CN110539123A - Open arc online surfacing repair device and method for medium-speed grinding disc - Google Patents

Abstract

An open arc on-line surfacing repair device and method for a grinding disc of a medium-speed mill are disclosed. A welding gun is arranged above the disc surface of the grinding disc, the rear end of the welding gun is sequentially communicated with the dual-drive wire feeder and the welding wire straightening mechanism through a connecting rod, and a welding wire placed on the wire feeder penetrates into a wire inlet of the welding wire straightening mechanism; the dual-drive wire feeder is arranged on the welding trolley through the welding gun angle adjusting mechanism; a touch rod is arranged at the outer edge of the grinding disc and is matched with a position of a limit switch arranged on the wall of the coal bunker, and a cooling water pipe is respectively communicated with an inlet and an outlet of the welding gun and the circulating water tank to form a closed loop; the invention carries out on-line surfacing repair on the grinding disc under the condition of not dismantling the grinding disc, can save a large amount of manpower and material resources and shorten the overhaul period. The method mainly ensures that all properties of the surfacing layer meet the repair requirements through selection of welding parameters and welding modes.

Description

Open arc online surfacing repair device and method for medium-speed grinding disc

Technical Field

the invention belongs to the field of surfacing devices, and particularly relates to an open arc online surfacing repair device and method for a medium-speed grinding disc.

Background

The medium-speed grinding disc (hereinafter referred to as grinding disc) drives the grinding roller to grind raw coal falling from the central coal dropping pipe in production. The millstone runs at a higher temperature, and bears a larger grinding pressure and a larger impact force caused by raw coal, and the effective grinding area of the millstone is reduced along with the continuous impact and abrasion of raw materials to the millstone, so that wavy lines are formed, and the equipment efficiency is sharply reduced. When the grinding disc is worn to a scrapped size, only a new grinding disc can be replaced. The grinding disc is generally made of high-chromium wear-resistant steel and high-chromium cast iron materials, so that the grinding disc has good wear resistance, but is expensive to manufacture, complex in replacement procedure, long in period and high in cost.

Disclosure of Invention

The invention provides an open arc on-line surfacing repair device and method for a grinding disc of a medium-speed mill, which ensure that the open arc on-line surfacing grinding disc can be continuously operated, shorten the maintenance period and save a large amount of manpower and material resources.

The technical scheme adopted by the invention is as follows:

An open arc online surfacing repair device of a medium-speed grinding disc comprises a PLC welding control box, wherein a disc driving device is installed at the bottom of the disc, a welding gun is arranged above the disc surface of the disc, the rear end of the welding gun is sequentially communicated with a dual-drive wire feeder and a welding wire straightening mechanism through a connecting rod, and a welding wire placed on the wire feeder penetrates into a wire inlet of the welding wire straightening mechanism; the dual-drive wire feeder is arranged on the welding trolley through the welding gun angle adjusting mechanism; a touch rod is arranged at the outer edge of the grinding disc and is matched with a position of a limit switch arranged on the wall of the coal bunker, and a cooling water pipe is respectively communicated with an inlet and an outlet of the welding gun and the circulating water tank to form a closed loop; the electric welding machine and the welding trolley, the dual-drive wire feeder and the limit switch are connected with the PLC welding control box through corresponding control wires.

The grinding disc driving device comprises an I-shaped flange, one end of the I-shaped flange is connected with a main shaft of a medium-speed grinding motor to connect the grinding disc into a whole, the other end of the I-shaped flange is connected with a speed reducer after being connected with a universal coupling, the speed reducer is connected with a driving motor, and the speed reducer is connected with a grinding disc driving control box through a control line.

The wire feeding device comprises a wire feeding disc, the wire feeding disc is installed on an outer ring of the self-aligning roller bearing, and the self-aligning roller bearing is installed on a shaft fixed on the base.

Including the wind package, be equipped with a plurality of joints on this wind package, be equipped with the choke valve on a plurality of these joints, connect and tuber pipe intercommunication, the tuber pipe other end is fixed to the side of waiting to build-up welding mill welding bead.

