Vacuum Glossary

The abrasion resistance refers to the resistance of suction pads (elastomer part) against mechanical stress, especially friction. It is determined by the material properties of the suction pad, as well as its shape.

The absolute pressure refers to the absolute zero point, or a space completely empty of molecules. In an absolute vacuum there is a pressure of 0 bar. A relative vacuum of -600 mbar corresponds to an absolute pressure of 400 mbar.

Ambient pressure refers to the hydrostatic pressure that exists at any given point. Ambient pressure is also known as atmospheric pressure. The standard atmospheric pressure at sea level is 1,013 mbar. The ambient pressure drops with increasing altitude. The ambient pressure has a direct influence on the maximum vacuum value that can be reached. The ambient pressure at any altitiude can be roughly estimated with the vacuum level calculator.
Vacuum Level Calculator

The check valve is the valve that automatically monitors volume flow. If the volume flow exceeds a defined value, the valve closes automatically.

The control pressure range is the range between the lowest and highest permissible control pressures.

The cycle time refers to the time taken for a repetitive process to complete one cycle.

Flow resistance refers to a reduced flow cross-section in a vacuum line. The resistance reduces the volume flow that can pass through a line.

A high vacuum describes any vacuum in which there is an absolute pressure of 10⁻⁷ to 10⁻³ mbar. High vacuums are used for particle accelerators.

Holding force refers to the force that can be exerted by a suction pad to grip a workpiece. It is calculated by multiplying the pressure difference by the effective suction area of the suction pad (F= Δp x A). The holding force of a suction pad is thus influenced by underpressure and the suction area. It is a theoretical value, specified without safety factors. It is usual to state the holding force of a suction pad with a relative vacuum of 60%. The mass of the workpiece can be calculated with the vacuum cup lifting capacity calculator.
Vacuum Cup Lifting Capacity

The NO valve refers to the position of the valve when it is not actuated, i.e. "open" (normally open).

Leakage refers to a leak within the vacuum system. This can be caused by missing or faulty sealing elements, or by the porosity of the workpiece being processed.

A low vacuum describes any vacuum in which there is an absolute pressure of 1 mbar up to atmospheric pressure (1,013 mbar). Examples of applications for a low vacuum include light bulbs and vacuum cleaners. Vacuum handling technology also uses values in the low vacuum range because these can be generated economically to create high suction power and short cycle times.

NPN switching output refers to the configuration of a switching output in cases where the load is connected to the positive pole of the operating voltage source. The output transistor of the vacuum switch connects the active device through to the operating voltage, allowing current to flow through the consuming device.

PNP switching output refers to the configuration of a switching output in cases where the load has a permanent connection to the operating voltage source. The output transistor of the vacuum switch connects the active device to the positive pole, allowing current to flow through the consuming device.

Shear force is the force acting tangentially to a surface and indicates how much friction can be transferred between the suction pad and workpiece. Shear force is given in Newton (N).

Suction rate refers to the suction power of a vacuum generator. This value indicates the volume that can be evacuated by a vacuum generator in a certain time. The suction rate is given in l/min or m³/h.

A vacuum is a pressure range lower than that of the ambient pressure. The vacuum value is divided into various classes; refer to "High Vacuum" and "Low Vacuum".

Volume flow refers to the volume of a medium that flows through a cross section within a certain amount of time. Volume flow is given in l/min or m³/h.

The workpiece temperature is the temperature of a processed workpiece. The temperature can influence the selection of a suitable suction pad material.