Industrial Utility Efficiency    

Rotary Screw Vacuum Pumps Benefit Meat Packaging Plants

Meat packaging plants have long used vacuum pumps as a way to remove air and reduce the amount of oxygen in their products’ plastic packaging. Vacuum packaging extends the meat’s shelf life while protecting its flavor and exposure to outside elements, such as freezer burn and bacteria.

Traditionally, meat packaging plants have used rotary vane vacuum pumps in their facilities without giving much thought to the technology’s energy consumption and maintenance costs. The rotary vane pumps are turned on at the start of the shift and left running at full capacity until end of day.

 

Atlas Copco GHS VSD+

Atlas Copco’s GHS VSD+ rotary screw vacuum pumps.

 

Rotary vane pumps are a positive displacement pump. The pump’s rotor contains sliding vanes that use centrifugal force to slide the vanes in and out of the rotating rotor while sealing and maintaining contact with the pump housing. As the vanes rotate, they expand the opening and create chambers where fluid enters. The chambers get smaller as the vanes continue to rotate and retract, which forces the fluid to exit through the discharge port. The resulting contact between the rotating vanes and the pump’s rotor and housing create wear in the pump.

In 2016, two prominent meat packaging facilities decided to run trials that compared their rotary vane vacuum pumps to Atlas Copco’s GHS VSD+ rotary screw vacuum pumps, as recommended by Pierre Matschke, a business line manager of the Oil-Free Air Division at Atlas Copco. The results were a pleasant surprise. They found a 17 percent increase in energy savings, fewer equipment overhauls and better uptime. And the bottom line? Overall lifecycle costs were much lower when using rotary screw technology.

 

Atlas Copco installation

The header is recognizable, located above the vacuum pumps, more commonly seen in compressed air configurations.

 

Rotary screw vacuum pumps contain two intermeshing screws that rotate in opposite directions within a stationary housing to pressurize and move fluid along the screws’ axis. Often times, the pump is equipped with oil-lubricated gears located outside the pumping chamber, which keep the screws rotating properly. With the rotary screw vacuum pump design, the screws never come in contact with the housing, resulting in less equipment wear and fewer overhauls.

Since 2016, more meat packaging facilities across the U.S. and around the world have switched to rotary screw vacuum technology for reliability, energy efficiency, increased uptime and lower maintenance costs. Instead of overhauling their rotary vane pumps, packaging plants in Kansas, California, New Jersey, North Carolina, Illinois and across Europe have chosen to replace them with Atlas Copco rotary screw vacuum technology to decrease life cycle costs.

 

Reliability

Rotary screw vacuum pumps are designed and assembled to have no metal-to-metal contact within the pump housing, which means there’s minimal wear on the pumps and the equipment’s capacity remains unchanged over the years.

The pump’s canopy includes hot and cool zones. These zones are responsible for isolating the heat produced from high temperature components to avoid condensation, while assuring perfect cooling and long life to the electronic components.

The design, open structure and slow rotation speed of rotary screw pumps make it a heavy-duty option that operates reliably for many years without trouble. Packaging plants no longer have to worry about pumps breaking down during production hours and causing a system shutdown that results in costly labor hours.

 

Energy Efficiency

It’s fairly common to find 25 hp rotary vane vacuum pumps in meat processing plants. In switching to a 15 hp GHS 730 VSD+ Atlas Copco vacuum pump, customers receive more flow rate and reduce install power by 40 percent. While users of rotary vane pumps normally see a low vacuum of 2 to 3 mbar, rotary screw pumps can achieve vacuum at 1 mbar or less. The deeper vacuum helps remove more air and oxygen from the meat’s packaging to deliver a better product for customers.

Operating power is also slowed with use of the Atlas Copco’s Variable Speed Drive (VSD) technology. The VSD pump automatically adjusts its motor and element speed to the lowest level possible. Therefore, flow is delivered to match the application’s required vacuum level, saving an average of 50 percent in energy consumption. The VSD vacuum pump eliminates the need for frequent starts and stops when there’s variable demand. In turn, users experience fewer motor problems, such as overheating, fan breakage, oil degradation and vane delamination.

Optional energy recovery components can be integrated into the rotary screw system, allowing users to recover heat generated by compression. Without sacrificing pump performance, recoverable energy levels of up to 75 percent are even possible in some applications. Meat packaging plants also benefit from the unit’s ability to keep the heat release within vicinity of the units so it does not affect nearby workstations.

 

 Atlas Copco Vacuum pump

In switching to a 15 hp GHS 730 VSD+ Atlas Copco vacuum pump, customers receive more flow rate and reduce install power by 40 percent.

Lower Maintenance Costs

Rotary screw pumps need less maintenance. While rotary vane pumps are overhauled on an average of every 3 to 4 years, or every 16,000 running hours, rotary screw pumps can run 48,000 hours until it needs an overhaul, which averages every 11 to 12 years. Over a 10-year period, this can result in a reduction of close to 89 percent in overhaul costs. And when maintenance is required, it’s easy for your trained maintenance staff to fix the issue. Given the savings on power and maintenance costs alone, users see a return on investment in less than two years.

 

Increased Uptime

Rotary screw vacuum pumps like the GHS VSD+ feature plug-and-play installation. Install time is minimized so meat processing plants can quickly resume operations when replacing their vacuum systems. The GHS VSD+ also comes with a SMARTLINK connectivity option for maximum uptime. The SMARTLINK remote monitoring system keeps users informed of pump performance and maintenance requirements throughout the day.

The inherent design of rotary vane vacuum pumps makes them prone to expensive overhauls that require time and money. Recent trials show that using the GHS VSD+ increases production rates by close to 20 percent because less time is spent on maintenance issues and the additional flow at deeper vacuum levels allow increased speed on the packaging equipment.

Screw vacuum pump technology is beginning to transform the way meat processing plants are thinking about the vacuum pumps they use in their facilities. Independent tests and trials repeatedly point to the advantages of using rotary screw vacuum pumps in place of vane pumps. Plants are getting higher flow with minimum absorbed power for lower energy consumption and the screw pump’s VSD technology can adjust flow based on application demands. With longer periods between overhauls, facilities are decreasing their maintenance costs and increasing uptime for better reliability and operating efficiency.

To see if rotary screw vacuum technology is right for your processing facility, contact a vacuum solutions expert.  

 

For more information, please contact Jerry Geenen, Vice President and Business Line Manager, North America Utility Vacuum, Atlas Copco Compressors, tel: 803-817-5736 or visit www.atlascopco.us.

To read similar articles on Industrial Vacuum Systems, please visit www.blowervacuumbestpractices.com/system-assessments/vacuum-systems.