Cutting Presses

A cutting press is a type of machine used for cuttingpushes it through the die. This results in obtaining the
and forming material. It may be a large CNC operatedrequired shape of the punch and die set. The piece
machine and hold a large or small complex die set, orof material that is pushed through the die by the
it may be small and manually operated and hold onlypunch will then be collected underneath the machine.
a single simple die.Depending on the application, the pushed out formed
Press cutting machines are large metal framed andmaterial may be the desired component, or the
will have some type of ram in the upper part to allowformed hole made by the punch may be the desired
the cutting or punching process to be carried out.result.
Most cutting presses will have a table or bed withMost of todays punch presses are hydraulically
rollers or brushes mounted in the tables to enable thepowered, but there are still older mechanically driven
sheet metal workpiece to move with low friction.machines in use. These mechanical machines are
Brushes are very often used to minimalise scratchingpowered by a constantly rotating flywheel which in
to the workpiece and this is important when workingturn drives a ram to which the punch is attached.
with sheet metals such as highly polished steels orThe flywheel is powered by a large electric motor.
brushed aluminium.Hydraulic presses power the ram with a hydraulic
A punch press is a machine which is used forcylinder and are either valve and feedback controlled
processing sheet materials such as sheets ofor just valve controlled. Valve controlled machines
aluminium or sheets of mild steel etc. The machinehave a one stroke operation which enables the ram
performs the cutting operation; stamping or formingto stroke up and down. Systems that use controlled
at specified sites co-ordinated by data. These typesfeedbacks enable the ram to be proportionally
of machines are usually computer controlled (CNC)controlled to within fixed points. Controlled feedback
and enables automatic mode by the use of a pre-builtsystems allow better control over the stroke of the
program.ram; punching rates are increased because the ram
Punch presses are used for high volume productiondoes not have to complete the full stroke up and
and is a very efficient metal forming process. Thedown, and can work more efficiently with a very
punch is positioned above the die which is held inshort stroke.
place below it. The punch enters the material and