An open arc on-line surfacing repair method for a grinding disc of a medium-speed mill mainly comprises the following steps:

1) Adjusting a water-cooled welding gun to a position to be welded, wherein the included angle between the welding gun head and the grinding disc in the vertical direction is 5-10 degrees, and the dry elongation of the welding wire is 20-30 mm;

2) The welding parameters are controlled as follows: the driving rotation parameter of the grinding disc is 21.0-25.5 r/min, the welding voltage is 30-32.5V, the welding current is 320-480A, and the wire feeding speed is 3.4-3.8 m/min;

3) Adopting a multi-layer and multi-welding-bead surfacing method, welding one pass and then welding the next pass, wherein the lapping amount of the welding passes is 40-60% until the whole surface of the grinding disc with the medium speed grinding is fully welded;

4) In the open arc surfacing process, an infrared temperature measuring gun is used for measuring the temperature between welding layers every 1-2 hours, and the temperature is not more than 120 ℃.

the invention adopts an open arc on-line surfacing repair method to weld and repair the millstone which is worn to a certain size. When repairing, only the on-line surfacing equipment and the welding wire are needed to be transported to a medium-speed grinding working site, the manhole door is opened, and the surfacing equipment is installed in the coal mill bin, so that the grinding disc is repaired by the wear-resistant flux-cored welding wire on line in the condition of not removing the grinding disc. Because the links of disassembling, hoisting and assembling the grinding disc do not exist in the whole online repairing process, a large amount of manpower and material resources can be saved, and the overhaul period is shortened.

The invention adopts the water cooling circulation system to ensure that the welding equipment stably operates; the grinding disc is easy to drive and install and controllable in frequency conversion by adopting a worm gear reducing motor for driving and a universal coupling; controlling the temperature between welding layers by adopting an air cooling system; the dual-drive wire feeding system is adopted to drive the wire feeding disc to rotate for wire feeding, so that the wire feeding is smooth and stable; and the wear resistance of the overlaying layer meets the repair requirement by adopting the wear-resistant flux-cored wire.

the open arc on-line surfacing grinding disc is a cold welding repair method, and the temperature between welding layers is strictly controlled in the whole surfacing process. The coal pulverizer inner space is narrow and small, and welding temperature rises very fast, when actual build-up welding, through using compressed air to carry out the blast cooling to the build-up welding layer to guarantee that welding interlayer temperature satisfies technical requirement.

The power supply of the on-line surfacing equipment adopts a Radi inverter power supply, the machine has the characteristics of constant voltage, constant current, steep drop and the like, and is multipurpose, efficient, energy-saving and suitable for continuous surfacing welding. The dual-drive wire feeder adopts a four-wheel direct-current wire feeding mode, the speed is continuously adjustable, the output current of the welding machine is directly controlled, the welding forming is good, and the wire feeding is stable. The welding gun adopts a special water-cooling welding gun, and the welding gun is maintained at a lower temperature through circulating water cooling, so that the continuous and stable surfacing process is ensured. The millstone is driven by a 4KW worm turbine speed reducing motor, the transmission is universal joint transmission, the millstone is connected with the fan side of a motor of the mill and is connected with a main shaft of a motor of the medium-speed mill through a flange, the speed regulating part adopts frequency conversion speed regulation, and the rotating speed is stepless and adjustable.

The configurations ensure that the open arc on-line surfacing grinding disc can carry out continuous operation, shorten the overhaul period, and have attractive weld bead forming, stable welding performance and better popularization and application values.

The following are the effects of the present invention that appear after 2 years of practical use:

1. The equipment runs smoothly, the working efficiency is high, and the abrasive disc surfacing welding quality is excellent. And the increase of the sales income by 450 ten thousand yuan is realized in 2018, and the increase of the sales income by 446 ten thousand yuan is realized in 2019.

