Currently, there are different types of downstream processing equipment in the corrugated box industry. There are basically four methods. The first is the chain type single machine printing. This kind of equipment uses the chain to send the cardboard directly to the printing. After printing, it can be cut, indented, not grooved and afterwards, but also depends on the stand-alone machine to continue the processing. It only plays the role of printing. A relatively simple printing equipment. The second is the use of vacuum adsorption or scraper-type printing slot printing or circular press die cutting, automatic palletizing equipment, is a more common printing slotting machine. This type of equipment is printed on the above type and can be formed by artificial nailing or bonding after processing. The third is vacuum adsorption printing, circular die-cutting, chip removal equipment, suitable for manufacturing high-end sales packaging, is currently more advanced printing equipment. Then there is the automatic molding machine, also known as the joint motivation. This equipment includes vacuum feeding, printing slotting, folding and bonding (stamp box), packing and other processes. This type of equipment uses the following type of ink for bonding or nail box. It saves time and labor by one-step forming and should be promoted. use. It is a typical post-processing equipment for corrugated cartons. It includes almost all the quality problems that often occur in subsequent processes. Prior to this, the author has elaborated on the problems that have arisen in the printing industry. This article only analyzes the manufacturing processes and prone problems of the main processes except for printing, and proposes corresponding solutions.
Corrugated box printing slotting, folding and bonding machine process
(Making a flow chart) 1. Feeding - 2. Printing - 3. Slotting - 4. Die cutting - 5. Gluing - 6. Folding - 7. Nail bin - 8. Accumulation - —9. Packing
The manufacturing process of the automatic folding and bonding machine generally requires the above nine processes. It adopts adsorption type feeding, under ink printing, slotting automatic positioning, and can be glued and nailed at the same time after being glued and folded. It can be automatically counted, piled up, pushed out, directly put into the warehouse after packing, and carton forming can be completed at one time. In the production process, due to the influence and constraints of many factors, some quality problems will be generated to varying degrees. The following quality analysis will be carried out according to the production process sequence.
Analysis and Solution of Quality Problems in Automatic Corrugated Box Machine
● Feeding section
Due to improper adjustment, it was difficult to feed paper and jammed, resulting in inaccurate or damaged cardboard feeding.
Analysis of the reasons: Due to improper adjustment of the front and rear flaps of the cardboard feeding section, or warpage of the cardboard, the cardboard cannot smoothly enter the next process, causing quality problems.
Solution: First, adjust the distance and clearance of each baffle in the paper feeding section, especially the front and rear baffles. The front baffle should adjust the gap according to the thickness of the corrugated board. The basic gap should be greater than 1 board thickness and less than 2 board thicknesses to ensure that only one board can be passed at a time. The gap between the upper and lower ends of the paper feed roller must be parallel. If it is not uniform, the paper feed skew will occur. The gap should be slightly smaller than the thickness of one paperboard, but it should not be too low, otherwise it will cause the paperboard to be thin or corrugated. In order to overcome the paper-feeding difficulties caused by the warp of the board, it is necessary to raise the feed tray to a stand, so that a small piece of cardboard is stuck on the paper feed table so as to be replenished little by little when feeding. If scrapers are used, it should be noted that the stacking height of the cardboard on the feeding device is generally about 400 mm to 480 mm. If the cardboard code is flickering (cardboard storage more or less), it will affect the depth of the slot after feeding.
● slotting, pressure line section
The slot size is inaccurate, the depth is inconsistent, the knife edge is not clean, and the base knife guide plate wears and removes swarf. Improper adjustment of the concave cam gap of the pressure line, inconsistent creases, and fracture at the indentation.
Reason analysis: Due to the improper size setting of slotted and pressed wire, the size is not allowed; the width of the paperboard is too small or close to the minimum limit of the equipment; the groove depth is not accurate; the grooved knife is worn or the guide plate does not work, which causes the knife edge to be not clean. Debris removal difficulties; the pressure roller is not centered up and down, and the depth is not enough, there is a "snaking line" or breakage at the crease.
Solution: First, the size of slotted and pressed wire shall be determined according to the manufacturing dimensions designed by the process drawing, and the slotted knife and the knife seat shall be locked, and the mass production shall be carried out after the first item is checked and checked; if the paper board is too narrow, the various parts shall be transferred. Roller (also known as traction roller) is adjusted at the position of the pressure line, and the gap is slightly less than the thickness of a paperboard, but the transfer roller must play a role; the knife edge should be checked whether the upper and lower grooving knife is worn or not. Clearance, in this case will change the tool, remember to ensure that the knife is installed in pairs, so with a good match; check the guide plate is loose, if there is wear should be replaced; pressure line position must be in the middle of the slotting knife, this Is the actual size of the production, if there is still a cardboard breakage, we must consider whether the raw material quality problems, to ensure that the "pressure line centered, deep drum does not crack."
●Folding section
Folding is not correct, plugging; uneven glue adhesive, bonding is not strong.
Analysis of reason: Due to the looseness of the conveyor belt, chain, and push-pull module in the folded section, or the inconsistent left-right tension, the paper feed is skewed and jammed; the gap of the rubber pad or the viscosity of the adhesive is not enough, resulting in uneven coating and adhesion bad.
