Circuit Board Tunnel Oven

To achieve uniform heat distribution in the Circuit Board Tunnel Oven, merely relying on heating is not sufficient; precise fluid dynamics control is also necessary. As a large manufacturer, Dingfeng has designed a pressurized exhaust system that can form a vertical and turbulent-free air curtain over a 700-millimeter conveyor belt width. Driven by a 2.2-kilowatt long-axis motor and a 12-inch SUS304 impeller, it can press the purified hot air into the tiny pores of multi-layer circuit boards. This is particularly important for flexible printed circuits, as it can stabilize the lightweight substrate, allowing it to come into contact with the Teflon mesh belt, avoiding the oscillation and movement phenomena commonly seen in standard convection ovens.

Working principle

The DFHK7008 model Circuit Board Tunnel Oven uses stainless steel heating tubes for heating. It is combined with a low-noise hot air circulation fan and the under-box return air ventilation technology. The hot air, after being processed by the high-temperature efficient filter, is evenly pressed onto the surface of the product. It can achieve automatic temperature control, constant temperature, and automatic stop at over-temperature, featuring safety, convenience, environmental protection, and energy conservation. The interior of the oven is entirely made of mirror-finish stainless steel plates. The insulation layer is filled with 120K silicic acid aluminum insulation cotton. The conveying uses high-quality Teflon high-temperature resistant mesh belt, and is equipped with a controller and frequency converter controlled by the low-voltage electrical control system.

Quality of configuration

The electrical control system of the Circuit Board Tunnel Oven is equipped with components from top brands both at home and abroad, including Mitsubishi H5U-1614MTD-A8 PLC, MT8102iE touch screen, DTE-10T temperature control module, and K-type WRNT-01/02 probes for precise temperature measurement of the heating execution part. The three-phase controllable silicon module J3-SCR-75LA is driven for stable power regulation. In terms of the transmission system, two Shilin frequency converters (220V 0.4KW and 380V 3.7KW) with communication functions and Schneider series components are equipped, including 3P+N-C 250A leakage circuit breaker for total power protection. The LC1N series AC contactors (1810, 1210, 4011) of multiple specifications are responsible for the opening and closing of each circuit, and are combined with LRN12N thermal relay and MY4NJ intermediate relay to ensure the extremely high stability and safety of the equipment operation from the source to the terminal.

Main component model

FAQ

Q1: How does this oven prevent the "Popcorn Effect" in multilayer PCB baking?

A: The "Popcorn Effect" occurs when trapped moisture expands too rapidly. Our Circuit Board Tunnel Oven  utilizes SCR-controlled linear heating ramps. By precisely controlling the rate of temperature rise, we allow internal moisture to diffuse safely through the pre-preg layers before reaching peak sintering temperatures, ensuring the interlaminar bonds remain intact.

Q2: Is the airflow powerful enough to dry high-aspect-ratio through-holes?

A: Yes. Our Down-draft Pressurized Plenum is specifically designed to drive hot air into high-aspect-ratio vias. The vertical pressure ensures that the air penetrates the holes rather than just skimming the surface, which is essential for complete dehydration before the soldering or plating phases.

Q3: Can we integrate this tunnel oven into a fully automated SMT line?

A: Absolutely. The Mitsubishi PLC and Frequency Conversion Motors are designed with reserved linkage points for Industry 4.0 connectivity. The conveyor speed and temperature data can be synchronized with your upstream pick-and-place robots or downstream inspection stations, ensuring a seamless, automated workflow.