ANVER Vacuum Cups and Suction Cups Model: Small Oval Cup with SnapOn Reusable Fittings Part Number: OC1030NBR Notes: The cup capacities shown above ( * ) are based on 24″Hg at sea level with a safety factor of two (2). This is the US ANSI ASME Standard B30.20 for vacuum lifter specifications and is commonly used in North America as a design capacity for vacuum components. When used in vertical applications, take these values and divide again by 2 to obtain a 4 to 1 safety factor per the ANSI specifications. These are realistic working capacities when designing equipment. Other manufacturers use a pulloff figure at 27″Hg to show a high capacity value for their cups. This is accurate, but requires users to do all the math themselves to build in safety factors. The values are basically the same, but it is necessary to calculate the working capacities with a safety factor via the following formula at sea level:
Pulloff value (at 27″Hg) = ANVER’s Listed Capacity x 2 x 1.125 (at 24″Hg) 
