Machine press

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File:Power press animation.gif
Power press with a fixed barrier guard

A machine press, commonly shortened to press, is a machine tool that changes the shape of a workpiece.[1]

Types

Drives

Hydraulic

Servomechanism

A servomechanism press, also known as a servo press or a 'electro press, is a press driven by an AC servo motor. The torque produced is converted to a linear force via a ball screw. Pressure and position are controlled though a load cell and an encoder. The main advantage of a servo press is its low energy consumption; its only 10-20% of other press machines. Another advantage is a quiet and clean work environment.

Arbor press

Forging press

A forging press reforms the work piece into a three dimensional object—not only changing its visible shape but also the internal structure of the material. A stronger part results from this process than if the object was machined.

Press brake

A press brake is a special type of machine press that bends sheet metal into shape. A good example of the type of work a press brake can do is the backplate of a computer case. Other examples include brackets, frame pieces and electronic enclosures just to name a few. Some press brakes have CNC controls and can form parts with accuracy to a fraction of a millimetre. Bending forces can exceed 4,000 kilonewtons (900,000 lbf).[citation needed]

Punch press

A punch press is used to form holes.

Quench press

Rolling press

A rolling press has a set of rollers used to thin sheet metal. The sheet metal is fed into the rollers, which are turning, and the sheet is pulled through. The space between the rollers is smaller than the starting sheet metal thickness, therefore the metal is made thinner and/or wider.

Screw press

A screw press is also known as a fly press.

Stamping press

Others

Another kind of press is a set of plates with a relief, or depth-based design, in them. The metal is placed between the plates, and the plates are pressed up against each other, deforming the metal in the desired fashion. This may be coining or embossing or forming.

Capping presses form caps from rolls of aluminium foil at up to 660 per minute.

Comparison

Comparison of various machine presses
Type of press Type of frame Position of frame Action Method of actuation Type of drive Suspension Ram Bed
Open-back Gap Straight-side Arch Piller Solid Tie rod Vertical Horizontal Inclinable Inclined Single Double Triple Crank Front-to-back crank Eccentric Toggle Screw Cam Rack & pinion Piston Over direct Geared, overdrive Under direct Geared, underdrive One-point Two-point Four-point Single Multiple Solid Open Adjustable
Bench X X X X X X X X X X X X X X X X X X
Open-back inclinable X X X X X X X X X X X X X X X X X X
Gap-frame X X X X X X X X X X X X X X X X X X X X X X X X
Adjustable-bed horn X X X X X X X X X X X X X X X
End-wheel X X X X X X X X X X X X
Arch-frame X X X X X X X X X X X X
Straight-side X X X X X X X X X X X X X X X X X X X X X X X X X X
Reducing X X X X X X X X X X X X X X X
Knuckle-lever
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Toggle-draw
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Cam-drawing
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Two-point single-action
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
High-production
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Dying machine
X
X
X
X
X
X
X
X
X
X
Transfer
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Flat-edge trimming
X
X
X
X
X
X
X
X
Hydraulic
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Press brake
X
X
X
X
X
X
X
X
X
X
X
X

History

Historically, metal was shaped by hand using a hammer. Later, larger hammers were constructed to press more metal at once, or to press thicker materials. Often a smith would employ a helper or apprentice to swing the sledgehammer while the smith concentrated on positioning the workpiece. Adding windmill or steam power yielded still larger hammers such as steam hammers. Most modern machine presses use a combination of electric motors and hydraulics to achieve the necessary pressure. Along with the evolution of presses came the evolution of the dies used within them.

Safety

Machine presses can be hazardous, so safety measures must always be taken. Bi-manual controls (controls the use of which requires both hands to be on the buttons to operate) are a very good way to prevent accidents, as are light sensors that keep the machine from working if the operator is in range of the die.

References

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External links

ar:مكبس (آلة تشكيل)

az:Pressləmə ca:Premsa mecànica cs:Lis de:Presse (Maschine) es:Troquelación eo:Premilo it:Pressa hu:Mechanikus sajtók nl:Pers (machine) ja:プレス機械 no:Stanse ru:Пресс (механизм) sv:Pressning (industri)

uk:Прес
  1. Press, retrieved 2009-11-24.