SmartDry™ Ovens vs. Vacuum Ovens

Product Quality

A typical vacuum oven will anneal the plates, producing very soft plates that can bind and disrupt the plate stacking operation.  Also, the added flexing will increase the pellet loss dramatically in a vacuum oven dried plate.  Tiegel SmartDry™ Dry Charge ovens produce hard plates.

Labor Requirements

Since a vacuum oven requires the plates to be hand stacked approximately 3″ (7 cm) high onto drying shelves, formation cassettes (or racks) cannot be used and the loading/unloading operation is extremely labor intensive.  The worker must handle wet plates, thus being exposed to sulfuric acid.  A vacuum system does not lend itself to element drying.  The Tiegel SmartDry™ Dry Charge machines are designed to dry either elements (using tackless formation components where the panels are loaded into formation cassettes (racks) for formation and drying) or groups.  The plates are only handled during loading and unloading of the cassettes, and the worker only comes in contact with dry plates.

Drying Time

A vacuum oven typically takes 8 – 16 hours to dry plates.  The Tiegel SmartDry™ Dry Charge oven will dry plates in 24 minutes making the washing aspect more efficient and producing better quality plates.

Drying Method

A vacuum oven dries plates by electrically heating the shelves that the plates are stacked on.  The drying is often inconsistent because of uneven heating – plates at the top of the stack remain too cold and the plates at the bottom of the stack are over-heated.  The Tiegel SmartDry™ Dry Charge oven utilizes the principles of convection to produce consistently and evenly dry plates by circulating hot air around the plates.

Cost

A vacuum oven uses electricity to heat the shelves.  The cost of electricity is about 2-1/2 to 3 times the cost of methane gas in the United States. A Tiegel SmartDry™ Dry Charge oven can use any type of readily available combustible fuel – from methane and propane to coal oil.

Maintenance

A vacuum oven has a much higher maintenance schedule because of the inherent problems with trying to maintain a vacuum while exposing the gaskets and seals to the heat generated in the drying process.  In addition, there are many service aspects of a vacuum pump that need to be attended to on a regular basis, causing system shut-downs.  The Tiegel SmartDry™ Dry Charge oven runs on positive pressure – seals only need to be replaced on an annual to biannual basis during regular plant maintenance shut-downs.