| To a precision metal tubing manufacturer
producing a product that meets precise tolerances is not good enough. Keeping customers
satisfied also means the tubing must be free of any residue from various chemical
solutions used during fabrication. Having a wide variety of
customers, their products can be found in many applications. From automobile rocker arms
and cam shafts, to lawn and garden equipment, and as magazine tubes on rifles and
shotguns. For each application, a close tolerance, clean, residue-free tube is delivered.
Keeping the tubes free of chemical residue is challenging.
After arriving at the plant, the stock is degreased and placed in a dip
tank containing sulfuric acid. It is then coated with zinc phosphate, drawn,
machined and degreased a second time in a sodium hydroxide solution. Finally it is
neutralized in an alkali bath and protected with a synthetic oil coating to prevent rust.
The combination of oil, water and chemical residue presented a unique
challenge. It is critical that the chemical residue does not move downstream from one dip
tank to another. During the process, chemical residue floats on the surface of the tanks,
oil is in the middle and water on the bottom.
To remove the residue, employees would hand skim the tanks when the plant was shutdown
on weekends. Hand skimming was messy, time-consuming, costly and inefficient. It never
allowed for an effective separation of the oil and the chemicals. It was not possible to
recycle "clean" oil back into the process.
Looking for an alternative, the decision was made to install the Tote-It®
Portable Oil Skimmer from Abanaki Corporation on a trial basis. The Tote-It
utilizes a continuous belt and wiper to remove up to 12 gallons of oil per hour from a
liquid's surface. |
The 4" wide belt operates on a motor and
pulley system. The system is attached to a stabilizer bar that is immersed in the liquid.
After traveling over the head pulley, the belt passes through tandem wiper blades where
oil is scraped off both sides of the belt. The oil is discharged through a 1-1/4" ID
hose. The skimmer's effectiveness rests in the differences in
specific gravity and surface tension between oil and water.
These characteristics allow the belt to attract oil and other
hydrocarbon liquids from the fluid surface.
Because of the Tote-It Portable Skimmer's success, the decision was made to buy two of
Abanaki's Oil Grabber® Model 8 Skimmers with 8" wide
belts. These units operate on the same principle as the Tote-It Portable Skimmer, but have
the capacity to remove up to 40 gallons of oil per hour.
The switch from manual to mechanical skimming resulted in immediate
benefits. Dip tanks were cleaner with much less residue carry-over from tank to tank. This
eliminated the need for weekend overtime for hand skimming. Material costs and downtime
also reduced, since the oil is recycled longer and tanks need to be drained and refilled
much less often. Finished product quality has improved, resulting in greater customer
satisfaction.
Today the tube manufacturer has earned ISO 9000 certification. The
mechanical oil skimmers have played a key role. The skimmers have become an important part
of the plant's quality control process. |