2. And the overhaul period is shortened: the open arc on-line surfacing medium-speed grinding disc can save links of disassembling, hoisting and assembling the grinding disc in the conventional off-line repairing process, shorten the maintenance period and save the cost. The off-line repair of the grinding disc of the medium-speed mill comprises five steps, namely, the grinding roller is disassembled (the grinding disc can be disassembled after the grinding roller is disassembled), the grinding disc is disassembled, the off-line surfacing grinding disc, the grinding disc is assembled and the grinding roller is assembled, the construction period is 12-15 days, the on-line surfacing of the grinding disc of the medium-speed mill is only 2 days, and the maintenance period of the medium-speed mill is also guaranteed.

Drawings

Fig. 1 is a schematic view of the overall structure of the present invention.

in the figure, 1, a grinding disc; 2. a conductive nozzle; 3. a welding gun; 4. a cooling water pipe; 5. a connecting rod; 6. a welding gun angle adjusting mechanism; 7. a Y-axis (vertical) walking track; 8. welding a trolley; 9. a dual drive wire feeder (Z5D 150); 10. a welding wire straightening mechanism; 11. a traveling track rib plate; 12. the inner wall of the coal mill; 13. an X-axis (transverse) traveling rail; 14. a wire feed hose; 15. welding a trolley control line; 16. controlling a wire of the dual-drive wire feeder; 17. a limit switch; 18. a touch rod is touched; 19. a welding wire barrel; 20. a wire feeding disc; 21. a self-aligning roller bearing (22220 CA/W33); 22. a shaft; 23. a base; 24. a PLC welding control box (CG-1000 AKZX); 25. a control line of the electric welding machine; 26. electric welding machines (MZ-1000 CV); 27. a limit switch control line; 28. a remote controller control line; 29. a remote controller; 30. a circulating water tank; 31. a grinding disc drive control box (CG-MPKZX 7.5); 32. a millstone drive control line; 33. a millstone drive motor; 34. a worm gear reducer; 35. wind bags; 36. a joint; 37. a throttle valve; 38. an air duct; 39. a universal coupling; 40. an I-shaped flange; 41. and (5) grinding the motor spindle at a medium speed.

Detailed Description

The present invention and its effects will be further explained below with reference to the accompanying drawings.

Referring to fig. 1, the open arc online surfacing repair device of the medium-speed grinding disc comprises a PLC (programmable logic controller) welding control box, wherein a disc driving device is installed at the bottom of the disc 1, a welding gun 3 is arranged above the disc surface of the disc 1, the rear end of the welding gun 3 is communicated with a wire outlet of a dual-drive wire feeder 9 through a connecting pipe 5, a wire inlet of the dual-drive wire feeder 9 is communicated with a wire outlet of a welding wire straightening mechanism, and a welding wire placed on the wire feeding device penetrates into a wire inlet of the welding wire straightening mechanism; the dual-drive wire feeder 9 is arranged on the welding trolley 8 through the welding gun angle adjusting mechanism 6; a touch rod 18 is arranged at the outer edge of the grinding disc 1, the touch rod 18 is matched with a limit switch 17 arranged on the wall of the coal bunker in position, and cooling water pipes are arranged on the periphery of the welding gun and are respectively communicated with an inlet and an outlet of the circulating water tank 30; the electric welding machine 26, the welding trolley 8, the dual-drive wire feeder 9 and the limit switch 17 are connected with the PLC welding control box through corresponding control lines.

The PLC welding control box is conventional equipment in the field, the model is CG-1000AKZX, the welding control part adopts the Chinese and English operation of a touch screen, and the control functions comprise: an X-axis welding stepping function; a Y-axis welding stepping function; an automatic start-stop function; the automatic gun falling and stopping and lifting functions of welding are realized; stopping welding and automatically winding wires; and a welding time recording function and the like, wherein the functions can be freely selected and switched according to the actual welding requirements, and parameters can be adjusted.

The welding wire straightening mechanism 10 is a device carried by a Z5D150 dual-drive wire feeder, and the welding gun angle adjusting mechanism 6 is a conventional device carried by a welding gun 3.

