SOR Series, 102 Series Offset Press (3)

7. Roller bearing wear formed by a manufacturer Heidelberg 102V offset press a second group of ink bars appear, characterized by the operating surface of the ink bar is heavier, gradually reducing and disappearing toward the transmission surface. After checking the pressure of the water and ink rollers, they are very political parties. Examine the plate cylinder and blanket cylinder and notice that there are also ink bars on the plate and cloth. The inching machine moves the ink stick to the tangent point of the plate roller roll and finds that the impression cylinder and the rubber cylinder are just turning to the contact position of the edge. Through analysis, in the printing process, when the impression cylinder is in contact with the edge of the blanket cylinder, due to the pressure, the blanket cylinder jumps without producing movement between the printing cylinder and the screen dots, forming an ink bar. Check the run-out of the roller bearing on the operation surface of the blanket cylinder and find that the combined pressure jump value is 0.17mm and the pressure-extraction jump value is 0.02mm. It proves that the bearing of the rubber roller operating surface is seriously worn. After the roller bearings are replaced, the ink bars disappear.
8. Defective drum thrust bearing formed a ghost image Heidelberg 102V offset presses were not allowed in the first and second colors. In the four-color printing, it was found that there was a horizontal ghost in the second color, and there was no ghosting in the first and third and fourth colors. This proves that the fault is in one of the second or second group and the third group. The second inspection revealed that there was no ghosting when only the second color was printed. Therefore, it was considered that the cause of the failure was during the handover of the second and third groups. Inspection of the drum with a row of teeth, found that the large paper roller thrust bearing wear punished, replace the bearing ghost disappeared.
9. Printing oil rejection phenomenon When printing at a factory Heidelberg 102V four-color offset printing press, the transmission surface of the product often has oil spots. Inspection revealed that oil leakage occurred at the shaft sleeve of the first-color impression cylinder, and analyzed that oil would be thrown onto the print when the machine was running. Some people diagnosed that the embossing roll was damaged by the same seal, and it is recommended to replace the oil seal, but it was not implemented due to the high cost.
This is a common fault. The structure of the drum sleeve should be analyzed first. The sealing method is a labyrinth seal. There are oil holes on the shaft sleeve, and there is a separate oil pipe for shower lubrication. The oil is drained back to the tank through the oil return hole. In long-term operation, dust and dust in the environment will enter the sleeve and the oil return hole will be blocked, so the oil will spill from the inside of the sleeve and thrown on the print.
Dismantling the drive shaft sleeve and cleaning the oil return hole of the shaft sleeve can solve the oil rejection problem without having to replace the oil (oil seal)
Fifth, 102V four-color offset printing cylinder overhaul program Solve all tooth problems and solve dead teeth problems:
2. Replace all open teeth, teeth, and dental pads;
3. Replace worn tooth row bearing, spring rod bearing, spring rod shaft and tooth socket copper sleeve;
4. Repair worn teeth row shafts;
5. Correct the height of the small transfer drum;
6. Adjust all plate clamps;
7. Replace worn roller bearings and thrust bearings;
8. Repair deformed rollers (as needed)
9. Clean all impression roller bearing surfaces;
10. Clean all roller bearings as required;
11. Fully adjust the tooth transfer time.
J2205 Exclusion of Double-color Offset Double-sided Offset Presses Our factory has two J2205 off-color two-color offset presses produced by Beiren. One of the J2205 off-color two-color offset presses produced by Beiren was found in early 1993. Phenomenon, from the mouth to the suppression of the tip, have a serious impact on the quality of printing.
In response to this ghosting phenomenon, our mechanic and operatives have compared and analyzed the current product with the previous product and found that this situation has been working for a while, but before the ghosting was not obvious, as long as the increase Printing pressure is better. However, the phenomenon of ghosting in the same shifts has become increasingly serious. The quality requirements cannot be met, and the life of the printing plate is short. If it is less than the prescribed printed cable, it begins to blur and even disappears.
