With the continuous development of the commodity economy, the application of packaging and decoration printing technology is more and more widely. Among them, the concave-convex embossing process is an important part of the packaging and decoration printing process, and it plays an important role in the decoration and processing of cartons and other products. Concavo-convex embossing, also known as embossing process, is a special process technology for the surface processing of printed products and paper containers. This process is to use the greater printing pressure of the relief printing machine to print the partial patterns or The text is rolled into three-dimensional graphics with obvious differences between bumps and projections, which makes the printed graphics more beautiful and artistically attractive, thereby improving the quality of the product. Therefore, a correct understanding of the concave and convex embossing process technology is very important for improving the grade and quality of packaging products and improving the added value of commodities.
1 Adaptability of concave and convex embossing process
Due to the continuous advancement of printing technology, the application of surface finishing technology for packaging and decoration printed products is trending towards diversification, art and serialization. The application of hot foiling, UV glazing (partial layout), laminating, die cutting and indentation can not fully reflect the artistic level of packaging and decoration products. However, after embossing some graphics of the printed products, the The visual effect of the printed matter is greatly enhanced. The general concave and convex embossed substrate is more suitable for coated paper, whiteboard paper, glass cardboard and special paper, etc., and the quantitative adaptation range is between 180 ~ 350g / m2. Embossing concave and convex graphics with thick paper is the basic condition for obtaining good relief process effect. If the texture of the material is soft and thin, due to the lack of stiffness on the paper, the embossed graphic relief is not good. However, if the paper and cardboard with a relatively fragile material texture are used to emboss the concave-convex graphics on the cardboard that is too thick, the paper surface may be easily broken. Therefore, choosing the right material is a crucial part in determining product quality. The area of ​​the concave-convex embossed layout should not be too large, nor too large, nor should it be embossed on the thin lines. Generally, the concave and convex embossing should be carried out on the prominent graphic images of the printed products, and the concave and convex can also be pressed on the partial UV and hot foil plates to highlight the design theme of the product.
2 Carefully made gravure is the key to improve the quality of the embossed product
The concave and convex embossed intaglio is a negative graphic, and is also the master of concave and convex embossing. It is generally made of copper plate, steel plate or zinc plate. The material density of copper and steel plates is high, with the characteristics of pressure resistance and wear resistance, but their production is more difficult and the cost is high, so it is only suitable for products with fine and complex graphics and large production quantities; and the zinc plate material is brittle , The material is cheap, suitable for products with simple graphics and small quantities. The thickness of the plate material is usually between 1.5 ~ 3.0mm, which can be used according to the thickness of the printed material. The graphic depth of the printing plate can be determined according to the characteristics of the printed product, the thickness of the material, the toughness and the degree of withstand pressure, so as not to crush the paper. The gravure is usually made into a negative graphic version by etching or engraving. The depth of the plate made by the etching process is consistent, but the outline is not obvious, the level is poor, and the plate mouth has rough defects, so it should also be trimmed by hand engraving to make the embossed plate form a structure with obvious levels and clear outlines. Engraving is a meticulous modeling work. Corresponding technical methods must be adopted according to the requirements of the graphics. If the picture pattern is round, the mouth should be trimmed into a circular edge; if it is text or line, it should be The mouth is trimmed with straight edges; if it is to emphasize the three-dimensional shape, sometimes the mouth is trimmed with a bevel. Using machine engraving or electronic engraving to make plates, the production efficiency and precision are high. The edges of the engraved plate and text have almost no slope, and the quality is relatively good. In the traditional embossing process, the control of the quality of gravure production is the key link of the quality of the embossing product. It is necessary to select the appropriate gravure production process according to the characteristics of the product to improve the product quality. [next]
3 Several production methods of letterpress
The traditional relief printing process uses gypsum material or polyvinyl chloride (PVC), which has now been eliminated. The current letterpress production process is the same as the gravure production method. The copper and zinc plates have the good characteristics of material texture, wear resistance, high compressive strength, and not easy to deform. They are processed by corrosion or engraving.
4 Control of concave and convex embossing operation technology and process technology
1) Check the plate quality
After making the concave and convex embossed plate, you should first check whether the layout structure is complete and the level is clear; the layout graphics and specifications are compatible with the printed graphics and specifications; if the layout has pits and burrs, it should be cleaned.
2) Reasonable selection of embossed embossing base
Because the pressure of the embossed plate is greater than the printing pressure of the color printing plate of the same area, if the plywood that is easily deformed by compression is used as the plate holder, the embossed plate and text can hardly achieve the ideal relief effect. Therefore, the concave and convex embossed bottom bracket should use metallic materials, such as magnetic plate, aluminum plate bottom bracket or electric heating plate and other materials with high compressive strength. Among them, the electric heating plate bottom support is heated by the use of a metal bottom plate to transfer heat to the printing plates and printed products, so that the imprinted concave and convex marks are not easy to deform, and the paper or cardboard is not easy to break. Therefore, the process of using the hot plate to perform concave and convex embossing is generally more suitable for high-end decorative printing products.