The solution: The folding part is a main process of the entire carton back-end processing. Its function is completed by the inverted belt, which is assisted by the escort bar. The escort rod is positioned on the diagonal roller wheel near the top and the belt is flipped over here so that bouncing and chattering can be avoided so as not to damage the cardboard. The cardboard is carried by the chain system through the folded gluing section. The sprocket is mounted on the inner side of the folding arm and the top block is mounted on the chain. They can precisely control the parallelism and verticality of the cardboard. In order to avoid skewing and jamming of the carton during the folding process, firstly adjust the tightness of the conveyor belt and the chain and the parallelism of the paper pushing module, and move the folding arm to a predetermined position. As the carton passes, the transfer guide on the folding track is fully pressed along the indentation, and the pressure of the transfer roller is adjusted according to the thickness of the board to ensure the normal operation of the board.
The problem of uneven sizing and poor adhesiveness is mainly due to insufficient glue supply and insufficient adhesive viscosity. Therefore, check whether there is enough glue in the groove of the support rubber wheel, and then check whether the return pump is damaged or blocked. . The adhesive can use polyvinyl acetate emulsion (ie, white latex) or adhesive with the same adhesive effect. The emulsion can be added with little water and it should not be diluted. The pressure of the rubber wheel should be appropriate, and the glue should be evenly coated on the connecting edge.
● Combined part
Poor adhesiveness, adhesive overflow of carton adhesion, inconsistent width of joints, upper and lower mouth is scissors; nail head and tail nail position and nail distance is not accurate, nail saw damage, corrosion, nails are not fixed, the mouth is uneven, the width is not uniform As well as broken nails.
Analysis of the causes: The quality problems caused by the combination of the parts are many, and the adhesive is mainly a problem with adhesives and folding processes. Nail bins are due to nail saws and machine adjustment issues. However, they all have common problems, such as inconsistencies in their counterparts and widths.
Solution: At present, there are three ways to combine: First, bonding, second, nailing, and third, glueing. The former two are used more often and the latter is less. However, the purpose of the integration is consistent, and they are all designed to bind the carton firmly together. If the above problems occur, it will directly affect the firmness of the carton.
For adhesive problems, the adhesive viscosity and coating uniformity are mainly considered. If the adhesive overflows and the carton sticks, the longitudinal movement of the glue part and the tire rubber is adjusted to the predetermined position.
The nail box problem must first check the hardness, thickness, bending of the flat wire for corrosion, cracking, etc. Currently used are copper-plated or galvanized flat yarns. Regardless of which flat yarn is used, the above problems are present to varying degrees, and if the above problems occur, it will directly affect the quality of the staples. Head and tail screws must be within 20 mm from the bottom line of the indentation as required by the standard and the saw should be stapled along the center of the lap tongue. The pitch is not uniform, and the speed of feeding the belt is adjusted because the speed of the belt is determined based on the relationship between the speed of the machine and the number of nails. When the single carton passes through the stapler, the speed of the box starts and ends. The speed is different. Therefore, after the box enters the nail box machine, the speed of the box is adjusted to the speed required for nailing, and the necessary adjustment data is input into the stapler, such as the first nail and the number of nails. When the cardboard thickness changes, the distance between the staple head and the lower nozzle must be adjusted. When bad filaments are produced or the flat yarn is not fed smoothly, check whether the filament path is smooth and whether the single, double prongs and square knives are sharp. When the nail saw is not working, it is necessary to check whether the nail is centered. It is necessary to ensure that the nail is adapted to the thickness of the carton so that no discs or cracks will occur.
● accumulation of parts
The carton count is inaccurate, there is a build-up of jams and difficulty in launching.
Analysis of the reason: Due to the incorrect timing of the counter and the ejector, the count is inaccurate. The pressure adjustment between the bottom feeder and the feed belt and the rollers was not proper, resulting in clogging and pushing difficulties.
Solution: The accumulation part consists of counting, stacking, and pushing. After the cartons are folded and nailed, the cartons are fed into the hoppers by the bottom stacking feeder. Then the number of cartons per bundle is selected. The cartons are ejected by the bundle ejector and the entire post process is completed.
In order to solve the problem of inaccurate quantity, we must first check whether the timing of the counter and ejector is accurate. The counter has a bundle counter, which is the total number of bundles that record the eject. Then there is the box number selector, which is the number of boxes required to select each bundle. The ejector is a loop timing regulator whose process length can be adjusted according to the running time. If it is not a counting problem, it is necessary to check whether the carton is slipping, skewed or out of sync during folding. The adjustment of the bottom stacker feeder should be based on the principle of ensuring good feeding, so that the inclination is as small as possible. If the carton cannot enter the hopper properly, there is a possibility that the pressure between the roller and the belt is insufficient, or the carton may interfere with each other. In particular, counting and jamming problems tend to occur when the warp of the board is severe. In this case, the inclination of the feed guide is increased. This problem also exists when the carton is ejected, which indicates that the number of cartons in the hopper and the number of cartons per bundle have been improperly adjusted. To align the cardboard, the distance between the front pallet and the pusher should be a few millimeters smaller than the slot height. In order to ensure that the carton is in the correct position in the hopper to ensure proper discharge, the pressure on the two sides of the carton must be adjusted, that is, the staples and the glues located near the center of the carton. Depending on the size and form of the carton, it is determined that it is pressurized at one or two locations. If the carton has a vibration phenomenon in the hopper, it means that the tilt of the feeder is too large. In the case of difficulty in launching, we must first check the timing of the air pressure supply and the ejector to see if it is too slow. If the cartons are pushed too fast and the output of each bundle is skewed, check whether the feed path has Obstacles, and the roller stuck.
In summary, there are many problems in the processing of the following roads. The above lists only the general problems of certain equipment. There are many others that are not listed one by one. The above is for reference only. Enterprises should analyze and take countermeasures according to the problems that occur in actual production equipment. Regardless of any problems, we must accurately identify the causes of the problems and take timely measures. Some problems are not difficult to solve.
---Carton Technology
