New Gruenberg Custom Industrial Truck-In Oven
A manufacturer of power-generation equipment asked Thermal Product Solutions to design a custom industrial oven that would remove moisture from exhaust filters used in diesel truck engines after the filters have undergone an environmentally friendly cleaning process to remove particulate matter. The insulated, stainless-steel and cordierite-ceramic filters are dipped in a liquid-acid cleaning solution to remove the particulates before being placed in the oven for drying at 1200 °F.
The new, custom-industrial Gruenberg Truck-In Oven features a high-volume, 18,000-cfm, compound, horizontal-air-circulation system and offers 144 cubic feet of internal workspace. It accommodates two, three-tiered, stainless-steel hand trucks, each carrying 12 filter assemblies for a total product load of 24 filters and more than 1,400 pounds. Before drying, each filter assembly weighs approximately 60 pounds.
With a full product load, the natural-gas-fired oven ramps from an ambient air temperature of 70 °F to the customer’s chosen operating temperature of 1200 °F in three hours. The filters soak at that temperature for one hour, after which time heating is discontinued. The industrial oven then cools the product load to 125 °F with the help of an exhaust system that operates at 2,000 cfm. The unit has a maximum temperature of 1250 °F and is constructed of a heavy-duty, welded steel frame, the unit features a 309L stainless-steel chamber liner and includes eight inches of Fiberex insulation.
The truck-in oven utilizes a one-million-BTUH, direct-fired, Eclipse Inline horizontal-firing gas burner. The gas-heat system and fuel train are built to National Fire Protection Association, Factory Mutual Insurance, and Industrial Risk Insurers standards. Safety systems include a latching, manual-reset, main gas valve; purge timer; pressure-release panel; powered exhauster; high- and low-gas pressure switches; leak-test valves; solid-state, electronic, flame-safeguard protection for the igniter and main burner flames; a motorized-back-up, main-safety-shut-off valve; an interior-oven-override safety button; an emergency-stop system; and a light tower with audible alarm. An independent Yokogawa 150L high-limit thermostat de-energizes the heating system if the customer’s pre-set heat limit is reached.
The oven is equipped with a Yokogawa UP55A programmable controller with Ethernet communications that offers proportional integral derivative control with an accuracy of ±0.1%. The controller includes 8 process-variable events, 16 time events and offers 30 available program patterns for a total of 300 linkable segments. A single-pen Partlow MRC5000 chart recorder is also included.