SU927454A1 - Method of electric slag welding by meltable tip - Google Patents

Description

(54) ELECTROSLAG WELDING, MELTING

The invention relates to the welding industry, in particular in the case of electroslag welding of products with a flute die.

Known for cnoccj6 electroslag welding with a melt die, which means that main and additional filler tubes are fed through the channels of the melt die, and the end shcholos are fed continuously. After elimination of the hfotsess, the wires are supplied only along the main ones. channels. In this case, the current and the national welding are measured. After the melting die loses contact with the slag bath, the supply of additional 1 x wires begins, the supply of the main wires continues, and the switch for switching on the main and auxiliary wires can be a current relay. In this way, they try to reduce the amplitude of oscillation of the power introduced into the slag bath and to achieve a uniform weld width tl.

MUNDSTUM

However, the known method of ESW has a number of disadvantages. In order to carry out an ESW according to a known method, at least two wire feeders, primary and secondary, are needed (for welding large-sized products with the melting nozzles of 1FOWELS feed mechanisms, they must be twice as large together with the corresponding drives and control systems). it

10 greatly complicates the welding technique. In addition, intermittently stopping the supply of auxiliary FLOWS at the moment when the slag bath touches the melt mouthpiece, in a row of spu | as shown, leads to the welding of the ends of the auxiliary wires with the TOjpuoM mouthpiece, which makes it difficult to resume the supply of auxiliary wires to the slag

20 bath with the separation of the melt of the scent mouth. This leads to the appearance of local incomplete welds in the welded seam, disturbances in the stability of the welding process, and a decrease in its efficiency. The chain of the invention is to strengthen the equipment, ensuring the uniform width of the weld to improve the quality of the welded joint. This goal is achieved by the fact that, according to the proposed ESW method, a current from the voltage source is supplied to the slag bath located in the gap between the edges of the products being welded, the current between the melting mouthpiece and the product is measured, the reference signal of the optimal active power introduced into the slag bath, determined by the actual active power in the slag bath by multiplying the welding current by the voltage between the melting core and the end, compare the signals proportional to the reference and reacting active power and a power error signal, which, by changing the parameters of the welding mode, leads to zero, periodically changes the feed rate of all electrode wires to the slag bath at a frequency equal to the frequency of natural modulation of the welding current amplitude when the current amplitude decreases and the feed rate decreases with increasing current amplitude, thereby bringing the error signal between the reference and the actual active power slag bath to zero. The drawing shows foams an example of the implementation of the proposed method of ESW. The circuit contains a floating mouth 1; electrode wire 2; slag bath 3; weld 4; pita source 5; drive supply of the electrode wires 6; block of proportionality 7; signal amplifier 8; current transducer 9; voltage generator 10; measure active power 11; correction unit wire feed speed 12. The method of electroslag welding is carried out as follows. When the slag bath 3 is guided through the channels of the melting mandrel 1, it is fed to the slag bath. On the basis of the amplifier 6, a converter 8 transducer with a constant initial speed of z. Electrode wire 2 under the influence of current from power source 5 begins to melt in slag bath 3, as a result of which weld seam 4 is formed. Current transducer 9 through proportional factor block 7 and amplifier-8 acts on the supply drive of electrode wire 6; wire feed with frequency amplitude current modulation. Active power meter II receives information from current transducers 9 and voltages 10 on a slag bath. The signal from the output 11 of the real output real power is compared in the comparison node with the onqjHbiM signal proportional to the optimal power and the difference of these signals through the correction unit 12 acts with an appropriate sign on the initial speed V setting to us in the converter-amplifier unit 8 power in the slag bath to zero. The proposed ESW method allows refusing additional auxiliary supply mechanisms, i.e. restrict the equipment, completely eliminate the possibility of welding the ends of the electrode wires with the end of the melted mouthpiece, since electrode wires are fed into the slag bath continuously without interruption, to ensure uniform weld width, thereby improving the quality of the welded joint and, in general, the efficiency of the ESW process. The ESW method is carried out by welding melts. the mouthpiece of the details of die equipment. The dimensions of the seam are 8OO X 125 50 mm. The A645 apparatus is used as a welding head, six electrode 3 mm in diameter, power source Tr-p TSHS ZOOO / 1, welding current 1.5 - 3kA, voltage 48 - are supplied through a melting mouthpiece size 75Ox 15OOx 1O mm. 50 V. The energy parameters are recorded by type H 370 type recorders; serial blocks from the high-speed instrument H 338-4P are used as current and voltage transducers; type D 556 is used as an active power meter. Setting the initial speed and periodic change in the speed of transmission ovolok indications of m devices is performed manually. During the welding process, the expected stability of the power introduced into the welding gap and the uniformity of the penetration width over the weld cross section are achieved. According to preliminary calculations, the economic effect of using the present invention in the ESM with a melt die allows to reduce the cost of the weld by 2.2%. Invention of the method of electroslag welding using a mouthpiece, c. that a slag bath located in the gap between the edges of the products being welded is supplied with current from the voltage source, the welding current is measured, the voltage between the melting tip and the product is formed, and a reference signal of the optimal active power is introduced into the slag bath , determine the actual active power in the slag bath by multiplying the welding current by the voltage between the floating mouthpiece and the product, compare the signals proportional to the reference and actual active power, and extract the mismatch signal and change the welding mode parameters to | zero the error signal to zero, characterized in that, in order to improve the equipment and to achieve a uniform width of the weld, the welding mode parameters change to 1PRODUCTED by periodically changing the feed rate of all electrode wires simultaneously through the melt mouthpiece a slag bath with a frequency equal to the frequency of natural modulation of the amplitude of the welding current, increasing the feed rate of the fluorescent tube for reducing the current amplitude. Sources of information taken into account in the examination 1. USSR author's certificate number 45067O, cl. B 23 K 25 / OO, 02.01.73 (prototype).

Claims (1)

Claim The method of electroslag welding with a consumable mouthpiece, consisting in the fact that the current from the voltage source is supplied to the slag bath located in the gap between the edges of the products being welded, the welding current, the voltage between the melting mouthpiece and the product are measured, the reference signal of the optimal active power introduced into the slag bath is formed, the real active power released in a slag bath by multiplying the welding current by the voltage between the floating nozzle and the workpiece, signals proportional to the reference and real active power are compared, and a mismatch signal is extracted and changing the parameters of the welding mode to bring the error signal to 10 zero, characterized in that, in order to simplify the equipment and achieve a uniform width of the weld, changing the parameters of the welding mode is done by periodically 15 changing the feed speed of all electrode wires simultaneously through the melting mouthpiece into the slag bath with a frequency equal to the frequency of natural modulation of the amplitude of the welding current, 20 increasing the wire feed speed with decreasing current amplitude.