A pump is provided in the circulation tank 30.

the electric welding machine, the pump in the circulating water tank, the PLC welding control box and the millstone driving control box are all powered by a Rabdosia Rubescens inverter power supply.

the grinding disc driving device comprises an I-shaped flange 40, one end of the I-shaped flange 40 is connected with a main shaft of a medium-speed grinding motor to connect the grinding disc into a whole, the other end of the I-shaped flange is connected with a speed reducer 34 after being connected with a universal coupling 39, the speed reducer 34 is connected with a driving motor 33, and the speed reducer 34 is connected with a grinding disc driving control box 31 through a grinding disc driving control line 32. The grinding disc driving control box 31 is an existing device, adopts a model of CG-MPKZX7.5, and has two main functions, namely adjusting the rotation direction (clockwise rotation and anticlockwise rotation) of the grinding disc, adjusting the rotation speed of the grinding disc and realizing stepless adjustment of the rotation speed.

The wire feeder includes a wire feed disc 20, the wire feed disc 20 being mounted to an outer ring of a self-aligning roller bearing 21, the self-aligning roller bearing 21 being mounted to a shaft 22 fixed to a base 23.

the shaft 22 is firstly installed on the base 23, the self-aligning roller bearing 22220CA/W33 is installed on the shaft, and finally the whole wire feeding disc 20 is installed on the outer ring of the self-aligning roller bearing. When the welding wire straightening device works, the welding wire barrel 19 is placed on the wire feeding disc, the wear-resistant flux-cored welding wire penetrates through the welding wire straightening mechanism, the dual-drive wire feeder, the water-cooled welding gun and the conductive nozzle, and the welding wire exposed outside is protected by the wire feeding hose to prevent short circuit. When the dual-drive wire feeder pulls the welding wire to advance, the welding wire barrel rotates on the wire feeding disc, so that torsion of the welding wire in the barreling process is offset, the welding wire is prevented from rotating in the surfacing process, the surfacing quality is improved, and the consumption of accessories such as a water-cooling welding gun and a conductive nozzle can be reduced.

the invention also comprises an air cooling system which comprises an air bag 35, wherein a plurality of joints 36 are arranged on the air bag 35, a plurality of throttle valves 37 are arranged on the joints 36, the joints 36 are communicated with an air pipe 38, and the other end of the air pipe 38 is fixed on the side of the grinding disc weld bead to be built-up welded. The wind packet 35 is a self-made diversion container into which compressed air is introduced at the customer site.

The welding wire exposed to the outside is protected by the wire feed hose 14 against short circuits.

The welding PLC control box is provided with a remote controller 29, so that the operation and the control are convenient.

The mounting method of the open arc on-line surfacing repair device of the medium-speed grinding disc comprises the following steps:

1. Jacking a hydraulic cylinder of the medium-speed coal mill to separate the grinding disc from the grinding roller and enable the grinding disc to rotate;

2. Cleaning sundries such as coal dust, coal gangue and the like on the surface of the grinding disc and in the coal mill bin;

3. The walking rails are installed, the X-axis (transverse) walking rails are welded and fixed on the inner wall of the coal mill bin, the rib plates are welded, the welding trolley is installed on the X axis in parallel, and the Y-axis (vertical) walking rails are installed on the welding trolley vertically, so that the welding trolley can be controlled to move up and down, left and right.

4. Installing a wire feeding system, installing a dual-drive wire feeder provided with a welding wire straightening mechanism on a welding gun angle adjusting mechanism, and installing the welding gun angle adjusting mechanism on a Y axis so as to enable the whole wire feeding system to be of an integrated structure.

5. installing a welding gun, installing a connecting rod on the dual-drive wire feeder in a threaded connection mode, installing a water-cooling welding gun on the connecting rod, installing a conductive nozzle at the end part of the water-cooling welding gun, and connecting the water-cooling welding gun with a circulating water tank by using a cooling water pipe.

