Hydraulic supports are key equipment for fully mechanized mining working faces in coal mines. It plays important roles such as road support and working face support, and at the same time prevents coal lumps, gangue Stones fall onto the mining working face and scraper conveyor to ensure smooth mining. Provide security. The main part of the box structure is mainly composed of top Plate, main floor plate, reinforced plate, transverse floor plate, cover plate, ear plate, side sealing plate and other steel Plate parts are made of tailor-welded parts, and the part cutting technology plays an important role in production quality and efficiency. Rate and cost play a decisive role. Hydraulic support panels are mostly cut by flame cutting or plasma. Arc cutting, due to large deformation, poor cutting surface quality, and poor dimensional accuracy To meet process requirements and other reasons, most parts need to be Leveling, milling, rough and fine boring, drilling and other processes, there are many parts processing processes, It is difficult, costly and has a long manufacturing cycle. Laser cutting technology is developing rapidly, with an annual growth rate of 15% to 20%. degree of growth, gradually moving into various fields, and has received great recognition from various industries. focus on.
1 Principles of laser cutting technology
Laser cutting uses focused high power and high energy density
The laser beam irradiates the workpiece, causing the irradiated material to quickly melt, vaporize,
Ablate or reach the ignition point with the help of high-speed airflow coaxial with the beam
The molten material is blown away to form a slit to achieve the purpose of cutting parts. exciting
Light cutting mainly includes controlled fracture cutting, melting cutting, and oxygen-assisted melting cutting.
There are four common cutting methods: cutting and gasification cutting.
Compared with other lights, laser has high brightness, high directionality, high
Four characteristics: monochromaticity and high coherence. Therefore, laser cutting has
Good cutting quality, wide cutting range, small heat affected zone, fast cutting speed,
It has the advantages of narrow slit and high processing flexibility and has been widely used.
2 Application of laser cutting technology in hydraulic supports
(1) High cutting accuracy and small subsequent processing volume
Laser cutting is a method with power densities up to 106
~107 W/cm2
High energy density thermal processing method, the focused spot diameter is
Generally, it is 0.1~0.5 mm, so the laser cutting slit is narrow and the cutting slit is
The mouth is smooth and flat, without burrs, and the roughness is generally Ra12.5~25.
High precision, center hole spacing error is 0.1~0.4 mm, plate contour
The error is 0.1~0.5 mm, the positioning accuracy is 0.05 mm, and the repeatable positioning accuracy is
The precision is 0.02 mm, which basically reaches the accuracy of drilling, boring, milling, etc.
Accuracy requirements after rough machining. In recent years, hydraulic support manufacturers have
The design of main floor plates, floor plates, ear plates and other panels has been researched and implemented.
Laser cutting process, some panels have eliminated drilling, boring, milling, etc.
Processing process, laser cutting of some parts is the last process, no
Re-machining and direct assembly and welding shorten the manufacturing cycle of the hydraulic support.
period, reducing manufacturing costs.
(2) The spacing between parts is small and the plate utilization rate is high
Before 2007, there was no laser cutting machine with 10,000-watt power in China.
Equipment, low power means that laser cutting has application limitations in thickness.
system. In recent years, 12 kW, 15 kW, 20 kW,
30 kW, 40 kW, 50 kW, 60 kW power laser cutting machines, this
Some 10,000-watt power laser cutting machines have been able to complete the processing of medium-thick hydraulic supports.
Cutting of plates (thickness t≤40 mm) gradually enters the application of hydraulic supports
field. At present, hydraulic support panels are cut by flame cutting and plasma arc.
There are 3 main cutting methods: cutting and laser cutting.
Laser cutting of plates of various thicknesses and spacing between parts
Both are smallest, compared with flame cutting and plasma arc cutting, a single steel plate
More plates can be produced, and the plate utilization rate is higher than that of flame cutting and etc.
Ion arc cutting is more than 3% higher. Statistics show that hydraulic supports
Medium-thick plates account for 62% of the total number of plates, and monthly cutting hydraulic support
50,000 tons of rack panels, all panels with a thickness of no more than 40 mm are used
For laser cutting, the average steel plate price is calculated at 5,000 yuan/t. For comparison,
Use flame cutting and plasma arc cutting to save steel plate costs every month
About 4.65 million yuan.
(3) Common-edge cutting technology is applicable to a wide range of panels
Traditional common-edge cutting means that when arranging board parts, they will have the same length.
