Suction Cup Selection

The calculated theoretical holding force corresponds to the force that the suction cups must create to handle the workpiece safely. To select the suction cups, one must also take the ambient conditions and the application into consideration. The selection of the suction cups usually takes place based on the following criteria:

Suction cup from different product lines

Application: Multi-shift operation, service life, chemically aggressive environment, temperature, etc.

Material: Suction cups made of different materials are available to meet the requirements, such as those particularly suited for smooth or rough surfaces, oily or very fragile workpieces, anti- static suction cups for electronic components, suction cups leaving few marks for fragile plastic parts, etc.

Surface: Depending on the condition of the surface, we recommend suction cups in specific shapes. You can select from flat or bellows suction cups with different sealing lips and sealing edges in different shapes and geometries.

For this example we choose:

Flat suction cup of the type PFYN made of Perbunan NBR

This suction cup is a cost-efficient solution for handling smooth, level workpieces.

To solve the example, the calculated theoretical holding force can be applied by one suction cup or distributed among several suction cups. The number of suctions cups used depends on the respective application.

For the steel sheet (2,500 x 1,250 mm) from the present case, one would usually use six or eight suction cups. The most important criterion for the number of suction cups in this example, is the flexing of the steel sheet during transport. Depending on the number of used suction cups, the required diameter of these suction cups changes.

Calculation of suction force FS [N] for individual suction cup

FS = FTH /n

FS = Suction force

FTH  = Theoretical holding force

n = Number of suction cups

Our example:

FSc  = 1,822 N / 6

F = 304 N

According to the technical data for the suction cup PFYN, one needs 6 x PFYN 95 NBR with a diameter of 95 mm and a suction force of 350 N each.

FS = 1,822 N / 8

FS = 228 N

According to the technical data for the suction cup PFYN, one needs 8 x PFYN 80 NBR with a diameter of 80 mm and a suction force of 260 N each.

For this example we choose:

Six suction cups of type PFYN 95 NBR
With a sheet thickness of 2.5 mm, six suction cups ensure a secure sheet pick


  • The suction force of the individual suction cups is listed in the technical data and must exceed the calculated theoretical holding force.