Laboratory Press: Complete Guide to Types, Applications & Selection

 


What Is a Laboratory Press?

A laboratory press is a miniature version of an industrial press. Lab press is a bench-top or floor-standing machine which primarily applies a progressively increasing compressive force to a material sample.
The force can shape the material. Prepare the material for testing or use it to craft patterns or study a material’s response to force.
Any laboratory press has three main components:
  • Frame:  resists the reaction force
  • Platens: platens are plates or components that make contact with the sample or mold
  • Force mechanism: how the force is generated, which depends on the hydraulic or motor press.

How Hydraulic Force Is Generated

The most common type of lab press is the hydraulic press, which works on a very simple pressure law. When pressure is applied to an incompressible fluid (oil), it is transmitted equally in all directions throughout the fluid.
In a lab press, a small pump piston is used to move the hydraulic fluid into a larger cylinder cavity. You can guess the force output at the ram will be higher because pressure is constant across the system, and the ram area is larger than the pump piston area.
This ratio can be adjusted by changing the size of the RAM, cylinder, or piston. For example, an area ratio of 10:1 means a 100 kg input force can turn into 1000 Kg at the ram.

Core Types of Laboratory Press

Manual Hydraulic Laboratory Press
The manual hydraulic lab press uses a hand lever pump, which builds pressure. The machine is dependent on user inputs and controls through analog dials. It has no motor or electronic control and is a purely mechanical press.
The machine is limited to 25 tonnes press capacity and is unreliable in applications that require repeatability and controlled parameters. It is not recommended for cycle-to-cycle production.
Automatic Hydraulic Lab Press
Automatic lab presses like the FYI Laboratory Press use an electric motor-driven hydraulic unit. You can pre-set the load, dwell time, and program instructions into the lab press for a multi-step rubber lab press cycle. It has a PLC that controls the valve, which is used to maintain pressure or release pressure within a very tight pressure tolerance.
This removes variability and non-standard tests that would come from manual inputs and experimental variance. Autmotaic lab presses are the standard choice because they can be used by multiple operators and provide micro control over the parameters.
Pellet Press / KBr Press
Pellet presses are much smaller hydraulic presses that are specifically designed for the purpose of forming solid pellets from a powder. The most common use of these lab presses is to experiment or produce KBr discs for spectroscopy.
Heated Platen (Hot) Press
Heated platen or a heat press has an electric heating unit in the plate, which is thermally adjusted to apply heat and force to the rubber mold simultaneously. These types of lab presses are useful for thermoplastics, elastomers, and rubber materials.
The temperature is controlled and checked automatically using a PID controller, which can set and correct the temperature with an accuracy of up to 0.5°C. Water-cooled platens are also an option, but only needed when you need fast quenching rates post-molding, for example, for ASTM D4703 standards.

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