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Industrial ovens are heated enclosures that do not exceed approx. 650 C ( 1200F) in temperature. Most operate in the 250 to 350C range. Higher temperature requirements fall into the furnace category. Ovens are divided into batch and continuous. This section will only cover batch type ovens. Batch type ovens are primarily front loaded and are divided into reach in and walk/truck in.
Reach in ovens range in size from less than 10 cubic feet in volume ( bench top ) to over 100 cu ft, floor mounted on a frame. Most units come with one or two swing out doors. Overhead doors are available on the larger models, but are often a special order. Walk or truck in models range from 100 cu ft to over 700 cu ft. They have side swing doors. Many of these models come with shelf loading capability.
Heat energy is either electric, gas or fuel oil. Steam heat is available for special applications. The power for electric ovens is rated in kilo watts (KW), for gas and oil in BTU per hour. To assure uniform temperature distribution throughout the oven, most models use a fan to recirculate the air. The air flow can be horizontal, front to back or side to side. Or the air flow can be vertical.
The construction, installation and training of the operators of ovens is governed by NFPA 86, the standard from the National Fire Prevention Association. The buyers and potential user of ovens should be familiar with the standard Some manufacturers claim compliance to NFPA 70. This is the national electrical code, which applies to all industrial, commercial and public facilities.
Ovens are classified into Class A, for operation close to atmospheric pressure with flammable or volatile vapors present in the oven. Class B is for ovens operating at or near atmospheric pressure with no volatile or flamable vapors present. Class C operate with special atmospheres in the oven.
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