Press Tools

Punching machine die is the “accessory” corresponding to the punch. The workpiece undergoes plastic deformation under the combined action of the punch of the punch and the resistance of the die to complete the processing process. The punch die is an indispensable part of the stamping process, and the accuracy of the punch die is largely determined Improve the machining accuracy of the workpiece.

Structure description

The die on the punch is the upper half of the entire die, that is, the die part installed on the slider of the press. The upper die seat is the uppermost plate-shaped part of the upper die. When the workpiece is close to the press slider, it is fixed by the die handle or directly with the press slider. The lower die is the lower half of the whole set of die, that is, the die part installed on the working table of the press. The lower mold base is a plate-shaped part on the bottom surface of the lower mold, which is directly fixed on the working table or backing plate of the press when working. The blade wall is the side wall of the cutting edge of the punching die hole. The slope of the cutting edge is the slope of each side of the wall of the punching die hole. The air cushion is a bomb ejector with compressed air as the driving force. Refer to “Topper”. The opposite side pressure block is a part that supports the one-way force-bearing punch from the other side of the working surface.

Punch guide sleeves are tubular parts that provide precise guidance for the relative movement of the upper and lower mold bases. Most of them are fixed in the upper mold base and used in conjunction with the guide posts fixed on the lower mold base. The guide plate is a plate-shaped part with an inner hole that is precisely slid and matched with the convex mold. It is used to ensure the mutual alignment of the convex mold and the concave mold, and plays the role of unloading (piece). The guide post is a cylindrical part that provides precise guidance for the relative movement of the upper and lower mold bases. Most of them are fixed on the lower mold base and used in conjunction with the guide sleeve fixed on the upper mold base. The guide pin is a pin-shaped part that extends into the material hole to guide its position in the cavity. The guide plate mold is a die guided by the guide plate, and the punch does not leave the guide plate when the mold is used. The guide plate is a plate-shaped guide part that guides the strip (belt, coil) into the die. The guide pillar mold base is a mold base in which the guide pillar and the guide sleeve slide mutually.

Instructions

Punch die is a process equipment installed on a press to produce punches, and it is composed of an upper and a lower part that cooperate with each other. A punch is a convex working part that directly forms a punch in the punch, that is, a part whose shape is the working surface. The concave die is a concave working part that directly forms a punch in the die, that is, the part whose inner shape is the working surface. The protective plate is a plate-shaped part that prevents fingers or foreign objects from entering the dangerous area of ​​the die. The press plate (ring) is a part used in the die to press the stamping material or process parts to control the flow of the material. In the deep drawing die, the press plate is mostly called the press ring. The press bar is a rib-like protrusion used to control the flow of the material in the drawing die or the drawing die. The press bar can be the partial structure of the die or the press ring, or it can be embedded in the die or the press ring. Separate parts. The pressure bar is a special name for the pressure bar with a rectangular cross-section. Refer to “Pressing bar”. The bearing plate is a plate-shaped part used to connect the upper plane of the long concave die and support the stamping material. The continuous die is a die with two or more stations, and the material is sent to one station one by one along with the stroke of the press, so that the stamped parts are gradually formed.

The side edge of the punch is a punch that cuts out the feeding positioning gap on the side of the strip (belt, roll). The side pressure plate is a plate-shaped part that exerts pressure on one side of the strip (belt, coil) through a spring to make the other side abut the guide plate. The ejector rod is a rod-shaped part that directly or indirectly ejects the work (sequence) or the order material with an upward movement. The top plate is a plate-shaped part that moves in the die or module, and directly or indirectly ejects work (sequence) parts or waste materials with an upward movement. The ring gear is a ring-forming tooth-shaped protrusion on a fine-blanking die or a toothed pressing plate, which is a partial structure of the concave die or a toothed pressing plate, rather than a separate part. The limit sleeve is a tubular part used to limit the minimum closing height of the die, and is generally sleeved outside the guide post. The limiting column is a column-shaped part that limits the minimum closing height of the die. Locating pins (plates) are parts that ensure that the process parts have a constant position in the mold. They are called locating pins or locating plates due to their different shapes.

