Pre-Dry Oven
The oven enclosure is constructed of panels, which are 50mm thick with fiberglass insulation. Removable side guards are provided to access all fan drives and high temperature components. All ducts and fans are insulated to maximize efficiency and reduce energy consumption. For easy access to the yarn sheet the top oven panels will pivot open to allow for the maximum unobstructed access to the yarn sheet. These panels will be equipped with air cylinders and will automatically open at machine stop. An alarm will be provided and will be activated when opening or closing.
Standard Specifications
| Enclosure per oven | 6000mm x 2200mm x 1320 |
| Insulation | 50mm fiberglass |
| Heat source options | steam / steam/electric / gas / hot oil |
| Air flow | Counter flow (opposite yarn direction) |
| Air circulation system | Fans with directional duct with variable speed 3.7kW motors (2-sets) |
| Exhaust system | Exhaust fan driven with variable speed 2.2 kW motor |
| Temperature control | Automatic control with RTD temperature sensors |
Oven Cross-Section
The oven is equipped with two (2) 3.7kw inverter duty AC motors to drive the recirculation fans and one (1) 2.2kw inverter duty AC exhaust fan motor to drive the exhaust fan.
Air is heated in the heating chamber and then moves through the recirculation fans and is introduced into the working chamber at the yarn exit end of the oven. The heat source can be steam, steam/electric, gas or hot oil. The heated air passes through the working chamber against the yarn flow and is drawn into the low pressure chamber at the yarn entrance end of the oven. The inverter driven exhaust fan is ducted to the low pressure chamber where 10% to 20% of the air is removed in the run mode and 50% to 100% is removed in the stop mode. The exhaust air is ducted through the floor, which is connected to ductwork running to the outside of the plant.
Temperature deviation left to right will not exceed 2° C. Temperature deviation front to back in a counter-flow oven is proportional to yarn styling, wet pick-up, speed of the machine and temperature of the dryer.
Temperature control, re-circulating, and exhaust fan speeds will be programmable by style and controlled by the process control system. Oven air temperatures will be measured by RTDs. Air circulation is controlled as a fixed speed or vs. machine line speed (i.e. air circulation increases with line speed).
Exhaust volume is controlled as a fixed speed or by water vapor exhaust volume calculation, where the water entering the oven and is dried has a calculated volume and the exhaust rate is controlled by the controller.