3) Concave and concave plate mounting technology
When installing the plate, the intaglio plate should be installed in the center of the plate table to ensure the stability and uniformity of the pressure, so that the outline of the concave and convex pattern remains clear. When sticking the plates, please pay attention to the position of the plate once and stick it firmly to prevent the printing plate from being moved in the middle of imprinting and causing quality problems. Therefore, the relief plate made of non-gypsum, after the intaglio is glued, can be used to fit the relief plate (the back side should be glued with double-sided tape first) and the outline of the intaglio graphic, and use a little glue at the appropriate positions on both edges. After that, the machine is driven to perform imprinting, so that the letterpress sticks to the imprinting plate accurately. In addition, if the electric heating plate is used as the bottom plate for the concave and convex graphic layout, the plate installation tool should not use wooden strips and wooden wedges to fill in and fasten the printing plate, so as to avoid shrinkage and deformation due to the heating of the wooden material, which will cause the printing plate to move or There is a loose version. Therefore, metal materials such as aluminum strips, air lead, and iron plate locks should be used for hot press mounting.
4) Pressure debugging
Pressure is an important part of quality control. After the concave-convex plate is installed accurately, the pressure of the machine should be adjusted. It should be noted that when adjusting the pressure: the pressure should not be carried out from heavy to light, and it should not be blindly pressed at once to avoid damage to the printing plate. Therefore, the principle of correct pressure adjustment is to proceed gradually from light to heavy, until the contour of the relief is clear, and the obvious relief is appropriate.
5) The concave and convex embossing and die cutting indentation or foil stamping are completed at one time
If the concave-convex embossed product contains die-cutting indentation or foil stamping process, the concave-convex embossing process and die-cutting indentation or foil stamping process can be carried out at the same time. The method is: after the die-cut plate and hot stamping plate are installed accurately , Stick the concave-convex impression plate to the base plate and the platen with double-sided adhesive respectively, and it is required to properly paste the pad with a certain thickness on the platen corresponding to the die-cut indentation plate or hot stamping plate, so that the pressure The printed sheets at the time of printing basically keep the same horizontal plane on the flat plate, which can better ensure the accuracy of concave and convex embossing, die-cutting indentation and hot stamping. This process also requires the gravure or relief plate sticking to the imprinted plate. The thin gauge plate material should be selected as far as possible to make the padding of the stamping iron plate corresponding to the die-cut indentation plate or hot stamping plate as thin as possible. Some are conducive to the solidity, uniformity and stability of the pressure.
6) Relationship between paper (board) fiber direction and layout registration
Because the transverse fiber paper (board) is most prone to change in elongation, which will cause inaccurate overprinting of the plate, so the concave and convex embossed products must not be on the horizontal paper surface. When designing the concave and convex embossed layout of the multi-imposition structure, the concave and convex The embossed layout is designed as close to the longitudinal paper edge and printing rule edge as possible to improve the accuracy of product overprinting.
7) Selection of embossing machine
Due to the high pressure required for concave-convex embossing, products with good levels can be pressed out. It is advisable to use special equipment for die-cutting and indentation with quartile or folio. This machine only has a simple transmission and embossing device, which is more convenient to use. The castings of each part of the machine are reinforced. The embossed plate is pulled by double-arm gears. The pressure can be adjusted by the eccentric sleeve, and a safety bar is provided to protect the safety during operation. In addition, for high-volume concave-convex embossed products, a high-speed, flattened or round-pressed structured relief printing machine with automatic paper feed function can also be used to emboss the concave and convex lines, but the lining should be removed, and The version pasted on the roller should be made of a plastic or resin version that is easy to bend. [next]
5 Problems that should be paid attention to during the production process of embossing
The uneven embossed products have a certain artistic effect, and the product quality is relatively high, but once the production process is not properly controlled and quality problems occur, the process value of the product will be greatly reduced. Therefore, the following issues should be noted in production.
1) Transparency and loosening of printed sheets
The semi-finished products after printing or glazing are prone to sticking defects after stacking. In order to prevent double-sheet or multiple-sheet failures and crush the embossed plate, when the embossing is performed, the paper should be stacked (each stack has a thickness of 2 ~ 3cm) Hold the two corners of the paper with both hands, press the thumb on the top of the paper stack, pinch the index finger and middle finger under the paper stack, squeeze and move the paper stack inward, so that there will be a certain gap between the printed sheets of the paper stack The gap can penetrate the air to make the paper stack transparent and loose. In addition, you should turn the four sides of the paper stack and force the paper stack to squeeze to one side by hand to form an obvious inclined shape, and then hit the edge of the paper stack to make the paper stack transparent and loose.
