Vacuum and protective gas both reduce the activity of oxygen-dependent microorganisms inside the packaging. This way, vacuum-packaged foodstuffs have a longer shelf life, even without preservatives. There are different types of vacuum packaging. When it comes to cheese, the type of vacuum packaging depends heavily on the specific type of cheese.
Building a vacuum system solution is always a joint undertaking. Each solution aims to be compliant with location regulations, as well as to be reliable, energy-saving, sustainable and economical. An essential part of the process is including the customer and their requests during the planning process. There are six steps to find the optimum vacuum solution for the respective application.
Electronics applications typically run their tooling requiring Process Vacuum based on differential pressure from barometric; that is, they control their PVAC pumps to “Inches of Mercury Vacuum”. This is because the parts and pieces being manipulated by vacuum are of certain sizes, shapes, and weights. If the differential pressure across the part is not great enough, then the tooling will fail and result in a loss of product, adverse impact to quality, and production downtime.
SupremeX, a Canadian based envelope and packaging manufacturer, with 11 facilities across six provinces, as well as five facilities in the United States, recently upgraded the vacuum system in their Winnipeg based plant. This article discusses the system before and after the changes, and the significant energy savings, plus improved system reliability that resulted. The company also captured a significant utility incentive to help with the cost of a new cutting-edge variable speed vacuum pump.
Vacuuming fresh food using chamber machines is often a daily activity in butcher shops, at fresh food counters for meat, sausage, and cheese products, as well as in the foodservice industry. All fresh foods contain more or less unbound water, which partially evaporates during vacuum packaging. This can influence the quality of the product. Furthermore, if the packaging machine is not permanently in operation, the packaging result may deteriorate, or the packaging process may take too long.
Operating the vacuum system at higher levels (then necessary) affects the needed volumetric flow to compensate for leaks. This required compensation of volume (ACFM) must be added to the nominal production flow demand. The ambient air leak into the system will expand to the highest vacuum level, which is known as the “Expansion Ratio.”
What is vacuum as used in the manufacturing/industrial sector? The clearest answer is – a contained space with gaseous pressures much less than surrounding atmospheric pressure. Atmospheric pressure (ATM) is expressed in many units of measure. At room temperature a cubic foot of contained air at sea level – the random movement and molecular impact on the walls of the containment vessel equal a force of 14.7 psia for every square inch of the walls.
An envelope manufacturer is upgrading their vacuum system to include a new VSD controlled pump. As part of the preparation for the installation, an energy baseline was developed, and leakage survey conducted. The auditor used a newly developed acoustic imaging camera as well as a basic ultrasonic leak detector gun. This article describes what was found and some of the challenges faced in detecting leaks in a busy plant.
A paper machine carefully removes water from the paper sheet. Some of this water removal is done by passing air through the sheet, thus moving the water from the sheet to the wire. Air is moved by creating a pressure differential across the sheet. This is normally done by putting the sheet on a wire and then putting a box under the wire and then evacuating the air from the box. The resistance of the air movement through the sheet and wire causes the pressure drop from the machine room to the box.
Many of us are familiar with sizing vacuum pumps based on throughput, process pressure requirements, chamber size, pump down times, conductance and leakage. In a lot of cases, humidity becomes an afterthought and unexpected things happen. Some of these unexpected things we learn to live with, like emulsified oil. In other cases, the unexpected things prevent the pump from performing the job it was intended for.
Vacuum can be used in many ways for the meat processing and packaging industry. From mixing ingredients to evisceration (removing organs, excess fat, bones, etc.), to the washing/preparation of the meats or even in the packaging of the meat itself, vacuum is critical to the industry.