The rolling machine safe operation rules is a professional equipment for plastic processing of the plate, the upper work roller is the core component to complete the coiling, the coil force is very large, will produce deflection, the pressure distribution of the steel plate is not uniform, resulting in defective products.How to reduce torsion, the current methods mainly include:
1. The upper work roller is designed into a waist drum shape
During the design, the diameter of the working part of the work roller is gradually reduced from the middle to the two ends.When rolling plate, the upper roller is subjected to the upward bending force, which is just offset with the middle part of the waist drum shape, so that the upper roller basically tends to be straight.
This method is widely used in plate winding machine and is adopted by most designers.Although the design can play a certain compensation effect, but it is difficult to calculate and manufacture.
2. Add support for the upper work roll
The method provides a supporting beam and a supporting roller for the upper work roll.By adjusting the height of the supporting roll, the upper work roll can produce a certain pre-deformation downward, which can just offset the upward deformation of the upper work roll when winding plate, so as to achieve the purpose of deflection compensation.
This method is mostly used for autocratic width of the larger rolling machine, such as Marine rolling machine and oil storage and transportation tank rolling.And can only roll circular arc plate or workpiece with large diameter of drum.
3. Set up lifting support
The method for the upper and lower roller set can lift support beam and backup roll, when the plate end bending stress is larger, can produce flexure deformation work roll, the cut down the support beam, bearing on the work roll, reduce its deformation, after bending, roll round, rises will support beam and shell can be through the work roll and backup roll on.
This method is suitable for the workpiece with small drum diameter and requiring plate end prebending.
4. Use back pressure
In this method, the deflection of the upper work roll is reduced through the action of back pressure, and two hydraulic cylinders are installed on the outside of the frame to exert back pressure on both ends of the upper roll vertically, respectively, so that the middle section of the upper roll produces downward bending deformation, so as to eliminate the deformation caused by insufficient deflection of the upper roll.
The advantage of this method is that the amount of compensation varies with the load, but the disadvantage is that the mechanical structure is complex, the calculation is difficult and the cost is high.Foreign companies have produced this type of model, domestic only a few manufacturers at present.
Each of these methods has its advantages and disadvantages.In the actual design, should be combined with the coil machine working conditions, manufacturing costs, etc., choose the appropriate scheme.
The safe operation rules of the rolling machine are as follows:
First, preparation before starting
1, must be put in the workpiece stable, positive
1. Check whether there is any abnormity in each part, and the fastening screw (cap) shall not be loose.Brake should be normal and reliable.
2. Adjust the distance of the reel strictly according to the thickness of the plate, and shall not overload operation.Do not roll the workpiece beyond the specified range of mechanical properties.
II. Matters needing attention in operation
1, the workpiece must be put smoothly, the position is positive before starting operation, and should be clear signal, designated one person to command.
2. Hands shall not be placed on the rolled steel plate, and the sample is not allowed to be used for inspection. After shutdown, the sample shall be used to check the roundness.
3. When the workpiece is not fully rolled, a certain amount of margin should be reserved when it rolls to the end of the steel plate to prevent the workpiece from falling and wounding.
4. When working, it is strictly prohibited to stand on the workpiece or find the correct roundness on the cylinder that has been rolled.
5. When rolling thick, large diameter cylinder or material strength workpiece, a small amount of moving roller should be lowered and formed by rolling for many times.
6. When rolling a narrow cylinder, it should be rolled in the middle of the roll.
7. After the workpiece enters the roll, hands and clothes should be prevented from being involved in the roll.
Three, stop attention
1. If abnormal sound is found in the operation of the machine tool, it should be stopped immediately for inspection, adjustment and repair.
2. Disconnect the switch and cut off the power supply.
3. Place the workpiece at the designated place after shutdown.