2) Care should be taken to clean up impurities on the uneven surface
During the imprinting process, the paper coating, paper powder and paper wool are easy to come off and stick to the gaps of the printing plate, thereby affecting the quality effect of the concave and convex imprinting graphics, so the production should be stopped in time to check the layout and clean the plate Impurities in the grain to ensure product quality.
3) Pay attention to check whether the printing plate is damaged
Due to the brittle texture of the gypsum relief, prolonged compression is prone to cracking damage, depression deformation and other phenomena, which makes the uneven pressure insufficient. Therefore, the quality of printing plates and imprints should be checked frequently during production, and the damage of printing plates and pressure variations should be corrected in time.
4) Pay attention to check the pressure variation
The plywood backing, the double-sided adhesive on the back of the embossed plate, and the liner layer are easy to shrink and deform after heavy pressing, so that the pressure on the embossed plate surface is reduced, which in turn affects the quality of the product. Therefore, it is necessary to pay attention to the pressure of the printed layout during the production process, especially the first few thousand prints, the pressure variation is more severe, and the frequency of inspection is higher. If you find that the pressure on the layout is reduced, you should use appropriate thickness of paper to patch and press. [next]
6 Analysis of some fault phenomena of concave and convex embossing
1) The contour of the relief is not clear
During plate-making, the gravure graphics and text are enlarged too much, and the gap between the relief pattern of the non-gypsum material and the non-gypsum material after closing is too large, making the contour of the relief edge unclear. In addition, the uneven thickness of the printed sheets, uneven pad pressure, wear and loose phenomenon of the machine stamping mechanism, double or multiple sheets in the paper, compression deformation of the plywood bottom support, pressure cracks on the edge of the gypsum plate, etc. It will cause the problem that the outline of the relief is not clear enough, and the three-dimensional perception of the picture and text is poor. Corresponding measures should be taken to correct and prevent it.
2) Overprint graphics and text are not allowed
When the printing sheet is not positioned correctly, the printed sheet is deformed, the embossed plate is not sticky and is simultaneously displaced during compression, the paper is not skewed in place, and the positioning of the machine is unstable, which is easy to cause The overprint of the concave-convex layout is not accurate, and should be carefully checked, analyzed and processed.
3) Crushing of the uneven paper surface
If the pressure is too heavy, the edge of the concave and convex graphic layout is too sharp, the metal intaglio graphic is not properly expanded, the paper is too dry and fragile, the machine precision is poor and the imprint appears to vibrate, and there is a deviation error in the concave and convex graphic layout. It is easy to crush the graphic paper and can take corresponding measures to deal with according to the existing problems.
High-altitude Operation Truck, Aerial work truck, Sky lift truck, Overhead working truck transport refers to the staff and equipment to the site to be used and air operations of special vehicles.
Through the big arm front bracket, can be quickly installed lifting device or platform, realize the material function such as lifting, lifting, and manned aerial work, at the same time to extension assignments device and a variety of work device quickly switch provides the interface.
3 d rotation lift
Design three-dimensional rotating lift device, already can keep by lifting material profile automatically, and can realize the lifting materials in space any height, any location and any direction adjustment request, sensitive speed control precision, micro performance is good, can meet the large underground structure in high altitude and ventilation pipe installation requirements.
classification
According to the form of its lifting mechanism, generally can be divided into the telescopic arm type (ZhiBeiShi), folding arm type (crank arm type), vertical lift and hybrid four basic forms, etc.
Shear fork
Shear fork overhead working truck aerial work special equipment is widely used. The mechanical structure of it, make the lifting platform lifting has high stability, wide operating platform and high bearing capacity, larger, and the area of aerial work for many people work at the same time. It makes the work high above the more efficient, safe and more security.
Telescopic jib
Telescopic boom type aerial work platform is in the service in various industries aerial work, equipment installation, maintenance and other mobility aerial work products. Telescopic boom type aerial work platform is mainly divided into ZhiBeiShi aerial work platform and arm type aerial work platform. More used in the shipyard and other highly demanding place, this kind of machine safety is good, easy to move, but the cost is very high.
The crank arm type
Crank arm type overhead working truck mobile convenience, crank arm structure is compact. The new type of high quality steel, high strength, light weight, direct access to the alternating current (ac) or the power to start the car itself, construction speed is quick, with a telescopic boom, workbench extension, as well as rise, still can rotate 360 degrees, the obstacles to reach the working position, is the ideal aerial work equipment.
