Coiling machine valve hydraulic control system and method capable of automatically adjusting gap

Abstract

The invention discloses a recoiling machine valve hydraulic control system and method capable of automatically adjusting gaps. According to the system, a pressure stop valve, a servo valve, a first electromagnetic valve, a second electromagnetic valve, a position sensor, a pressure sensing switch and two pressure sensors form the hydraulic control system of a recoiling machine operation side valve driving hydraulic cylinder and a recoiling machine transmission side valve driving hydraulic cylinder. According to the method, first calibration is carried out after the hydraulic control system is installed for the first time, and second calibration is carried out after an upper pinch roll or related equipment is replaced; when the steel coil head reaches a frame at the tail end of the rolling mill, the valve is opened at a low speed and is switched to a pressure control mode, the position of the valve is controlled according to the thickness of the steel coil head, the valve returns to a closed state after the steel coil head enters the upper pinch roll, and the steel coil is wound on a well body of a coiling machine through a gap between the valve and the upper pinch roll. According to the hydraulic control system and method, online adjustment of the gap between the valve opening position and the upper pinch roll in the production state is achieved, reliable coiling of a steel coil is ensured, and the operation safety of equipment is improved.

Description

Technical Field

[0001] The invention relates to the technical field of metallurgical equipment control, and in particular to a hydraulic control system and method for a coiler valve with automatically adjustable clearance. Background Art

[0002] The valve is used for the coiler in the steel hot-rolled coil production plant. When producing hot-rolled coils, an underground coiler is usually used to coil the strip output from the rolling mill into a coil. The valve, also called a switch plate, is used to guide the strip from the coiler's pinch rollers into the coiler shaft for coiling.

[0003] like Figure 1 and Figure 2 As shown, the valve 1 is installed directly behind the upper pinch roller 2 and has two tasks in the coiler: 1. For the coiler 3 that is ready for coiling, the valve 1 is lifted up and opened to release the coil head 4 into the coiler 3 shaft; 2. For the coiler 3 that is not ready for coiling, the valve 1 is pressed down to close and block the steel coil head 4 from entering the coiler 3 shaft, and the steel coil head 4 is guided to the coiler scrap collector 5 that is ready at the rear.

[0004] The movement of the valve is carried out with the help of two hydraulic cylinders on the operating side and the transmission side. The two hydraulic cylinders are controlled by a three-position functional valve to control the lifting and lowering of the hydraulic cylinders to realize the opening and closing of the valve. There is a proximity switch at the opening and closing position of the valve to detect whether the valve is opened and closed in place.

[0005] The opening and closing positions of the valve in the coiler are determined by mechanical stops and need to be adjusted manually. When the valve is closed, it is horizontal and coplanar with the roller table. When the valve is open, the gap between the upper pinch roller 2 is closed, and the gap is 0 mm. The stop position of the valve 1 is adjusted so that the gap between it and the upper pinch roller 2 is as small as possible and there is no contact.

[0006] The traditional valve mechanism has the following disadvantages: 1. Every time the valve or valve hydraulic cylinder is replaced, the gap between the valve opening position and the upper pinch roller working position needs to be adjusted manually and the stop position needs to be reconfirmed.

[0007] 2. Generally, the service life of the pinch roller is 4 weeks, and the replacement cycle of the valve is much longer. After each replacement of the pinch roller, the gap needs to be manually readjusted due to changes in the roller diameter of the pinch roller. The maintenance time is difficult to meet the needs, and the adjustment accuracy cannot be guaranteed.

[0008] 3. Once the gap between the valve and the upper pinch roller is too small, the valve will scrape the pinch roller, causing scratches on the pinch roller surface; if the gap between the valve and the pinch roller is too large, when the thin plate is coiled, the strip will slip through the gap to the next coiler and enter the collector, causing scrap steel or batch quality loss due to scratches on the pinch roller.

[0009] 4. The valve hydraulic cylinder pressure is taken from the system pressure, and there is no separate shut-off valve. During continuous production, the system pressure is supplied to other equipment and it is not suitable to release the pressure, which brings difficulties and safety risks to the gap adjustment. Summary of the invention

[0010] The technical problem to be solved by the present invention is to provide a hydraulic control system and method for the coiler valve with automatically adjustable gap. The hydraulic control system and method overcome the defects of traditional valve control, realize online adjustment of the gap between the valve opening position and the upper pinch roller under production status, and do not need to make complicated gap adjustments during equipment installation, thus avoiding valve gap deviation caused by replacement of the upper pinch roller, ensuring reliable coiling of steel coils and improving the safety of equipment operation.

