When the parts are done dripping in an open top degreaser, the parts are raised into the dwell area and drying begins. The drying time is very long compared to vacuum drying as in our airless systems. Operators judge when the parts are dry in the dwell area. Our Airles System simply opens the door and is ready for the next parts.
If immersion is required, the open top degreaser can operate as fast as an airless system since it takes an operator a minute or two to submerge the part in the sump and transfer it to the vapor state. The airless system requires a minute or two to transfer liquid in and out of the chamber. It is difficult to determine the value of an automated system requiring no operator however the automated airless system would waste no time performing the soak step and for sure would be consistent from cycle to cycle.
All of the same processes as practiced in an open-top vapor cleaning system can be well used in an airless system. Examples would be immersion, sonics, superheat, drying, heated immersion, clean immersion etc. In addition, processes maybe combined in an airless system to produce unique processes. For instance, alternating cool spray or vacuum drying cools parts to allow for a second vapor degrease step.
Completely drying the chamber and parts allow for treatment with a second chemical such as passivation or sterilization.
Typically, a vacuum vapor degreaser can more than double your throughput compared to an equivalent open top degreaser. When comparing prices, also include the amount of parts you can get through the unit. The actual cost might surprise you.
As an example, a unit in the field has switched from an OTVD to a VPS Vacuum Cycling Nucleation (VCN) unit. When cleaning a large part, the OTVD takes roughly 1 hour to soak and vapor degrease the part. More often then not, a second cleaning is required to get the part clean enough to braze the part without problems. The VCN unit first vapor degreases for 1 minute, then soaks the part with VCN action for 2 minutes, then cools the part in order to vapor degrease a second time followed by vacuum and heated circulation drying. The cycle is completed in 25 minutes with two parts in the unit. This translates into a 4 to 8 times increase in throughput for a VCN unit. The unit costs less than $300,000. Based on the throughput attained, this translates to a real throughput cost of $38K to $75K.
See COSTS for the additional savings realized by a vacuum vapor degreaser. When considering all the costs, the VCN unit creates significant savings immediately.