After many years of use, equipment will suffer from various types of failures due to natural wear and poor maintenance. If the equipment is not repaired and maintained in a timely manner, the equipment will become sick and operation will be aggravated. Affecting the printing quality will also aggravate the wear of the equipment and cause difficulties for future maintenance work. We advocate a complete overhaul of the equipment so that the equipment is in good working condition.
This article focuses on the breakdown of the drum section and specific maintenance methods.
First, the drum teeth 1. The problem of dead teeth 1) What is a dead tooth? Because the fuel is not in time, water leakage and hygienic reasons, after a period of operation of the equipment, certain dental metastats are flexible or even inactive, making the spring of the tooth spring fail. This is called death. tooth.
2) Dangers caused by dead teeth Due to the presence of dead teeth, when the paper is handed over, individual teeth are not firmly gripped and paper slips at the mouth, causing some printing problems. There are:
a. The local ghosting tooth row reduces the picking force at the occurrence of dead teeth. When the print product is pulled out between the blanket cylinder and the impression cylinder, the paper slips, and thus local ghosting and sometimes partial wrinkling occur.
b. Overprinting is not allowed due to the reduction of the overall strength of the paper, the paper slippage, resulting in overprinting inaccuracies in the front and back direction of the print, sometimes forming a rejection angle.
c. When the ink volume of the prints is large, the paper will be loosened from the dead teeth, so that the paper cannot be peeled off by the upper party and stuck on the blanket and stick to the blanket. This is the peeling phenomenon.
Dead teeth is one of the main reasons for overprinting faults in printed products. Therefore, the problem of dead teeth must be solved during the overhaul of equipment.
3) to solve the problem of dead teeth a. Remove the dead tooth's tooth, weld the long rod on the scrap tooth, install it on the tooth base (can be more and one), move the tooth base back and forth, add the oil at the same time, until the tooth base can bounce freely.
b. Disassemble the teeth and completely clean the parts in the teeth and reassemble them.
We recommend that all the teeth must be dismantled while they are being repaired. Only in this way can the problem of dead teeth be completely solved. At the same time, we can do a thorough overhaul of the other parts of the teeth row and make the tooth row work well for a long time. status. When disassembling the tooth row, it should be noted that the disassembled parts in the tooth row should be worn with the wire in strict accordance with the original installation order. Do not disturb it when cleaning, otherwise it will not be installed.
When assembling the teeth row, first of all pay attention to the installation sequence, but also carefully examine each tooth base, using a stone of oil to polish the surface of the tooth base in order to avoid burrs. In addition, the position of the pin hole should be carefully checked before installing the hollow pin, so as not to install wrong. After all the rows of teeth have been installed, carefully check the activities of each tooth and do not show any more dead teeth.
2. Replacement of the delicate parts of the tooth row and precautions 1) The accuracy of the open ball of the open teeth is the main one that affects the overprint accuracy of the equipment. Due to the troublesome replacement of the open balls of many rollers, it is in principle necessary to replace all the open balls when setting up for repair. During daily maintenance, the open teeth of the large transfer drum can be removed without disassembling the row.
2) When the dental disc and the dental pad are inspected and repaired, the dental chip and the dental pad are generally replaced.
After installing the tooth row, the teeth and dental pads of the large transfer cylinder and the impression cylinder can be installed, while the teeth and the dental pad of the small transfer cylinder should be installed under the machine.
Before installing the dental pad, the reference surface of the fixed pad should first be cleaned and no burrs should be present. First add the dental pad, tap the pad with the plastic hammer, and then tighten the fixing screw.
When installing tooth teeth, first of all, attention should be paid to the positional relationship between the dental piece and the dental pad, and the close contact between the dental piece and the dental pad should also be ensured. Dedicated steel sheet test can be used, and each printer can also use paper strip test.
Note: If the chip or pad is improperly installed, it will be in favor of broken paper, partial ghosting, peeling and other defects.