[0011] In order to solve the above technical problems, the hydraulic control system of the winding machine valve with automatically adjustable gap of the present invention includes two hydraulic cylinders driven by the valves on the operating side and the transmission side of the winding machine, a pressure cut-off valve, a servo valve, a first solenoid valve, a second solenoid valve, a position sensor, a pressure sensing switch and two pressure sensors. The input end of the pressure cut-off valve is connected to the hydraulic source, and the output end is respectively connected to the input ends of the servo valve, the first solenoid valve and the second solenoid valve. The output end of the servo valve is respectively connected to the live rod chambers of the two hydraulic cylinders, the output end of the first solenoid valve is connected to the live rod chambers of the two hydraulic cylinders, and the output end of the second solenoid valve is connected to the rodless chambers of the two hydraulic cylinders. The position sensor is placed in any hydraulic cylinder and feeds back the position of the valve. The two pressure sensors respectively detect the hydraulic pressure of the live rod chamber and the rodless chamber of the two hydraulic cylinders. The pressure sensing switch is arranged at the output end of the pressure cut-off valve and feeds back the pressure signal of the hydraulic source.

[0012] A hydraulic control method for a coiler valve with automatically adjustable clearance based on the above hydraulic control system comprises the following steps: Step 1: After the initial installation of the hydraulic control system, the first calibration is performed. The upper pinch roller runs at the lowest set speed. The valve is manually operated to the lowest mechanical limit position. Zero point calibration is performed through the hydraulic control system operation panel. The position sensor value of the lowest mechanical limit position is latched. The upper pinch roller is manually operated to descend so that the roller gap is zero. Step 2: Keep the roller gap at zero and the upper pinch roller running at a low speed, manually lift the valve until the valve pressure reaches the set pressure, and check whether the valve contacts the upper pinch roller. If so, lower the valve to the lowest position again and reduce the valve set pressure. If not, lower the valve to the lowest position again and increase the valve set pressure. Step 3: Keep the roller gap at zero and the upper pinch roller running at a low speed, manually lift the valve until the valve pressure reaches the minimum pressure that can contact the upper pinch roller, and latch the corresponding position sensor value through the hydraulic control system operation panel; Step 4: Subtract 2mm from the position sensor value as the valve waiting position calibration, and the valve automatically drops to the lowest position again to complete the first calibration; Step 5. After the upper pinch roller or related equipment is replaced, recalibrate the valve closing position and waiting position; keep the upper pinch roller running at a low speed, automatically close the valve at half speed to the lowest mechanical limit position, perform zero point calibration through the hydraulic control system operation panel, and latch the position sensor value of the lowest mechanical limit position; Step 6: Automatically operate the upper pinch roller to descend, so that the roller gap is zero, keep the roller gap at zero and the upper pinch roller running at a low speed, manually lift the valve until the valve pressure reaches the minimum pressure that can contact the upper pinch roller, and latch the corresponding position sensor value through the hydraulic control system operation panel; Step 7: Subtract 2mm from the position sensor value as the valve waiting position calibration, and the valve automatically drops to the lowest position again to complete the secondary calibration; Step 8: After the valve closing position and the waiting position are calibrated, the valve is returned to the closed state. After the coiler is switched to the ready state, the valve is opened from the closed position to the waiting position. Step 9: When the head of the steel coil reaches the end stand of the rolling mill, the valve opens at a low speed until the set minimum pressure setting value is reached; Step 10: Switch the valve to the pressure control mode and keep the pressure control for 1 second. If the thickness of the steel coil head is ≤8mm, the valve drives the hydraulic cylinder to decrease by 1mm, and the steel coil head enters the upper pinch roller, and then the valve drives the hydraulic cylinder to decrease by 2mm; if the thickness of the steel coil head is greater than 8mm, the valve drives the hydraulic cylinder to decrease by 2mm, and the steel coil head enters the upper pinch roller; Step 11: After the lead of the steel coil enters the upper pinch roller, the valve returns to the closed state, and the steel coil passes through the gap between the valve and the upper pinch roller and is wound around the coiler shaft.

