Trial Number 6

Thirteen preweighed coupons were coated with a parrafin wax, by heating the wax with a Master Appliance heat gun and rubbing the coupons with the hot wax. Once cooled, coupons were reweighed. Five coupons were clipped to wire racks and immersed into the Flow-Matic machine and cleaned for 1 minutes using ultrasonics at 92 F, removed and rinsed in a tap water spray and re-immersed into the ultrasonics for an additional 1 minute followed by a second 5 second rinse. The coupons were then dried using an air knife for 15 seconds. A second set of five coupons followed the same cleaning cycle except they were hung on a wire stand and immersed into a Crest 40 kHz ultrasonic tank. The final three coupons were cleaned in water using stir-bar agitation, rinsed with the spray and dried with air knives.

Comparison of the two processes revealed that both system were ineffective at removing the wax from the stainless steel coupons.
Table 1. Cleaning Efficiencies

Water in the immersion cleaning removed about the same amount of wax as the ultrasonic systems.
Wax
-0.32
-0.42
-0.14
-0.30
0.14

Neither system was effective in cleaning the wax.