SU889329A1 - Method of powder-lance cutting of metallic and non-metallic materials - Google Patents

Description

heat generation is reduced and this causes cessation of cutting. For the same reason, when cutting thick billets of hard-to-cut alloys and burning through deep holes in non-metallic materials, the flux consumption increases and it requires a high content of aluminum powder, which is also a drawback of the known method. The purpose of the invention is to increase the amount and heat, especially in its initial | period, lowering the temperature barrier, reducing the time spent on the primary and re-excitation of the process, facilitating the propagation cutting into the depth of the material and reducing the yield: the flow rate of the flux while reducing the content of aluminum powder in it. The goal is achieved by the fact that in the proposed method powder spear cutting of metallic and non-metallic materials, in which the tube end is heated to its oxygen ignition temperature and oxygen-flux cutting mixture is fed through the tube, the tube end heating operation is performed by immersion in a liquid alloy on an aluminum base doped with magnesium and titanium, heated above the temperature at which the alloy starts burning in oxygen, but below its ignition temperature in air. In addition, in order to prevent a decrease in the intensity of cutting during the process of cutting materials, in the cutting area: portions of the above-mentioned alloy are introduced. The method is carried out by immersing the end of the tube in an alloy on aluminum bases. This alloy is alloyed with magnesium and titanium and heated above the temperature at which the alloy begins to burn in oxygen, but below its ignition temperature. In the process of cutting, while reducing the intensity of the process, portions of the same alloy are added to the cut cavity. Immersing the end of a spear into a known liquid alloy allows not only to heat it up due to physical Heat from an external source, as it happens in this method, but at the same time apply a layer of heated alloy, aluminum, magnesium and thiHy to the inner and 5th surfaces of the spear when cutting, active interaction with oxygen occurs at lower temperatures than steel, lance and flux powders, and with reactions with large exothermic effects. All this. (As well as the introduction of a liquid alloy directly into the region), Provides a reduction in the temperature barrier of cutting, additional heat generation and an increase in the cutting of the cutting front in depth. An example. Comparative experiments were carried out on the lance-type powder cutting of stainless steel; h18N9T with a thickness of 100 mm and drilling holes in a 80 mm-thick reinforced concrete slab by known and proposed methods. In the known method, iron-aluminum flux consisting of 85% iron and 15% aluminum powder is used, in the proposed method the retention in the flux of iron powder rises to 92%, and the aluminum powder, respectively, decreases to 8%. In the known method, before the start of the oxygen-flux mixture, the end of the lance is heated to 1350-1400s with the help of an acetylene-oxygen flame of a welding torch, which is also used when re-energizing the cutting process after it has been pre-curved. In the proposed method, at the beginning of the cutting and after the breaks, the spear is heated mainly by immersion. To a depth of 300 mm in liquid aly. AL-27 mini-alloy (88-90.5% aluminum, 9.5- 11.5% magnesium and 0.050, 15% titanium), overheated in an electric furnace under surface slag (sodium, potassium and magnesium chlorides) up to 950-1000 ° . If necessary, to prevent oxidation of the alloy at the end of the lance in air or for its cooling, an additional short-term heating is carried out with a reducing burner flame. In addition, in the beginning of the cutting, as well as upon detection of signs of attenuation into the depth of the cut, small portions of 50-100 g of the liquid alloy are taken, taken directly from the furnace for every 100 g of alloy adhered to the surface of the lance or introduced into the cut at 1400 kcal of additional heat is generated by interaction with oxygen, which represents a significant share in the total heat balance of cutting. Test data are shown in the table. As can be seen from the table, the proposed method has the best technical and economic characteristics. Using the proposed method of powder-and-spear cutting of metallic and non-metallic materials will reduce the temperature barrier, increase stability and reduce the unproductive costs of cutting time, increase the amount of heat input from the outside and heat generated during the process, and, consequently, increase productivity and cutting quality into the material being cut and reduce the specific consumption of materials, including scarce and expensive aluminum and iron shkov.

The heating temperature of the end of the lance is necessary to excite the cutting,

Warm-up time of the end of the lance at a length of 300 mm at the beginning of cutting, sec.

The time required to re-excite cutting at breakage, s

-h

Additional heat generation:

a / when burning 100 mg tube length lance, kcal

b7 with the introduction of 100 g of liquid alloy in a cut, kcal; Average cutting performance:

a / linear steel cutting ,. I mm / min

b / burning holes F 50 in a concrete slab, mm for

Material consumption: a / acetylene, b / oxygen, m / min w / flux, g / min

including aluminum powder, g / min

g / tube Lance / 17/8 mm, in m / min

900-1000

50-80

30-40

295

1390

305

min

115

14

0.95 120

9.6 0.6

Claims (2)

Invention Formula A method of powder-and-spear cutting (metallic and non-metallic materials, in which the end of the tube is heated to its oxygenation temperature and oxygen-flux cutting mixture is fed through the tube, characterized in that, in order to increase productivity by reducing the start time of the process, heating the end the tubes were made by immersion in a molten alloy based on gshyumini doped with magnesium and titanium, heated above the temperature at which the alloy began to burn in oxygen, but below its temperature of ignition in air. 2, Population Method 1, distinguished by the fact that, in order to prevent a decrease in the intensity of the cut during the process of cutting materials, the cut area introduces portions of the above alloy. Sources of information taken into account in the examination of 1 PRTPPTI r tt p „A U t. 1. Petrov G.L., Burov N.G. and Abramovich V.R. Technologists and equipment for gas processing of metals l Mechanical Engineering, 1978, p.229. 2. Spector O.Sh. Oxygen-flux cutting stainless steels M Mechanical Engineering G19b2, 119-126.