[0013] Furthermore, when the valve is closed to the lowest mechanical limit position in step 1 and step 5, the lowest mechanical limit position is manually confirmed. Since the hydraulic control system and method of the coiler valve with automatically adjustable gap of the present invention adopts the above technical scheme, that is, the input end of the pressure cut-off valve of the system is connected to the hydraulic source, the output end is respectively connected to the input end of the servo valve and the first and second solenoid valves, the output end of the servo valve is respectively connected to the active rod chambers of the two hydraulic cylinders, the output end of the first solenoid valve is connected to the active rod chambers of the two hydraulic cylinders, and the output end of the second solenoid valve is connected to the rodless chambers of the two hydraulic cylinders, the position sensor is placed in any hydraulic cylinder and feedbacks the position of the valve, the two pressure sensors respectively detect the hydraulic pressure of the active rod chamber and the rodless chamber of the two hydraulic cylinders, and the pressure sensing switch is arranged at the output end of the pressure cut-off valve and feedbacks the pressure signal of the hydraulic source. The method performs the first calibration after the initial installation of the hydraulic control system, and performs the second calibration after the upper pinch roller or related equipment is replaced; when the steel coil strip head reaches the end frame of the rolling mill, the valve is opened at a low speed, the valve is switched to the pressure control mode, and the valve position is controlled according to the thickness of the steel coil strip head. After the steel coil strip head enters the upper pinch roller, the valve returns to the closed state, and the steel coil passes through the gap between the valve and the upper pinch roller and is wound on the coiler shaft. The hydraulic control system and method overcome the defects of traditional valve control and realize online adjustment of the gap between the valve opening position and the upper pinch roller under production status. There is no need to make complicated gap adjustments during equipment installation, which avoids valve gap deviation caused by replacement of the upper pinch roller, ensures reliable coiling of the steel coil and improves the safety of equipment operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments: Figure 1 Schematic diagram of the coiler valve opening; Figure 2 Schematic diagram of coiler valve closing; Figure 3 It is a schematic diagram of a hydraulic control system for a coiler valve with automatically adjustable clearance according to the present invention; Figure 4 A flowchart of the method is shown in FIG. DETAILED DESCRIPTION

[0015] Implementation example Figure 3As shown, the hydraulic control system of the valve of the coiler with automatically adjustable gap of the present invention comprises two hydraulic cylinders 1 driven by the valves on the operating side and the transmission side of the coiler, a pressure cut-off valve 2, a servo valve 3, a first solenoid valve 4, a second solenoid valve 5, a position sensor 6, a pressure sensing switch 7 and two pressure sensors 8, the input end of the pressure cut-off valve 2 is connected to the hydraulic source P, and the output end is respectively connected to the input ends of the servo valve 3, the first solenoid valve 4 and the second solenoid valve 5, the output end of the servo valve 3 is respectively connected to the active rod chambers of the two hydraulic cylinders 1, the output end of the first solenoid valve 4 is connected to the active rod chambers of the two hydraulic cylinders 1, the output end of the second solenoid valve 5 is connected to the rodless chambers of the two hydraulic cylinders 1, the position sensor 6 is placed in any hydraulic cylinder 1 and feeds back the position of the valve, the two pressure sensors 8 respectively detect the hydraulic pressure of the active rod chamber and the rodless chamber of the two hydraulic cylinders 1, and the pressure sensing switch 7 is arranged at the output end of the pressure cut-off valve 2 and feeds back the pressure signal of the hydraulic source P.

