Development Trend of Forming Machine
Forming machine is a kind of high-performance forging equipment which shears and plasticizes coils and can produce hundreds of bolts per minute. According to the different structure of forging die, various parts and screw blanks can be produced. In this paper, the structure and characteristics of the forming machine, which is a piece of indispensable equipment in the bolt manufacturing process, are described, and the latest functions and development trends of the forming machine are introduced. In recent years, there are two technologies deserving special attention in the forming process: one is to change the preparation process and improve the operation rate technology; the other is high-precision forming technology.
Forming machine is a kind of horizontal press, which is mainly driven by a crank mechanism. The forming machine cuts the material, i.e. coil or bar, into a specified length, and then clamps the blank between the fixed forging die (cavity block) and the movable forging dies (force piston) for forming. It is mainly used for cold heading and hot heading of bolts, rivets, and components.
The forming machine is composed of a transmission device, feeding device, shearing device, forging and pressing device, pushing device and conveying device. The main driving device is the main generator, which transfers power to the transmission mechanism. It regularly drives gears and cams through pneumatic clutches.
In recent years, the forming machine has been converted to the production of large components with special shape and high added value. There are two points deserving special attention in production, one is to change the preparation process and improve the rate of operation technology; the other is high-precision forming technology.
Replacement of Preparatory Procedures and Improvement of Operating Rate Technology
Straightener with dicephalic drawbench
About 30% of large-scale and long-size products are made of wire. Therefore, it is very important to supply wire varieties in time because of the high frequency of replacement. Straightener with dicephaly drawbench is different from straightener used in production.，It is a straightener parallel to a straightener used as standby. In the process of forming, it can load wire, straighten the bending part, and make preparations for supplying wire for the forming machine. When the wire is used up in production, as long as it is replaced by a straightener loaded with the next production wire, the preparation process for wire replacement can be completed, which greatly shortens the replacement time.
Integral Replacement System of Forging Die Device
The whole replacement system of forging die device uses hydraulic cylinder to fix the negative die and the positive die for clamping the forging die, so the button can be used for switch operation in the replacement preparation process. Because the forging die device can be replaced entirely by the special driving vehicle or robot in the workshop, the preparation time for replacement can be shortened.
Elevating gear of cavity block
In general, there are more than two cavity blocks for large forging dies. In order to lift cavity block in the forging die machine, because of the fear that the negative die will be scratched by the frame, the lifting operation of the cavity block should be cautious and difficult. Using the lifting device of the cavity block, the lifting operation of the cavity block can be simplified, and the device of the cavity block can be lifted to a fixed position by using a hydraulic cylinder.
Self-correcting of the front and rear position of the force piston
The processing temperature of forging die changes with the change of processing time, which will lead to the change of product size. In order to correct this change, an effective way is to set up an electric automatic adjusting device for the position of the front and back of the force piston. In the past, this kind of remedial operation needs to stop the forming machine first, and then the operator enters the machine to adjust the position of the force piston. Because of the development of automatic adjustment device, it can be adjusted in the process of equipment operation. It can also solve the influence of high temperature in the initial stage of equipment operation on product size change, effectively improve productivity and reduce the incidence of undesirable products.
Turning over of conveyor frame and pulling out of inner core
When the conveyor rack rises from the running position, it turns to the operator's side and the conveyor is aimed at the operator. Therefore, it is helpful for the replacement of the manipulator and the adjustment of the core pull-out. At the same time, it can ensure that there is a large space inside the forging device, thus improving the operability.
High Precision Molding and Quality Assurance
Orthoscopic feeder unit
Common feeding machines use feeding rollers to feed materials. When the materials touch the block, they can be cut to a specified length. At this time, due to friction between the material and the block, sometimes the material will be scratched and other bad conditions. In order to prevent this phenomenon, a straight-line feeding device is installed, which uses straight-line clamp to clamp material into forging equipment. Because there is no sliding between the material and the clamp, high precision shearing can be achieved even without the block.
Punching shear device
When the blank is sheared, because the shearing method is adopted, the shearing inclination will occur and the shearing right angle with good end face cannot be obtained. Increasing the shear speed can improve the sheared edge. In the initial stage of shearing process, the cutter of common shearing machine accelerates at zero velocity and shears at the same time. idling stopping distance is set before the punching shear, and the shearing process begins at the end of the acceleration stage. Therefore, it can obtain about 2m/s shear speed and obtain good blank end face.
Gapless extrusion rod device
In order to produce high precision products, it is very important to ensure the accuracy of core deviation to ensure the accuracy of inner and outer diameters of products. Because the extrusion rod is formed by the reciprocating movement of the force piston, the sliding surface must have clearance. This gap will affect the accuracy of the product. Therefore, the accuracy of core deviation can be improved by using roller bearings to slide the sliding surface and making the clearance between the extrusion rod and the sliding surface zero.
SP Conveyor Belt to Prevent Injury
The forming machine is a horizontal forging press. In the final forming process, the blank separated from the die will fall freely on the chute at the lower part of the forging and pressing part. Scratches on falling billet will affect product quality. To solve this problem, the SP conveyor belt is developed, which opens through holes on the frame and extends the product discharge conveyor belt below the final conveyor position. Because the product landed soft on the SP conveyor belt under the conveyor manipulator, there were no scratches on the blank.
