Used Machinery: Plate shears

Plate shears - This has nothing to do with chocolate

The plate shears or guillotine shears belong to the field of cutting manufacturing technology. As the name shears or scissors suggests, only the cutting of material is defined as a machining process.

Structure and functionality of plate shears

With the classic plate or guillotine shears, the cut is a straight cut. The structure and the mode of operation are usually carried out in a vertical construction. The main components of a guillotine shear are the plate table, guillotine shear frame, lower cutting beam with lower knife, upper cutting beam with upper knife, stops, hold-down device (blank- or downholder) and the drive. The drive is usually carried out by means of one or more hydraulic cylinders which move the upper cutting beam and the upper knife vertically up and down. The hydraulic cylinders can attack the upper cutting beam directly or the movement of the upper beam takes place via a toggle lever. The upper cutter beam is guided together with the knife in the frame of the guillotine shears.

The cut takes place at the moment when the upper knife passes the lower knife. The knives do not touch, but must be set to a defined gap. When cutting steel, the gap, also known as the cutting gap, must be approx. 10% of the material thickness to be cut with guillotine shears. The cutting gap varies from material to material. The quality of the cut can also be influenced by the cutting gap. The narrower the gap, the higher the cutting force required. The setting values given by the manufacturers are only recommendations and usually have to be optimized by the operators. The cutting gap becomes smaller and smaller as the material thickness of the material to be cut decreases. It can also go to zero, but it must be prevented that the knives overlap. Then knives breakouts cannot be avoided. From the paper scissors is known the effect that the cutting edges of the knives slide against each other during the cut.

The material to be cut is in a horizontal position between the upper and lower knife during the cut. Since the knives exert a torque on the material to be cut during the cut, a movement (rotation) must be absorbed. On the one hand, the material is supported on the shear table, on the other hand, a hold-down device prevents the material from being lifted off during the cut. The hold-down clamps the material positively during the cut.

The bottom knife of a guillotine shears is arranged horizontally. The upper knife is arranged at an angle. This incline is normally between 1 ° and 3 °. The more obliquely the knife of the guillotine shears is arranged, the lower the cutting force. But the stroke of the upper cutter beam to be carried out raises with the increase in the cutting angle. The risk of permanent deformation of the material to be cut after the cut also increases with the size of the cutting angle.

Another parameter for a right-angled cut is that the two knives do not move past one another in parallel, but rather that the upper knife is engaged by a clearance angle. A useful clearance angle is approx. 1.5 ° (for metals). The thicker the material to be cut, the more important it is to choose the right clearance angle for an rectangular cutting edge.

Wide range of plate shears and guillotine shears

In the metal sector, the guillotine shears for larger material thicknesses are equipped with hydraulic drives, as already described. Manually operated guillotine shears are also known from the paper and film sector. Pneumatic or electric drives are also conceivable with a somewhat higher expenditure of force.

For the processing of large and small workpieces, the plate and guillotine shears are available in different sizes and performance levels. One variant is the width, which can range from a knife length of 100 mm to widths over 10 m. The material thickness of the material to be cut ranges from a few micrometers to a thickness of over 200 mm. With short knife lengths and large material thicknesses, the guillotine shears mutate into billet shears or profile shears.

The variety of guillotine shears naturally also extends to the material. The most famous guillotine shears are those for metals, cardboard or plastics.

Other types of scissors, which in the broadest sense also work like plate shears, are:

Rotating and flying shears are used in cut-to-length lines for the cutting process.

The knives - the hard core of a pair of blades

Hardened and ground cutting edges are the characteristics of a knife. The material is a tool steel to achieve the necessary hardness. A good knife can be sharpened several times before it is completely worn out. The grinding can be done on normal surface grinding machines.

With us you will find a large selection of used plate shears

tramao offers you a large selection of used plate or guillotine shears. The plate shears in the metal category can be found in the metal cutting machines area.

You will find the right service companies for repairs and spare parts procurement on tramao.de.

You will also find a wide range of machine accessories on tramao. Not to be forgotten is our range of tools, including knives.

If you decide to buy used guillotine shears, you will find a large selection of well-known manufacturers such as Baykal, Durma, Safan, Haco, Digep, Fermat, Fasti or Matra on tramao.