## Guide to Vacuum Pump Selection by Vaccon

**Pick and Place - Material Handling**

Referred to here as the lifting, gripping, rotating and positioning of an object through the use of a vacuum pump and vacuum cup.

Use the equation: Force = Pressure x Area to determine:

1. Lifting capacity of the pump and cup, 2. Required vacuum area, i.e. diameter of cup, 3. Required vacuum level of vacuum pump.WHERE:

- F is the weight of the object in pounds (lbs) multiplied by a safety factor. 2x - Horizontal cup position. 4x - Vertical cup position.
- P is the expected vacuum level in PSI, remember to convert "Hg" to PSI by dividing by 2
- A is the area of the vacuum cup in sq. inches.
- Use the equation, Area = 2 Vacuum Level Ranges - High Vacuum and Medium Vacuum
- "H" - Series (28" Hg) for non-porous materials to generate maximum holding force.
Hint: Try P = 12.5 PSI (25" Hg) as a starting value when using equation, F = P x A.

- "M" - Series (20" Hg) for porous materials to generate medium holding force while overcoming leakage and saving compressed air.
Hint: Try P = 8 PSI (16" Hg) as a starting value when using equation, F = P x A.

Cycle rate of the pump and cup system is determined by the evacuation speed of the venturi, see "Vessel Evacuation" below.

INEXACT SCIENCE

When handling porous materials such as corrugated or heavy fabric it is hard to choose the exact pump required because the leakage rate is not normally known. Therefore, it is best to run a bench top trial to test the ability of the pump to overcome the leakage. For existing systems, consult Vaccon for the equivalent pump size. In new applications, take advantage of Vaccon's free 30 day trial to ensure proper pump selection

Increase safety, reliability and speed by using one small FASTVAC pump at each cup location. Should one cup fail the others will not be affected.

VESSEL EVACUATION

In many process applications it is necessary to evacuate a vessel for the purpose of purging gases, leak testing, or degassing viscous fluids. Other times the vessel may simply be the length of tubing between the pump and cup. Knowing the evacuation speed will help determine process completion time or the production rate of a pick and place system.

Evacuation speed is directly related to the vacuum flow of the pump. To use the chart of evacuation speed listed in the catalog for each venturi, identify the following operating conditions;

1. Volume to be evacuated (Cu. Ft.), 1728 cu, in. = 1 cu. ft. 2. Desired vacuum level ("Hg), 3. Time to reach vacuum level (seconds).

Note: The charts in the catalog are based on a one cubic foot volume. Evacuation speed is linear with volume, therefore a 2 cu. ft. volume will take twice as long to evacuate