally abate, the slaggy grow in quantity that cut bottom remains, upside brim crosses frit and appear round horn. Additional, from the configuration respect regard of plasma efflux, after leaving muzzle, efflux diameter is expanding outwards, the addition of nozzle height causes cut width to increase necessarily. So, choosing hidebound nozzle height is beneficial to improving cut speed and cut quality, but, double arc appearance may be caused when nozzle height is too low. The nozzle outside using pottery and porcelain can set nozzle height for 0, namely spout end panel is contacted directly by cut surface, can achieve very good result. 6, cut power density: Shrink to obtain high pressure electric arc of plasma arc cut, cut nozzle used lesser opening diameter of nozzle, longer orifice throat length to enhance cooling result, can make nozzle effective so the electricity that carries inside section increases, namely the power density of electric arc increases. But compress at the same time also make the power loss of electric arc is increased, accordingly, the power that the effective energy that is used actually at cut should want to be outputted than power source is little, its loss late is commonly between 25%~50% , the energy loss late that if water reduces plasma arc cut,has some of method will be bigger, making this issue should consider when the economic accounting of design of cut craft parameter or cut cost. Citing: The plate that uses in industry is thick it is to be under 50mm mostly, the plasma arc cut that uses convention inside this ply limits often can be formed go up big to cut a mouth smally, and cut a mouth above the predestined relationship still can bring about cut dimension to precision drops and increase follow-up treatment to measure. Should use oxygen and nitrogen plasma when steel of arc cut carbon, aluminium and stainless steel, when board thick inside 10~25mm limits when, it is material normally thicker, the verticality by the side of end is better, the angle error of edge of its cut arris is spent in 1 degree of ~4. When board thick be less than 1mm, along with board reduce thickly, cut angle error is spent from 3 degrees of ~4 increase 15 degrees of ~25 to spend. Think commonly, because the plasma efflux heat on the face that cut a mouth inputs lopsided be caused by,the generation reason of this kind of phenomenon is, be in namely the upside plasma that cuts a mouth of arc energy release over bottom. What this energy releases is lopsided, with parameter of a lot of craft closely related, if plasma arc reduces rate of degree, cut,reach nozzle to wait to the distance of workpiece. The compression that increases electric arc degree can make efflux of high temperature plasma is lengthened, form more even high temperature area, increase the rate of efflux at the same time, the width that can reduce cut to fluctuate is poor. However, of groovy nozzle excessive compress often can cause Shuang Hu appearance, shuang Hu not only meeting loss electrode and nozzle, make cut process cannot undertake, and the fall that also can bring about cut quality. Additional, too old cut rate and too great nozzle height can cause what cut fluctuation width differs increase. High-powered Rapier and system of Plasma Cutting of Trident numerical control centered HG-FARLEY LASERLAB before achievement of science and technology, used brand-new gas to control box design, provided superior cut quality and quality stability for the user, the biggest the manufacturing efficiency that change, the smallest moving cost, unapproachable treatment applicability, can acquire quality of finer than departed and much better essence cut with the moving cost of the half. When cut carbon steel, have the careful feature part of superior quality and stability. Combine the cut bed of high accuracy, can get admirable small are mixed round hole quality. When cut stainless steel and aluminous material, use N2/N2, h35(argon hydrogen mixes air beforehand) with craft of H35 – N2, and hydrogen of new F5 (nitrogen mixes air beforehand) craft, make laminose cut quality rises apparently. CNC Milling CNC Machining