Metalworking Is Literally a High-Pressure Business

You watch as a seasoned blacksmith takes a piece of red-hot iron with tongs out of the forge and lays it on his anvil. He picks up his heavy hammer and starts to beat the metal into a shape. You marvel at the skill of this craftsman in shaping the metal to his will, perhaps comparing him to a sculptor. While that is an apt analogy, what you are witnessing is also one of the most ancient examples of what is essentially a stamping press in action—heavy downward force applied to a malleable workpiece that is positioned on an immovable surface.

The use of pressure to deform metal is the most basic example of metal fabrication and has application in several machines found in the typical shop. Brakes, shears, punches, and other tools use the principle of pressing—often at high speeds—to do their work.

The traditional metalworking press—a machine that utilizes platens or tooling to flatten or shape metal workpieces under pressure—is a mainstay of metalworkers of every level, whether they just have a small shop press tucked in a corner for occasional projects or a massive hydraulically powered machine located front and center for everyday use.

A Brief History of Presses

One of the earliest tools known to humans is the press. The idea that pressure—applied either through human force or through gravity—combined with two hard surfaces could flatten, crush, or otherwise transform an object between those surfaces goes back to the first time a rock was used to crack open a nut against another rock. As woodworking, stone working and eventually metalworking advanced, the use of two flat plates that could press an object between them while mounted in some sort of mechanism has been a constant in production work the world over.

Power sources for presses over the millennia have taken a variety of forms, including:

  • Human muscle strength directly applied
  • Gravity, by using weights
  • Levers to intensify muscle strength
  • Screw mechanisms
  • Steam power
  • Electric motor driven
  • Hydraulic power

The pinnacle of press power sources, hydraulic, offers the advantages of producing higher amounts of force, distributing that force uniformly across the platen, and allowing a slower ram speed during the actual forming than throughout the rest of the operation for better control and less chance of damage to the workpiece.

Along with just squeezing or flattening a workpiece, press developers over the centuries have introduced non-flat tooling into use with press mechanisms for such functions as printing paper, embossing different materials with a design, punching holes, or cold forging parts. The concept of the press brake is simply the application of a powered press combined with a metal-bending brake.

Types of Metalworking Presses

Presses can be classified in several ways, from function to power source to frame type. Here are some of the designations of presses that are used in metalworking:

  • 4-post press (same as a column press)
  • Air or pneumatic press
  • Arch press
  • Bench-mounted press
  • Bending press
  • Blanking press (hydraulic for thicker materials)
  • C-frame press or C press (also called a gap frame press)
  • Clinching press
  • Coining press
  • Column press, also called a 4-post press or a straight-side press
  • Crank-driven press
  • Cutting or shearing press
  • Deep drawing press (hydraulic)
  • Die-cutting press
  • Double reduction gear type press (electric) 
  • Double-action press
  • Electric-driven press
  • Embossing press
  • Extruding press (hydraulic)
  • Fine blanking press
  • Flattening press (same as a straightening press)
  • Fly press (manually operated)
  • Forging press
  • Forming press
  • Gap press or gap-frame press (same as a C-frame press)
  • Gear-type press
  • H-frame press
  • Horn press
  • Hot plated press
  • Hydraulic-driven press
  • Inclinable press
  • Inclined press
  • Manual press
  • Marking press
  • Mechanical press
  • Multi-station press (same as a rotary turret press)
  • Multiple reduction gear type press (electric) 
  • Multiple-action press
  • Non-geared, fly wheel type press (electric)
  • Open back press: OBI (inclinable) or OBS (stationary) 
  • Piercing press or hole-punching press (hydraulic)
  • Portal press
  • Punch press
  • Rack and pinion-driven press
  • Rotary turret press (same as a multi-station press)
  • Servo-driven (or servo control) press
  • Shop press
  • Side punching (notching) press
  • Single-action press
  • Single-reduction gear-type press (electric) 
  • Sliding bed or roll frame press
  • Stamping press
  • Straight-side press (same as a column press)
  • Straightening press (same as a flattening press)
  • Triple-acting press
  • Workshop press


Finding the Right Press for Your Application

Some questions to ask when shopping for a press include:

  • What is the maximum pressure needed for my applications?
  • What is the size of my largest potential work piece?
  • How often will I need to use the press?

These simple questions can help determine whether you can get by with a manually operated press, need to purchase an air or electric press, or must acquire a hydraulic press for your operation.

Be sure to look at all options carefully and talk to qualified—and trusted—press distributors to get the best idea of what press you need for your shop or plant.