The crank arm type aerial work platform
Set of cylinder type
Set of overhead working truck cylinder type is a multipurpose aerial work machinery, its function will be carrying workers and use of equipment platform to the specified height carries on the special engineering equipment of the air. This equipment is widely used in industrial workshop, tall hall, warehouse, station, the work high above the square, etc. The machine by the platform, telescopic oil cylinder, single or dual ladder ladder type type anti-rotating tank body, chassis, leg, wheel, etc. Have telescopic cylinder direct jack-up platform, when start the motor, driven by the motor gear pump oil, the oil valve and electromagnetic input channels with oil cylinder, telescopic cylinder is up one by one day, when the platform when the system pressure reaches the maximum height to reach the rated working pressure, at this time have the unloading overflow valve, oil pressure to keep work at constant pressure, after the stop check valve pressure maintaining, platform will stay in the largest working position, platform can be below the maximum height according to the height of the scene of the homework stay at any position.
Working device
Overhead working truck working device including the leg mechanism, the lifting mechanism, slewing mechanism, operation platform and leveling mechanism, etc.
(1) the leg mechanism
Currently use hydraulic leg more. Use of automobile engine out of power to drive the hydraulic pump, through the control valve hydraulic pump of hydraulic oil supply working cylinder of the hydraulic leg, leg is adjustable. On both sides of overhead working truck, general equipped with a joystick, can make the four hydraulic leg around alone extend or retract, so even on uneven or dumping ground, also can adjust the body to the level state, the safe operation.
The rise and fall of implementation work platform and transformer.
Vertical lift lifting mechanism according to the transmission mode can be divided into hydraulic drive and mechanical drive, according to its structure can be divided into crossover scissors and sleeve. Cross scissors according to cross to decorate, articulated into scissors in the shape of a connecting rod frame structure. When changing the Angle of the connecting rod cross the lifting movement. The change of the connecting rod cross Angle, through the hydraulic oil cylinder piston rod or wire rope for release. Telescopic girder, box-type or cylindrical, finished with a multi sleeve telescopic lifting movement, drive mode can use hydraulic transmission or wire rope pulley. The job of lifting mechanism of vertical lift height is limited, scope of work is lesser, but the work platform is bigger, and support and stability.
Telescopic crane lifting mechanism of movable arm type can be divided into type or ZhiBeiShi, folding arm type or crank arm type, mixing arm type, this is the mainstream form of lifting mechanism. Telescopic arm lifting mechanism by multiple class suits, scalable box arm, including basic arm and telescopic arm, telescopic boom section for a day or more, the internode is equipped with hydraulic cylinder. When the hydraulic cylinder is working, the arm driven by hydraulic cylinder piston rod can slide up and down the guide element, which changes the length of the boom. Folding arm lifting mechanism composed of multiple box arms folded, can be divided into the folding and folding, folding and unfolding of each knuckle arm performed by each internode of hydraulic cylinder. Can complete a certain height and scope of operation, the folding space under ground plane can be completed homework. Mixing arm lifting mechanism consists of folding arm and telescopic boom, combined with the advantages of both, to expand the height of the homework and amplitude, and have strong ability of the disabled.
(3) the slewing mechanism
Usually takes the rotary swing mechanism, and reversing the direction can undertake choosing according to the requirements of the job. With reduction effect is usually driven by hydraulic motor rotating mechanical rotary device. Slewing mechanism of rotary parts and operation platform are installed on the rotary bearing the turntable. Drive device is fixed on the turntable, its bottom is equipped with drive gear. Rotary bearing by inner gear ring of the turntable and connected to the frame fixed seat. When the driver turns, the gear and the fixed ring gear meshing, along the ring gear rolling gear, drive turntable rotation. Between the turntable and the fixed gear ring seat with a ball or roller, in order to reduce the frictional resistance of turntable. Slewing mechanism of mechanical transmission form can use worm worm gear, cycloidal or planetary gear transmission ways.
(4) the work platform and leveling mechanism
The end connection of lifting mechanism of operation platform, is used for basic building blocks for the manned or equipment. In order to ensure the safety work and prevent equipment operation personnel, on the structure and performance of the work platform put forward specific requirements. Such as platform barrier height, width, non-slip surface platform, platform of seat belts, and so on.
In order to make the work platform at the bottom of the plane is always in the process of operation level, the work high above the car is equipped with automatic leveling work platform level institutions, mainly mechanical, liquid machine combination, electrohydraulic combined three categories.
High-Altitude Operation Truck,Aerial Platform Truck,Aerial Working Platform Truck,High Up Truck
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