[0016] like Figure 4 As shown, a hydraulic control method for a coiler valve with automatically adjustable clearance based on the above hydraulic control system comprises the following steps: Step 1: After the initial installation of the hydraulic control system, the first calibration is performed. The upper pinch roller runs at the lowest set speed. The valve is manually operated to the lowest mechanical limit position. Zero point calibration is performed through the hydraulic control system operation panel. The position sensor value of the lowest mechanical limit position is latched. The upper pinch roller is manually operated to descend so that the roller gap is zero. Step 2: Keep the roller gap at zero and the upper pinch roller running at a low speed, manually lift the valve until the valve pressure reaches the set pressure, and check whether the valve contacts the upper pinch roller. If so, lower the valve to the lowest position again and reduce the valve set pressure. If not, lower the valve to the lowest position again and increase the valve set pressure. Step 3: Keep the roller gap at zero and the upper pinch roller running at a low speed, manually lift the valve until the valve pressure reaches the minimum pressure that can contact the upper pinch roller, and latch the corresponding position sensor value through the hydraulic control system operation panel; Step 4: Subtract 2mm from the position sensor value as the valve waiting position calibration, and the valve automatically drops to the lowest position again to complete the first calibration; Step 5. After the upper pinch roller or related equipment is replaced, recalibrate the valve closing position and waiting position; keep the upper pinch roller running at a low speed, automatically close the valve at half speed to the lowest mechanical limit position, perform zero point calibration through the hydraulic control system operation panel, and latch the position sensor value of the lowest mechanical limit position; Step 6: Automatically operate the upper pinch roller to descend, so that the roller gap is zero, keep the roller gap at zero and the upper pinch roller running at a low speed, manually lift the valve until the valve pressure reaches the minimum pressure that can contact the upper pinch roller, and latch the corresponding position sensor value through the hydraulic control system operation panel; Step 7: Subtract 2mm from the position sensor value as the valve waiting position calibration, and the valve automatically drops to the lowest position again to complete the secondary calibration; Step 8: After the valve closing position and the waiting position are calibrated, the valve is returned to the closed state. After the coiler is switched to the ready state, the valve is opened from the closed position to the waiting position. Step 9: When the head of the steel coil reaches the end stand of the rolling mill, the valve opens at a low speed until the set minimum pressure setting value is reached; Step 10: Switch the valve to the pressure control mode and keep the pressure control for 1 second. If the thickness of the steel coil head is ≤8mm, the valve drives the hydraulic cylinder to decrease by 1mm, and the steel coil head enters the upper pinch roller, and then the valve drives the hydraulic cylinder to decrease by 2mm; if the thickness of the steel coil head is greater than 8mm, the valve drives the hydraulic cylinder to decrease by 2mm, and the steel coil head enters the upper pinch roller; Step 11: After the lead of the steel coil enters the upper pinch roller, the valve returns to the closed state, and the steel coil passes through the gap between the valve and the upper pinch roller and is wound around the coiler shaft.

[0017] Preferably, when the valve is closed to the lowest mechanical limit position in step 1 and step 5, the lowest mechanical limit position is confirmed manually.

[0018] The first calibration of this hydraulic control system is used for the initial installation of the equipment, mainly to confirm the minimum pressure setting value, the purpose is to minimize the damage to the equipment caused by the pressure, and to calibrate the closed position and the waiting position. The second calibration is used for the replacement of the pinch roller or other related equipment, and the closed position and the waiting position need to be recalibrated.

[0019] Compared with the original control mechanism, this hydraulic control system has one more waiting position in automatic operation, and the final gap positioning is triggered by the strip material tracking. In automatic operation, for strips less than 8 mm, the valve gap reaches the set pressure 1s later and is first controlled by the 1mm cylinder stroke gap. After the strip enters the coiler, the gap is then set to the 2mm cylinder stroke. In automatic operation, for strips greater than or equal to 8 mm, the valve gap reaches the set pressure and is directly set to the 2mm cylinder stroke.

[0020] The hydraulic control system and method have the following characteristics: 1. During the equipment installation, just ensure that the mechanical limit position of the valve closing is horizontal and in the same plane as the roller table and the lower pinch roller; 2. The gap between the valve opening position and the upper pinch roller can be adjusted online in production mode, eliminating the need for complex gap adjustment during equipment installation; 3. Avoid valve clearance deviation caused by roller diameter deviation of the upper pinch roller after replacement, which may scratch the surface of the upper pinch roller due to lack of clearance; 4. Avoid the valve gap deviation caused by the roller diameter deviation of the pinch roller after the upper pinch roller is replaced. The thin strip steel cannot be introduced into the coiler shaft due to the warping of the head plate due to the excessive gap, and passes through the gap to become scrap steel; 5. Add a separate pressure cut-off valve for the valve hydraulic cylinder to improve equipment safety.

[0021] Beneficial Effects 1. The equipment installation is simplified, and you only need to confirm and adjust the valve closing position stop position.

[0022] 2. Avoid the change of the gap between the valve and the upper pinch roller caused by the replacement of the upper pinch roller, which may cause the valve to scrape the upper pinch roller and damage the surface of the upper pinch roller.

[0023] 3. Avoid the change of the gap between the valve and the upper pinch roller caused by the replacement of the upper pinch roller, which causes the strip steel to pass through the gap of the valve and become scrap steel.

