| 1. |
Select the E-Vac type. |
| |
A. |
Determine if the part to be lifted is porous or non-porous. |
| |
B. |
Select a style - In-Line, Modular or Adjustable. The E-Vac type determines max. vacuum available for lifting the part and vacuum cup selection. |
| Porous |
low vacuum generators max. vacuum = 21" Hg (71 kPa) |
| Non-porous |
high vacuum generators max. vacuum = 27" Hg (91 kPa) |
| Adjustable E-Vac |
vacuum generators max. vacuum = 25" Hg (85 kPa) |
| 2. |
Determine the weight of the part. |
| 3. |
Multiply the weight by the vacuum cup safety factor for the total vacuum cup capacity needed. |
| 4. |
Determine the number of vacuum cups needed by considering the following: |
| |
A. |
How many cups are needed to distribute the weight for stable lifting and placement? |
| |
B. |
What is the weight that each vacuum cup can lift based on maximum vacuum available (E-Vac type)? |
| |
C. |
Select vacuum cups based on max. vacuum available (E-Vac type) and holding weight/cup. |
| 5. |
To choose an E-Vac model number, consider the entire vacuum system from the E-Vac to the part. |
| |
A. |
Number of vacuum cups per E-Vac |
| |
B. |
Length and size of vacuum tubing |
| |
C. |
Vacuum cup size and type |
- The volume of air to evacuate from your vacuum system and the vacuum flow of the E-Vac you've selected will determine the time it takes from E-Vac activation to vacuum cup holding the part. As the vacuum level in the system increases, the volume of evacuating air decreases.
- A lower volume of air in the vacuum system and/or a higher capacity (SCFM/SLPM) E-Vac will give faster pick-up times.
- An exact pick-up time cannot be calculated.
- If the E-Vac vacuum generator doesn’t meet your needs, return it for a different model, with no restocking charge.
Here is an example using the steps outlined above:
A sheet of material measures 3' x 3' (.91m x .91m) and weighs 25 lbs (11.3kg). Each sheet is in a stack and will be placed on a conveyor.
If it is porous like wood and positioned vertically:
| 1. |
Choose a porous, low vacuum E-Vac. In this case the Modular style will be used for easy mounting. The maximum vacuum is 21" Hg (71 kPa). |
| 2. |
The weight is 25 lbs (11.3kg). |
| 3. |
Since the part is picked-up and hung on an overhead conveyor vertically, the safety factor is 4. The vacuum cup capacity needed is 4 x 25 = 100 lbs (45.4kg). |
| 4. |
Four vacuum cups will be used for stability when lifting the sheet. Each cup will need at least a 25 lb (11.3kg) capacity. The Model 900755 Vacuum Cup will hold up to 25.3 lbs (11.5kg) at 21" Hg (71kPa). |
| 5. |
There are 4 small round vacuum cups that are positioned close to one another. The vacuum system has a small to medium volume and pick-up and release time is not critical. To reduce the sound level, use the straight through muffler. |
| Order: |
(1) Model 820008M Modular E-Vac; (4) Model 900755 Vacuum Cups |
If it is non-porous like glass and positioned horizontally:
| 1. |
Choose a non-porous, high vacuum E-Vac. In this case the Modular style will be used for easy mounting. The maximum vacuum is 27" Hg (91 kPa). |
| 2. |
The weight is 25 lbs (11.3kg). |
| 3. |
Since the part is picked-up and placed on a belt conveyor horizontally, the safety factor is 2. The vacuum cup capacity needed is 2 x 25 = 50 lbs (22.7kg). |
| 4. |
Four vacuum cups will be used for stability when lifting the sheet. Each cup will need at least a 12.5 lb (5.7kg) capacity. The Model 900754 Vacuum Cup will hold up to 20.8 lbs (9.4kg) at 27" Hg (91 kPa). |
| 5. |
There are 4 small round vacuum cups that are positioned close to one another. The vacuum system has a small to medium volume and pick-up and release time is not critical. To reduce the sound level, use the straight through muffler. |
| Order: |
(1) Model 830006M Modular E-Vac; (4) Model 900754 Vacuum Cups |
NOTE:
The Model 840008M Adjustable E-Vac can be substituted for picking up the wood or the glass since the vacuum level and vacuum flow is easily adjusted to suit the porous or non-porous application. The Adjustable E-Vac is especially useful for loads that vary.