The punch fixing plate is a plate-shaped part that fixes the punch. The fixed unloading plate is a unmoving plate fixed on the die. The fixed stopper pin (plate) is a stopper pin that is fixed in the mold. The unloader is a non-plate-shaped part or device that unloads the work (sequence) from the outer surface of the punch. The unloading plate is a fixed or movable plate-shaped part that unloads materials or work (sequence) parts from the punch. The discharge plate is sometimes made into a whole with the guide plate, and also serves as a guide, and is still called the discharge plate. The unloading screw is a screw fixed on the elastic unloading plate, which is used to limit the static position of the elastic unloading plate.

The sheet punching process die is a die that only completes one process in one stroke of the press. There are two types of scrap cutters:1. A cutter installed on the flange trimming die of the drawn part to cut off the entire circle of trimming waste to facilitate removal. 2. A cutter installed on a press or mold to cut strip (belt, roll) waste to a fixed length to facilitate removal. Combined punching die is a universal and adjustable complete set of punching dies that gradually form various punching parts according to geometric elements (straight lines, angles, arcs, holes). The contour of the plane-shaped punching part generally needs several sets of combined punching dies to be punched in stages. The starting stopper pin (plate) is a part used for positioning when the starting end of the material is fed. The first stopper pins (plates) are all movable. Blocks are the individual parts that make up a complete die, punch, discharge plate or fixed plate. The stopper (plate) is a hardened part used for positioning when the material cut by the side edge cuts the gap when it is fed, and it is also used to balance the single-sided cutting force experienced by the side edge. The stop (plate) is generally used in conjunction with the side edge.

maintenance

1. Ensure the best mold gap. The mold gap refers to the sum of the gaps on both sides of the punch entering the lower mold. Different plate thicknesses and different materials should be used for lower molds with different clearances. Choosing a suitable mold gap can ensure good punching quality, reduce burrs and collapse, keep the sheet flat, effectively prevent stripping, and extend the life of the mold.

2. Timely sharpening can effectively extend the service life of the mold. When the edge of the mold wears and produces an arc with a radius of about 0.10 mm, sharpening is required. When sharpening, the grinding amount is 0.03~0.05mm each time, and the grinding is repeated until the punch is sharp. After sharpening, polish the cutting edge with oil stone to remove burrs, and apply lubricating oil after demagnetization treatment.

3. Regularly check the alignment of the upper and lower mold bases of the turntable. If the centering of the punch die position is not good, the die will be quickly passivated and the quality of the workpiece will deteriorate. Check and lubricate the die holes and guide keys on the turntable, and repair them in time if damaged; clean the lower die seat of the turntable so that the lower die can be installed accurately, and check the wear of its keys or key grooves, and replace them if necessary; use special mandrels Calibrate the mold station and adjust in time if there is any deviation.

4. When punching soft or viscous materials (such as aluminum); punching thin abrasive materials (such as glass epoxy sheet); punching thin hard materials (such as stainless steel); frequently nibbling, you can use surface hardening (using plating Titanium, nitriding and other methods, the surface hardened layer is a punch with a molecular structure with a thickness of 12 to 60 μm.

5. The molding die should be fine-tuned upwards from the lowest position to the appropriate position, otherwise the die will be easily broken.

6. ​​Due to the pressure and heat during punching, the small particles of the sheet will be bonded to the surface of the punch, resulting in poor punching quality. It can be polished with fine oilstone to remove the sticky material, and the polishing direction should be the same as that of the punch.

7. If you punch a lot of holes on a board, you should punch every other hole first, and then return to punch the remaining holes, which can effectively alleviate the stress accumulation during sequential punching in the same direction, and it will also make the front and back two sets of holes The stresses cancel each other out, thereby reducing the deformation of the sheet.

8. Try to avoid punching too narrow strips. When the die is used to punch a sheet with a width less than the thickness of the sheet, the punch will bend and deform due to lateral force, which will make the gap on one side too small or aggravate the wear. In severe cases, the lower die will be scratched and the upper and lower dies will be scratched. Damaged at the same time.