3) The teeth of the main teeth of the teeth of the main shaft of the tooth row are easy to produce rust in the place of the dead teeth, and here the tooth base will have a silent wear. If left untreated, after the disassembly of the tooth row is reinstalled, the gap between the teeth is too large. If the conditions are large, the accuracy of the shaft and socket is restored.
4) The spring shaft and bearing in the teeth of other vulnerable parts and the bearing of the tooth row are very easy to damage. It is recommended to prepare before repair.
3. Installation considerations for the row of teeth The row of teeth of the large transfer cylinder has positioning surfaces on only one side. In this way, the upper and lower positions of the rows of teeth can only be aligned with the mattress. Some screws of the 2-needle tooth row are tightened slightly, one tooth pad is installed on each side of the tooth row, and the gum pad is knocked on with the gum hammer (or the bar is lifted with a crowbar) until the highest point of the tooth pad and the height of the roller surface are achieved. Consistent. There may be a dial indicator to check the height of the dental pad, or you can check it with a sense of sensation. Adjust all the screws that fix the teeth after installation and install a tooth chip and a dental pad.
Due to accidents and other reasons, after a long period of use, errors may occur in the data of the bolster seat adjustment screw of the small transfer drum. Therefore, before installation, the position of the pedestal seat height should be recalibrated.
4. Transfer time issues The issue of the transfer time of the tooth row is one of the main factors that affect the accuracy of equipment overprinting. We recommend that the adjustment be strictly in accordance with the standard data of the sea coordination.
1) The determination of the machine 0 point In each press roller edge of the drive surface, the drum body near the groove of the bearer has a red mark (marked with D), the line of a set of D reticle is the 0 point of the printing press Positioning line. There is a hole with a diameter of 12mm at the corresponding position of the wallboard. This hole has a working position of 0-position and installs the positioning method.
2) The dial is installed on the protective cover of the transmission surface, take out the sealing cover on the small transfer roller, and the main shaft is fixed and fastened. Mount the dial on the shaft, install the pointer, and position 0 points.
3) Angle Values ​​Only the transfer angle parameters of a group of Heidelberg 102V glue machines are listed here. (To be continued)
This article focuses on the breakdown of the drum section and specific maintenance methods.
First, the drum teeth 1. The problem of dead teeth 1) What is a dead tooth? Because the fuel is not in time, water leakage and hygienic reasons, after a period of operation of the equipment, certain dental metastats are flexible or even inactive, making the spring of the tooth spring fail. This is called death. tooth.
2) Dangers caused by dead teeth Due to the presence of dead teeth, when the paper is handed over, individual teeth are not firmly gripped and paper slips at the mouth, causing some printing problems. There are:
a. The local ghosting tooth row reduces the picking force at the occurrence of dead teeth. When the print product is pulled out between the blanket cylinder and the impression cylinder, the paper slips, and thus local ghosting and sometimes partial wrinkling occur.
b. Overprinting is not allowed due to the reduction of the overall strength of the paper, the paper slippage, resulting in overprinting inaccuracies in the front and back direction of the print, sometimes forming a rejection angle.
c. When the ink volume of the prints is large, the paper will be loosened from the dead teeth, so that the paper cannot be peeled off by the upper party and stuck on the blanket and stick to the blanket. This is the peeling phenomenon.
Dead teeth is one of the main reasons for overprinting faults in printed products. Therefore, the problem of dead teeth must be solved during the overhaul of equipment.
3) to solve the problem of dead teeth a. Remove the dead tooth's tooth, weld the long rod on the scrap tooth, install it on the tooth base (can be more and one), move the tooth base back and forth, add the oil at the same time, until the tooth base can bounce freely.
b. Disassemble the teeth and completely clean the parts in the teeth and reassemble them.