[0024] 4. The safety stop function cuts off the pressure source of the valve hydraulic cylinder, which enhances the safety of equipment adjustment operations.

Claims

1. A hydraulic control system for a coiler valve with automatically adjustable clearance, comprising two hydraulic cylinders driving the coiler valves on the operating side and the transmission side, characterized in that: It also includes a pressure cut-off valve, a servo valve, a first solenoid valve, a second solenoid valve, a position sensor, a pressure sensing switch and two pressure sensors. The input end of the pressure cut-off valve is connected to the hydraulic source, and the output end is respectively connected to the input ends of the servo valve, the first solenoid valve and the second solenoid valve. The output end of the servo valve is respectively connected to the live rod chambers of the two hydraulic cylinders, the output end of the first solenoid valve is connected to the live rod chambers of the two hydraulic cylinders, and the output end of the second solenoid valve is connected to the rodless chambers of the two hydraulic cylinders. The position sensor is placed in any hydraulic cylinder and feeds back the position of the valve. The two pressure sensors respectively detect the hydraulic pressure of the live rod chamber and the rodless chamber of the two hydraulic cylinders. The pressure sensing switch is arranged at the output end of the pressure cut-off valve and feeds back the pressure signal of the hydraulic source.

2. A hydraulic control method for a coiler valve with automatically adjustable clearance based on the hydraulic control system of claim 1, characterized in that The steps include: Step 1: After the initial installation of the hydraulic control system, the first calibration is performed. The upper pinch roller runs at the lowest set speed. The valve is manually operated to the lowest mechanical limit position. Zero point calibration is performed through the hydraulic control system operation panel. The position sensor value of the lowest mechanical limit position is latched. The upper pinch roller is manually operated to descend so that the roller gap is zero. Step 2: Keep the roller gap at zero and the upper pinch roller running at a low speed, manually lift the valve until the valve pressure reaches the set pressure, and check whether the valve contacts the upper pinch roller. If so, lower the valve to the lowest position again and reduce the valve set pressure. If not, lower the valve to the lowest position again and increase the valve set pressure. Step 3: Keep the roller gap at zero and the upper pinch roller running at a low speed, manually lift the valve until the valve pressure reaches the minimum pressure that can contact the upper pinch roller, and latch the corresponding position sensor value through the hydraulic control system operation panel; Step 4: Subtract 2mm from the position sensor value as the valve waiting position calibration, and the valve automatically drops to the lowest position again to complete the first calibration; Step 5. After the upper pinch roller or related equipment is replaced, recalibrate the valve closing position and waiting position; keep the upper pinch roller running at a low speed, automatically close the valve at half speed to the lowest mechanical limit position, perform zero point calibration through the hydraulic control system operation panel, and latch the position sensor value of the lowest mechanical limit position; Step 6: Automatically operate the upper pinch roller to descend, so that the roller gap is zero, keep the roller gap at zero and the upper pinch roller running at a low speed, manually lift the valve until the valve pressure reaches the minimum pressure that can contact the upper pinch roller, and latch the corresponding position sensor value through the hydraulic control system operation panel; Step 7: Subtract 2mm from the position sensor value as the valve waiting position calibration, and the valve automatically drops to the lowest position again to complete the secondary calibration; Step 8: After the valve closing position and the waiting position are calibrated, the valve is returned to the closed state. After the coiler is switched to the ready state, the valve is opened from the closed position to the waiting position. Step 9: When the head of the steel coil reaches the end stand of the rolling mill, the valve opens at a low speed until the set minimum pressure setting value is reached; Step 10: Switch the valve to the pressure control mode and keep the pressure control for 1 second. If the thickness of the steel coil head is ≤8mm, the valve drives the hydraulic cylinder to decrease by 1mm, and the steel coil head enters the upper pinch roller, and then the valve drives the hydraulic cylinder to decrease by 2mm; if the thickness of the steel coil head is greater than 8mm, the valve drives the hydraulic cylinder to decrease by 2mm, and the steel coil head enters the upper pinch roller; Step 11: After the lead of the steel coil enters the upper pinch roller, the valve returns to the closed state, and the steel coil passes through the gap between the valve and the upper pinch roller and is wound around the coiler shaft.

3. The hydraulic control method for the valve of a coiler with automatically adjustable clearance according to claim 2 is characterized in that: When the valve is closed to the lowest mechanical limit position in step 1 and step 5, the lowest mechanical limit position is confirmed manually.

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