It is important to use the right vacuum pump for vacuum table processes, as the required vacuum force varies widely depending upon the size of the part and the application required. A vacuum pump is used with a vacuum table to hold down parts and various substrates during processes applications such as:
- CNC machining
- Cutting
- Plotting
- Engraving
- Ultrasonic cutting
- Scanning
- Screen Printing
- Material handling systems
- Dozens of other industrial or commercial processes
Understanding Vacuum Force
Some people might think that the more horsepower the better, assuming that increased vacuum force will result in better hold-down force no matter the part or process. Increased HP will definitely yield increased electric bills, but do you really need the maximum force available?
Vacuum pumps for vacuum tables do much more than just hold the part down by sucking it down with air. There are many factors to consider when choosing the right vacuum pump, and a thorough understanding of how these forces work helps us to choose the right vacuum pump and table for the job.
The weight of air, or the atmospheric pressure, is approximately 15 pounds per square inch (psi), which means that when at sea level on a day with a standard temperature of 59°F, air weighs in at 15 lbs. per square inch. Picture a one square inch column of air, that ascends indefinitely into the atmosphere. This column of air would have the pressure of 15 pounds. The higher the elevation the less amount of pressure, so this is drastically reduced at the top of a mountain compared to sea level.
Heat also plays a factor in the amount of vacuum force required, as hotter temperatures mean air molecules are farther apart, and the same amount of vacuum force will not hold with as much force in high temperature environments. Thus, the elevation and temperature greatly affect vacuum force.
It is important to remember, however, that a column of air is fluid and will attempt to replace all vacuumed areas. Since the maximum amount that air can weigh is 15 lbs. per square inch, it cannot be forced to weigh any more than that with any type of vacuum pump as you are simply vacuuming out what is there.
Factors to Consider When Choosing a Vacuum Pump for Vacuum Tables
Surface area – The surface area of your part is a very important consideration when choosing the right vacuum pump and table. Large flat parts do not require as much vacuum force as small parts. More vacuum is needed to hold smaller parts solidly in place due to the smaller surface area. The contact surface area between the object and the vacuum holes is a key factor to consider.
Friction – The friction between the surface of the vacuum table and your object is another important factor to consider when choosing the right vacuum pump. If your table surface is slippery the objects may tend to slip regardless of the amount of vacuum force applied. With a non-slippery surface and enough downward force applied, objects are more likely to stay in place.
Air Permeability – the air permeability of your object is an important consideration that will affect the amount of vacuum force required. You would not necessarily need the same amount of force when holding down a sheet of aluminum compared to paper or canvas.
Experienced Vacuum Table Specialists at Systematic Automation
Systematic Automation is a leading manufacturer of vacuum tables and pumps, with the knowledge and expertise to assist you in choosing the most advantageous vacuum force for your process. We have been designing, engineering and manufacturing vacuum tables and pumps as well as screen printing machines for more than 35 years. We understand the technology behind the equipment, and have developed patented products with proprietary technology to provide the best vacuum tables in the industry.
Our tables are superior in flatness, boasting +/-.001” per linear foot even in our oversized vacuum tables. No job is too large or small, we provide vacuum tables ranging from 5” x 6” up to 72” x 144”.
Vacuum Pumps for Any Application
Our ½ HP Regenerative Vacuum Pump provides continuous quiet duty, 56 CFM, 120 Volt 60 hz, and is CE approved. The Regenerative pump is ideal in light CNC machining applications, and for holding down flexible or flat materials used in printing, engraving or photography. The hold down force of this pump is not quite as strong as the Rotary Vane pump, although a few exposed holes in your table will not greatly reduce your hold down power.
The Rotary Vane Pump provides very strong hold down power, and is used in CNC machining and other applications that require stronger holding force. This vacuum pump emits a low flow and may require sealing the workpiece as open or exposed holes on the vacuum table greatly reduces the holding power.
Contact the vacuum experts at Systematic Automation for answers to all your questions regarding the proper type of vacuum pump for your application. Our engineers are ready to assist you with the right equipment for your process, without paying more than you need to. We offer dozens of standard sizes or will custom design and manufacture the perfect vacuum table for your process.
Systematic Automation leads the industry with vacuum pumps and tables featuring superior flatness and hold down force. We will custom design a solution for you, ensuring that you have the right equipment for your process. We have more than three decades of experience with design, engineering, manufacturing, and installation of high performance automated equipment used in screen printing, UV curing and vacuum table systems. Contact us today to speak with a knowledgeable engineer and for all your vacuum table solutions.
