Glossary

Stroke Control - The ram travel of the press may be controlled in a variety of ways. Most hydraulic presses are standard with Adjustable Retract Limit Switches to limit the retract distance of the ram (also know as the Up Limit Position). This can shorten cycle times by only utilizing the required stroke for part loading and unloading. Other adjustable limits may include: Slow Down Limit for deceleration from Fast Speed to Slow Speed; Bottom Stop Position and/or Bottom Stop Pressure etc.

Shut Height - The distance between the bed bolster & the raw bolster when the raw is fully extended. This is also known as closed Height.

Stroke - The amount of possible ram travel. Stroke is the total distance that the ram can travel, from full extension to full retraction.

Shut Height - The distance between the bed bolster and the ram bolster when the ram is fully extended. This is also commonly known as the Closed Height. As standard, this dimension is usually within "0.25" due to assembly processes. For precision shut height requirements, consult the factory.

Scuffing - A wear mechanism involving microwelding of asperities on contacting surfaces under conditions of highloading and high relative velocities. This microwelding is normally followed by rupture of the welds, roughening and increasing friction.

Slab Side Hydraulic Press or Straight Side Hydraulic Press - Typically this style of hydraulic press uses solid side construction to guide press and platen operation in larger applications. Slab style construction keeps press components properly aligned, within specified tolerances, and minimizes deflection.

Throat Clearance - The distance from the vertical centerline of the ram to the frame member behind the bed. This distance determines the largest diameter piece that can be positioned with the part centerline under the center of the ram.

Thermal Stability - A measure of the chemical stability of a fluid subjected to high temperatures and includes resistance to molecular scission or cracking. For hydraulic fluids, this property is principally a criterion for the stability of additives.

Thin-film Lubrication - A condition in which the film thickness of the lubricant is such that the friction between the surfaces is determined by the properties of the surfaces as well as the viscosity of the lubricant.

Tribology - The science and technology of friction, lubrication and wear. Officially known as the study of interacting surfaces in relative motion and all related engineering problems including the subjects and practices of friction, lubrication, and wear.

Trunnion - A pair of short journals supported in bearings projecting coaxially from opposite sides of a component required to pivot about their axis.