With the rapid development of sheet metal processing technology, the gap between domestic and foreign processing technology is getting smaller and smaller.Many well-known foreign companies have moved their production bases to China.At the same time, it also brings a lot of reactionary ideas to sheet metal processing.
Laser cutting is the technical response of sheet metal processing and the "processing center" of sheet metal processing.High flexibility, fast cutting speed, high consumption efficiency, product consumption cycle is short, laser cutting has won a broad market for customers.
Laser cutting has no cutting force and no machining deformation;No tool wear, good data compliance;No matter the simple part or the complex part, it can be formed accurately and rapidly with laser once.Its cutting weld is narrow, cutting quality is good, automation level is high, operation is simple, labor intensity is low, pollution-free, can complete automatic cutting layout, layout, improve data utilization rate and consumption cost, economic benefit is good.
The technology has a long useful life.At present, most of the foreign thickness in the 2mm above the plate are cut with laser.Many foreign experts believe that the next 30-40 years will be the golden age of laser processing technology.
Laser cutting machine is more and more widely used, more and more materials are used.However, different materials have different characteristics, so the problems that need to be paid attention to in the use process are also different.Laser cutting machine.The following is a brief analysis of the main materials.
Good results will be obtained when the material is cut with oxygen.When oxygen is used as a processing gas, the blade is slightly oxidized.Nitrogen can be used for cutting sheets up to 4mm thick.
Oxygen is needed when cutting stainless steel.When the edge oxidation is not important, nitrogen is used to obtain the edge without oxidation and burr, and no additional treatment is required.
Aluminium with a thickness of less than 6mm can be cut according to the type of alloy and the performance of the laser, despite its high reflectivity and thermal conductivity.
Argon and nitrogen were used as processing gases to cut the titanium plates.Synthetic materials
All organic cutting has a risk of fire (nitrogen can be used as a processing gas, compressed air can also be used as a processing gas).Wood, leather, cardboard and paper can be laser-cut, but the blade will be burned.
In laser cutting machines, it is necessary to understand and process several core technologies for high-precision and large-thickness parts.The focus position adjustment is only the first in the table.The first advantage of laser machining is the high power density of the light, so the focal point is as small as possible, which facilitates the formation of a narrow slit.
Because the deeper the focusing lens is, the smaller the focal diameter is.For high quality laser cutting, reasonable relative aperture is also related to lens diameter and cutting material.Therefore, the focus of operation depends on where the material surface is cut off.
Since the load of the particle beam has a great influence on the laser cutting speed, the focal length of the lens is a key problem.The size of the spot is positively correlated with the focal length of the lens.The focal spot size of the lens with short focal length is small and the light load at the focal point is very large, which is very beneficial to laser cutting of materials.
However, its disadvantages are relatively short aperture and small adjustment capacity, which is generally more suitable for high-speed laser cutting thin materials.Since fixed focal length lens has a wide focal depth, it is more suitable for laser cutting thick workpiece if there is sufficient power density
After the clear application of several focal length lenses, the focus and position of steel surface layer are of great significance to ensure the quality of laser cutting.Due to the high power density of the focusing portion, in most cases the focusing portion is located only at or just below the surface of the steel sheet during laser cutting.
In the whole laser cutting process, ensuring the constant position of focus and steel parts is the key to achieve the laser cutting quality balance.Sometimes, due to improper cooling, the lens encounters heat, which causes a change in focal length.Therefore, the focus must be adjusted immediately.
When the focus is in the right place, the slit is smaller and more efficient.Laser cutting laser cutting speed can get better laser cutting effect.In most applications, the light focus is adjusted below the nozzle.The distance between the nozzle and the steel surface is usually 1.6mm.
In the application of particle beam, self-focusing problems are often encountered.There are a few simple operations to determine the focus position:
(1) Copying method: make the laser cutting head run from top to bottom, and print the particle beam on the plastic plate.The smaller the printing diameter is important.
(2) Oblique column method: The plastic plate is placed on the side with the same Angle of view as the vertical axis to drive the focus of the smaller points of the parallel beam.
(3) Blue flame method: remove the nozzle, blow the air, hit the pulse lamp on the stainless steel plate, make the laser cutting head move from top to bottom, until the blue flame focuses on a large place.