6. The grinding disc driving device is installed, firstly, the I-shaped flange is fixed on a main shaft of a medium-speed grinding motor through bolts, then, the universal coupling on the original grinding disc drive is connected with the fixed I-shaped flange through the bolts, and finally, the bottom of the grinding disc drive is welded and fixed through angle steel, so that the grinding disc can be driven to rotate through the grinding disc drive.

7. The limit switch 17 is fixed on the inner wall of the coal mill, the touch rod 18 is welded and fixed at the edge part of the grinding disc, and when the grinding disc driving motor drives the grinding disc to rotate, the touch rod can trigger the limit switch.

8. On connecting the control line, will weld dolly, dual drive send a control line of machine, remote controller, limit switch, electric welding to be connected to PLC welding control box respectively, the welding control part adopts touch-sensitive screen chinese and english operation, and control function includes: an X-axis welding stepping function; a Y-axis welding stepping function; an automatic start-stop function; the automatic gun falling and stopping and lifting functions of welding are realized; stopping welding and automatically winding wires; a welding time recording function and the like, wherein the functions can be freely selected and switched according to actual welding requirements, and parameters can be adjusted; the grinding disc drive control line is connected to the grinding disc drive control box, and the control part adopts variable frequency speed regulation control and stepless regulation of the rotating speed.

9. and (3) assembling the wire feeding disc, fixing the shaft to the base, installing the self-aligning roller bearing 22220CA/W33 on the shaft, and finally installing the whole wire feeding disc on the outer ring of the self-aligning roller bearing. When the welding wire straightening device works, a welding wire barrel is placed on a wire feeding disc, the wear-resistant flux-cored welding wire penetrates through the welding wire straightening mechanism, the dual-drive wire feeder, the water-cooled welding gun and the conductive nozzle, and the welding wire exposed outside is protected by a wire feeding hose to prevent short circuit. When the dual-drive wire feeder pulls the welding wire to advance, the welding wire barrel rotates on the wire feeding disc, so that torsion of the welding wire in the barreling process is offset, the welding wire is prevented from rotating in the surfacing process, the surfacing quality is improved, and the consumption of accessories such as a water-cooling welding gun and a conductive nozzle can be reduced.

10. And installing an air cooling system, introducing compressed air on the site of a user into an air bag (a self-made flow distribution container with a plurality of joints), and finally fixing a plurality of air pipes to the side of the grinding disc weld bead to be built up.

11. After the grinding disc rotates normally, an automatic welding button on the PLC welding control box is pressed, and when the grinding disc rotates to touch a limit switch, welding is started.

12. And after the grinding disc subjected to online surfacing meets the repair requirement, moving out all the welding equipment, the air pipe, the control line and other articles in the coal mill bin, and sealing the manhole door.

An open arc on-line surfacing repair method for a grinding disc of a medium-speed mill mainly comprises the following steps:

1) Adjusting a water-cooled welding gun to a position to be welded, wherein the included angle between the welding gun head and the grinding disc in the vertical direction is 5-10 degrees, and the dry elongation of the welding wire is 20-30 mm; the length of the electric arc can be kept in a moderate state during surfacing by adjusting the parameters, and the overflow of a welding pool is avoided.

2) the power of equipment such as pump, PLC welding control box, mill drive control box in electric welding machine, the circulation tank is started, after opening air cooling system, welding parameter control is: the driving rotation parameter of the grinding disc is 21.0-25.5 r/min, the welding voltage is 30-32.5V, the welding current is 320-480A, and the wire feeding speed is 3.4-3.8 m/min; by the aid of the parameter surfacing millstone, current and voltage are appropriate, the thickness of a welding layer is 2-3mm, a welding bead is flat, and splashing is little.

3) adopting a multi-layer and multi-welding-bead surfacing method, welding one pass and then welding the next pass, wherein the lapping amount of the welding passes is 40-60% until the whole surface of the grinding disc with the medium speed grinding is fully welded; and after the first layer is fully welded, the next layer is welded, and the welding is repeated until the size of the abrasive disc after overlaying meets the repair requirement. The welding lap amount is 40-60%, and the surfacing layer is relatively flat.