Plates with the same degree, same angle, same slope or same curvature are arranged in
Together, when generating cutting instructions, the common values of the outer contours of these plates
The edge part is cut only once, reducing the number of perforations and cutting paths.
diameter, thereby saving costs and improving cutting efficiency. laser focused light
The spot diameter is small and the cutting slit is narrow, which can effectively cut various complex panels without
Only objects with the same length, same angle, same slope or the same
Regular curvature boards can be cut along the same edge, and irregular boards such as grooves can also be cut.
Common edge cutting of parts. Compared with flame cutting and plasma arc cutting, laser cutting
Cutting expands the application scope of common-edge cutting technology, regardless of whether the panel is
Equal length or straight, as long as there are overlapping contours, common edge cutting can be performed.
Laser cutting can be applied to C-type common edges, CCD-type common edges, and L-type
Various more complex common-edge cutting technologies such as common edges can also be used through several cutting techniques.
Cutting technology is combined to achieve only the outer contour of several or multiple panels.
“One size fits all” with one perforation, forming a steel plate after cutting except for the remaining 4
There is almost no waste except steel plate edge scrap, and the currently popular “zero waste”
“Material” cutting method. Thus, the cutting quality of the hydraulic support plate is not changed.
Under the premise of the quantity and the outline of the plate, the utilization rate of the plate can be maximized.
(4) The heat affected zone is small and the plate deformation is small.
Cutting methods that utilize chemical reaction energy, electrical energy and light energy are used in cutting
It is always accompanied by a thermal process and is generally called thermal cutting method. laser cutting,
Plasma arc cutting and flame cutting are both thermal cutting. During flame cutting
The panels receive the most heat and the least when laser cutting. Usually, materials
The more heat is absorbed, the wider the heat affected zone, which means
Cutting causes greater deformation of the material. Cutting in hydraulic support panels
During the process, in order to obtain small part deformation, it is necessary to try to reduce the thermal shadow.
The width of the sound zone. Laser cutting has a small heat affected zone and is very suitable for hydraulics
Cutting of thick plates in brackets.
Flame cutting or plasma arc cutting in cutting hydraulic supports slender
When working with plates, due to large deformation and severe vertical bending, reverse deformation and breakage are often used.
Open blanking, increase machining allowance, increase milling process, upwarping, mechanical straightening
Measures such as positive and flame correction have affected the manufacturing cycle and increased a large number of
Manufacturing costs. With laser cutting, there is no tool wear during the cutting process.
No cutting force acts on the plates, no extrusion deformation or thermal influence between the plates
The area is small and the deformation of the panels is small, which ensures the assembly and welding of the hydraulic support panels.
While maintaining consistency, it shortens the manufacturing cycle without increasing manufacturing costs.
(5) Fast cutting speed and high cutting efficiency
The cutting gap in the laser cutting area is narrow, and the heat capacity of the material in the cutting area is small.
The laser energy density and energy utilization rate are high, so the cutting speed is fast.
Laser cutting speed is related to cutting machine power, cutting gas and other factors.
At present, the most widely used hydraulic supports are 15 kW and 20 kW.
Laser cutting with O2 cutting gas.
In the cutting of medium and thick plates of hydraulic supports, laser cutting
The cutting speed is 4 to 5 times that of flame cutting, and there is no plasma arc cutting speed.
The speed is fast, but the equipment is stable during operation and the maintenance cost is low in the future.
and other advantages, gradually becoming the mainstream of medium and thick plates for hydraulic supports
Cutting methods are becoming more and more intelligent and production-line-oriented.
(6) Promote intelligent manufacturing
The laser machine tool CNC system is based on the Windows operating platform, including
32-bit microprocessor, Ethernet communication interface, open data, equipment mutual
Connected to each other, supporting data interaction and remote management and control. Before 2006
Various laser cutting units have been supplied to the market abroad, and there are
An unmanned cutting production line composed of 6 large-scale laser cutting machines
The production line runs in the factory. At present, my country’s application field of hydraulic supports is
Combine the intelligent cutting production line with laser cutting machine as the core and other
Individual production line central control systems, MES systems, etc. vertically, horizontally, end-to-end
End-to-end integration to achieve high-quality, efficient, low-consumption, clean and flexible production,
Thereby establishing a smart factory based on industrial big data and the Internet. exciting
Due to its advantages in various aspects, optical cutting technology has contributed to the development of smart factories.
Establish.
3 Conclusion
Laser cutting has outstanding advantages in all aspects. As the technology becomes more and more mature,
mature, it will be more and more widely used in the field of hydraulic supports and will provide enterprises with
Bring more considerable economic benefits. Therefore, the majority of enterprises must strengthen their efforts to
In-depth research and application of light cutting technology to maximize its
Actual role in promoting the rapid transformation and upgrading of my country’s coal machinery equipment manufacturing industry.
