A paper manufacturer was having issues with their measuring equipment (reference photo above). They were producing 6” (152mm) wide crepe paper which is very thin and dusty. As it would pass through the machine, a real-time measurement of basis weight and moisture content was being performed. The basis weight of the sheet was around 14g/m2 which is like facial tissue. The machine was giving false errors in the basis weight measurement. As they opened the device, they noticed dust particles on the optical lens. Because the basis weight was so small, any dust would cause a false reading. They contacted EXAIR to see if we could help with their problem.
With a dry fibrous material like crepe paper, static can be a big issue. Static has a strong force that can cause small fragments to “stick” to surfaces. As you can see in the photo, the paper material is sticking to the sides and lens of the measuring device. For this application, I recommended two pieces of the model 112206 Gen4 Super Ion Air Knife Kits. The Gen4 Super Ion Air Knife is uniquely designed to have two functions; remove static and blow off dust. The Gen4 Ionizing Bar creates both positive and negative ions to remove any type of static charge. The Super Air Knife creates a laminar air stream to carry the ions and also generate an even blowing force to remove the dust particles from the surface. With this combination, it becomes a very effective non-contact way to remove the contamination. This was an important requirement as the crepe paper is very thin and could break very easily. They were able to mount one Super Ion Air Knife above and below the paper in order to blow the dust particles in a counter-flow direction. This would keep the particles from entering the measurement device.
The Super Ion Air Knife Kit includes the Super Air Knife with a Gen4 Ionizing Bar attached. The kit also includes a power supply, filter, regulator, and a shim set. The power supply is specifically designed for the Gen4 Static Eliminators. The Gen4 Super Ion Air Knives use the high voltage from the power supply to generate enough ions to remove static from the paper at a running speed of 49.5 ft/sec (15m/sec). The filter will remove any contamination and liquid water from the compressed air system before it enters the Super Ion Air Knife. This is important to keep the product clean. The shim set is a set of three different shims with a thickness of 0.001” (0.025mm), 0.003” (0.076mm), and 0.004” (0.1mm). They are used to dramatically change the blowing force from the stock shim at 0.002” (0.05mm) thick. Being that the paper was extremely thin, they opted to put the 0.001 (0.025m) thick shim inside the Super Ion Air Knife. With the regulator in the kit, the customer could “dial” in the correct amount of force to keep the machine running optimally without breaking the delicate paper.
When the customer installed the Gen4 Super Ion Air Knives just before the entrance into the measuring device, the air stream was able to carry the ions to neutralize the static and to remove the dust from the paper surface. The system was now able to make accurate measurements without disruptions.
For this customer above, the Gen4 Super Ion Air Knives made their system run accurately and consistently by removing any pesky dust particles. If you have an optical device that needs to stay clean, you can contact an Application Engineer to review your application.
John Ball
Application Engineer
Email: johnball@exair.com
Twitter: @EXAIR_jb