We recommend that all the teeth must be dismantled while they are being repaired. Only in this way can the problem of dead teeth be completely solved. At the same time, we can do a thorough overhaul of the other parts of the teeth row and make the tooth row work well for a long time. status. When disassembling the tooth row, it should be noted that the disassembled parts in the tooth row should be worn with the wire in strict accordance with the original installation order. Do not disturb it when cleaning, otherwise it will not be installed.
When assembling the teeth row, first of all pay attention to the installation sequence, but also carefully examine each tooth base, using a stone of oil to polish the surface of the tooth base in order to avoid burrs. In addition, the position of the pin hole should be carefully checked before installing the hollow pin, so as not to install wrong. After all the rows of teeth have been installed, carefully check the activities of each tooth and do not show any more dead teeth.
2. Replacement of the delicate parts of the tooth row and precautions 1) The accuracy of the open ball of the open teeth is the main one that affects the overprint accuracy of the equipment. Due to the troublesome replacement of the open balls of many rollers, it is in principle necessary to replace all the open balls when setting up for repair. During daily maintenance, the open teeth of the large transfer drum can be removed without disassembling the row.
2) When the dental disc and the dental pad are inspected and repaired, the dental chip and the dental pad are generally replaced.
After installing the tooth row, the teeth and dental pads of the large transfer cylinder and the impression cylinder can be installed, while the teeth and the dental pad of the small transfer cylinder should be installed under the machine.
Before installing the dental pad, the reference surface of the fixed pad should first be cleaned and no burrs should be present. First add the dental pad, tap the pad with the plastic hammer, and then tighten the fixing screw.
When installing tooth teeth, first of all, attention should be paid to the positional relationship between the dental piece and the dental pad, and the close contact between the dental piece and the dental pad should also be ensured. Dedicated steel sheet test can be used, and each printer can also use paper strip test.
Note: If the chip or pad is improperly installed, it will be in favor of broken paper, partial ghosting, peeling and other defects.
3) The teeth of the main teeth of the teeth of the main shaft of the tooth row are easy to produce rust in the place of the dead teeth, and here the tooth base will have a silent wear. If left untreated, after the disassembly of the tooth row is reinstalled, the gap between the teeth is too large. If the conditions are large, the accuracy of the shaft and socket is restored.
4) The spring shaft and bearing in the teeth of other vulnerable parts and the bearing of the tooth row are very easy to damage. It is recommended to prepare before repair.
3. Installation considerations for the row of teeth The row of teeth of the large transfer cylinder has positioning surfaces on only one side. In this way, the upper and lower positions of the rows of teeth can only be aligned with the mattress. Some screws of the 2-needle tooth row are tightened slightly, one tooth pad is installed on each side of the tooth row, and the gum pad is knocked on with the gum hammer (or the bar is lifted with a crowbar) until the highest point of the tooth pad and the height of the roller surface are achieved. Consistent. There may be a dial indicator to check the height of the dental pad, or you can check it with a sense of sensation. Adjust all the screws that fix the teeth after installation and install a tooth chip and a dental pad.
Due to accidents and other reasons, after a long period of use, errors may occur in the data of the bolster seat adjustment screw of the small transfer drum. Therefore, before installation, the position of the pedestal seat height should be recalibrated.
4. Transfer time issues The issue of the transfer time of the tooth row is one of the main factors that affect the accuracy of equipment overprinting. We recommend that the adjustment be strictly in accordance with the standard data of the sea coordination.
1) The determination of the machine 0 point In each press roller edge of the drive surface, the drum body near the groove of the bearer has a red mark (marked with D), the line of a set of D reticle is the 0 point of the printing press Positioning line. There is a hole with a diameter of 12mm at the corresponding position of the wallboard. This hole has a working position of 0-position and installs the positioning method.
2) The dial is installed on the protective cover of the transmission surface, take out the sealing cover on the small transfer roller, and the main shaft is fixed and fastened. Mount the dial on the shaft, install the pointer, and position 0 points.
3) Angle Values ​​Only the transfer angle parameters of a group of Heidelberg 102V glue machines are listed here. (To be continued)