4) In the open arc surfacing process, an infrared temperature measuring gun is used for measuring the temperature between welding layers every 1-2 hours, and the temperature is not more than 120 ℃. The grinding disc is made of high-chromium cast iron, the grinding disc can be cracked due to overhigh temperature, and the interlayer temperature is controlled by adopting a high-pressure air cooling mode in the surfacing process and generally does not exceed 120 ℃.

Claims (7)

1. an open arc online surfacing repair device of a medium-speed grinding disc comprises a PLC (programmable logic controller) welding control box and is characterized in that a disc driving device is installed at the bottom of a disc (1), a welding gun (3) is arranged above the disc surface of the disc, the rear end of the welding gun (3) is sequentially communicated with a dual-drive wire feeder (9) and a welding wire straightening mechanism (10) through a connecting rod (5), and a welding wire placed on the wire feeder penetrates into a wire inlet of the welding wire straightening mechanism (10); the dual-drive wire feeder (9) is arranged on the welding trolley (8) through the welding gun angle adjusting mechanism (6); a touch rod (18) is arranged at the outer edge of the grinding disc (1), the touch rod (18) is matched with a limit switch (17) arranged on the wall of the coal bunker in position, and a cooling water pipe (4) is respectively communicated with an inlet and an outlet of the welding gun and a circulating water tank (30) to form a closed loop; the electric welding machine (26) and the welding trolley (8), the dual-drive wire feeder (9) and the limit switch (17) are connected with the PLC welding control box through corresponding control wires.

2. The open arc on-line surfacing repair device for the medium-speed grinding disc according to claim 1 is characterized in that the grinding disc driving device comprises an I-shaped flange (40), one end of the I-shaped flange (40) is connected with a main shaft of a medium-speed grinding motor to connect the grinding disc into a whole, the other end of the I-shaped flange is connected with a universal coupling (39) and then connected with a speed reducer (34), the speed reducer (34) is connected with the driving motor, and the speed reducer (34) is connected with a grinding disc driving control box through a control line.

3. The open arc on-line surfacing repair device for the grinding disc of the medium-speed mill according to claim 1, wherein the wire feeding device comprises a wire feeding disc (20), the wire feeding disc (20) is mounted on an outer ring of a self-aligning roller bearing (21), and the self-aligning roller bearing (21) is mounted on a shaft (22) fixed on a base (23).

4. The open arc online surfacing repair device for the medium-speed grinding disc according to claim 1 is characterized by comprising an air bag (35), wherein a plurality of joints (36) are arranged on the air bag (35), a throttle valve (37) is arranged on the plurality of joints (36), the joints (36) are communicated with an air pipe (38), and the other end of the air pipe (38) is fixed to the side of a weld bead of the grinding disc to be surfaced.

5. The open arc on-line overlaying repair device for the medium-speed grinding disc according to claim 1, wherein welding wires exposed outside are protected by a wire feeding hose (14).

6. Open arc on-line surfacing repair device for medium speed grinding discs according to any one of claims 1 to 5, characterized in that the PLC welding control box is provided with a remote controller (29).

7. An open arc on-line surfacing repair method for a grinding disc of a medium-speed mill is characterized by mainly comprising the following steps:

1) Adjusting a water-cooled welding gun to a position to be welded, wherein the included angle between the welding gun head and the grinding disc in the vertical direction is 5-10 degrees, and the dry elongation of the welding wire is 20-30 mm;

2) The welding parameters are controlled as follows: the driving rotation parameter of the grinding disc is 21.0-25.5 r/min, the welding voltage is 30-32.5V, the welding current is 320-480A, and the wire feeding speed is 3.4-3.8 m/min;

3) adopting a multi-layer and multi-welding-bead surfacing method, welding one pass and then welding the next pass, wherein the lapping amount of the welding passes is 40-60% until the whole surface of the grinding disc with the medium speed grinding is fully welded;

4) In the open arc surfacing process, an infrared temperature measuring gun is used for measuring the temperature between welding layers every 1-2 hours, and the temperature is not more than 120 ℃.