Based on the above, we conducted a comprehensive step-by-step inspection of the machine. First, we re-high-speed the lining of the embossing cylinder with two sets of blanket cylinders and two sets of printing rollers to meet specifications and standards to prevent excessive pressure. Too thick and cause the blanket deformation aging, Li Ying. Then the pressure of the gripper on the impression cylinder is adjusted so that the grip force is increased and stable. After the graphic on the blanket is transferred to the paper, there are enough countries to pull the paper down to avoid insufficient tension. Causes ghosting.
Through the above debugging, the effect is not obvious. Therefore, the ghost image of people is improperly ruled out by improper operation or adjustment. Then we focused on the second plate cylinder, rubber cylinder drive mechanism, now the printing drum is more serious in the circumferential swing, the machine in the static state of the plate roller surface longitudinal movement of 0.5-1mm, and rubber blanket on the blanket The graphic and text also have obvious ghosting. According to this phenomenon can be determined due to the plate cylinder in the mechanical transmission of excessive clearance, causing the roller to swing in the circumference, resulting in heavy ... We found during the inspection process plate cylinder adjustment longitudinal magnetic printing device axis ( N73-20504) Loosely, remove the fixed small shaft hub (N113-205021) and find that there is clearance between the small shaft and the fixing hole on the hub (should fit into the interference, and the two M6 hexagon socket bolts fixing the small shaft on the hub) Has been broken, small shaft and the connection plate (N73-20507) hole with the gap is too large, there is a turbulent phenomenon, resulting in the printing plate cylinder swinging and civil shadow.
During the repair process, we measured the boring holes of the small shafts of the small hole on the hub and found that both holes were out of round and flared. Re-clamp the holes to re-align the small shafts according to the size and fit accuracy after repair. The hub is fitted with interference, the shaft is 15-20, after pressing, it is fixed with 2 M6 internal hexagon bolts. The connecting shaft hole is dynamic and the hole is 15-20. After reinstalling, the ghost disappeared and the printing returned to normal.
Manroland single-color offset press before the emergency troubleshooting three cases of secondary offset press because of its low failure rate, stable and reliable operation, etc., often comparable to some domestic new machines. However, due to the general lack of drawing materials and components, maintenance work has been difficult. Once the machine fails, how to adjust measures to local conditions, draw materials locally, and restore machine operations as soon as possible becomes a critical segment that affects the economic benefits of the enterprise. The following brief description of the three emergency measures in our maintenance practice is as follows.
Manroland front gauge is U34. When the board fails, it shows that the machine can pressurize, but it will not separate automatically in the absence of paper and squat. The same phenomenon can be caused by a variety of reasons, when it differs.
Fault 1: Check that the NAND gate 2 is damaged (failure check process). After troubleshooting, it was found that the integrated block is different from the general model and it is difficult to replace it with an ordinary integrated block. To this end, a NAND gate circuit is connected by a separate element. After the main point is connected, the machine resumes operation.
Fault 2: The synchronous relay Rr2 is damaged. Rr2 is a solid state relay on the circuit board, following the synchronous proximity switch action, and its corner control transistor T12 sends a synchronous fat rush signal. When the machine's printing speed reaches 10,000 sheets per hour, the relay operates about 3 times per second. According to this calculation, using the same type of general-purpose relay can be competent, so choose a micro-internal relay installed test, the working speed fully meets the requirements of the machine.
Fault 3: The sync pulse transistor T12 is damaged. The circuit pulls in 4d29 when the machine is fully pressed, and +24V is sent to the T12 emitter through 4d29. When Rr2 is closed with the synchronization signal, T12 is turned on and the synchronization pulse is sent out by MP6 and D11. According to the analysis of the circuit principle, the transistor T12 can be replaced with the normally open point of the intermediate relay Rr2 that was replaced in the fault 2, and then it is connected between the emitter and the collector of the T12, and the pulse signal is sent directly, so that the machine can resume operation.
The above three cases of failures occurred in succession on the same machine. Using the emergency measures described in the article, the results were more effective, and the long-term operation of the machine was guaranteed. But need to explain is: (to be continued)