Continuous Baking LineThe industrial continuous baking line is an industrial equipment system designed based on "uninterrupted conveying + precise temperature control + automated linkage". It is widely used in multiple fields such as chemical industry, building materials, electronics, and food industry. Its core function is to realize continuous baking, curing or ripening of materials, and it is one of the key equipments supporting the large-scale and standardized production of enterprises. Its overall design revolves around the three core goals of "high efficiency, stability and flexibility", and the characteristics of industrial automated production are reflected from its structural composition to working process. The detailed description from multiple dimensions is as follows:

I. Core Positioning and Core Value of the Equipment

1. Core Positioning

As the "intermediate processing link" in the industrial production line, the industrial continuous baking line undertakes the pre-processing (such as coating, forming) of materials and the post-processing (such as sorting, packaging). It assumes the key task of "changing the physical/chemical properties of materials through the action of temperature". For example, in the chemical industry, it cures the coating on the surface of metal parts; in the building materials industry, it enables fire-proof boards to achieve a stable structure; in the electronics industry, it ensures the drying and shaping of welding points on circuit boards; and in the food industry, it realizes the ripening of raw materials and the enhancement of flavor.

2. Core Value

Compared with traditional intermittent baking equipment (such as batch ovens), its core advantages are reflected in three aspects:

• Efficiency Improvement: It supports 24-hour continuous operation. The conveyor belt conveys materials at a constant speed without batch interval waiting time. The production capacity is 30%-50% higher than that of intermittent equipment. (Taking the chemical coating line as an example, the daily processing area can reach more than 5,000 square meters, which is far higher than the single processing capacity of batch ovens.)

• Stable Quality: Through technologies such as segmented temperature control and hot air circulation, it ensures uniform temperature in all areas of the tunnel (temperature difference ≤ 5℃), avoids product quality fluctuations caused by differences in manual operations or local temperature differences, and stabilizes the product qualification rate above 98%.

• Cost Optimization: The fully automated process only requires 1-2 staff to monitor the operation of the equipment (no need for manual frequent feeding, discharging and parameter adjustment), which greatly reduces labor costs. At the same time, the machine body is designed with high-temperature resistant thermal insulation cotton, which reduces heat loss by 20%. Some models also support waste heat recovery for the preheating link, further reducing energy consumption costs.

II. Composition and Functions of the Core Systems of the Equipment

The structure of the industrial continuous baking line can be decomposed into five core systems. Each system works together to realize continuous baking. The specific composition and functions are as follows:

1. Conveying System: The "Carrier" for Continuous Material Movement

The conveying system is the "framework" of the equipment. It is responsible for conveying materials from the feeding end to the discharging end, running at a constant speed throughout the process with adjustable speed. Its core components include:

• : High-temperature resistant materials are selected according to the characteristics of materials, such as metal mesh belts (suitable for chemical coating parts and electronic components, with strong load-bearing capacity and air permeability), ceramic pallets (suitable for thick materials in the building materials industry, with high-temperature resistance up to 500℃ or above), and food-grade stainless steel belts (suitable for food raw materials, meeting hygiene standards).

• Speed-Regulating Motor: The conveying speed is adjusted through the PLC control system (the range is usually 0.5-5 m/min). The speed needs to be accurately matched with the baking time and production capacity requirements. For example, if a building materials line takes 30 minutes to complete the baking of boards, and the length of the tunnel is 10 meters, the conveying speed should be set to 0.33 m/min to ensure that the residence time of materials in the tunnel exactly meets the process requirements.

• Auxiliary Structures: Including conveyor belt tensioning devices (to avoid slipping and deviation during operation), guide plates (to ensure materials enter the baking tunnel neatly), and carrier recycling tracks (for example, metal pallets are cleaned and returned to the feeding end for recycling after use, reducing consumable costs).

2. Temperature Control System: The "Core Guarantee" for Baking Quality

The temperature control system is the "brain" of the equipment. It is responsible for accurately controlling the temperature in the baking tunnel to meet the process requirements of different materials. The core components and functions are as follows:

• Segmented Heating Module: The baking tunnel is divided into 3-5 independent temperature control zones. Each zone is equipped with electric heating tubes or gas heating devices (electric heating is mostly used in the chemical and electronics industries, and gas heating is often used in the building materials industry due to the need for high temperature). The temperature can be set separately (the range covers 60-500℃), which is suitable for the stepped process of "preheating - baking - heat preservation" (for example, food baking requires preheating at 60-120℃ first, then core baking at 150-250℃).

• Temperature Sensor: 2-3 high-precision sensors (accuracy ±1℃) are installed in each temperature control zone to collect the temperature data in the tunnel in real time and feed it back to the control system. If the temperature deviates from the set value, the system will automatically adjust the power of the heating module (such as increasing the heating power when the temperature is too low and pausing the heating when the temperature is too high).

• Over-Temperature Protection Device: When the temperature exceeds the safe range (such as over 300℃ for chemical lines and over 200℃ for electronic lines), the device will trigger automatic shutdown and give an alarm to avoid material damage or equipment failure.

3. Hot Air Circulation System: The "Key Support" for Uniform Temperature

The hot air circulation system ensures that there is no dead angle of temperature in the tunnel and avoids uneven ripening or curing of materials due to local temperature differences. Its core design includes:

• Multiple Sets of Fans and Air Ducts: Centrifugal fans are installed on the top, bottom or side of the baking tunnel. Combined with the spiral air duct design, the hot air flows circularly in the tunnel (air speed is about 2-3 m/s). Especially for thick materials (such as building materials boards), the upper and lower double-fan design is required to ensure uniform temperature on the upper and lower surfaces of the materials.

• Air Volume Adjustment Function: Some high-end equipment supports hierarchical adjustment of air volume. For example, reduce the air volume in the preheating stage (to avoid rapid evaporation of water on the material surface) and increase the air volume in the core baking stage (to accelerate the internal curing of materials).

4. Cooling System: The "Transition Link" for Post-Processing of Materials

After baking, the temperature of materials is extremely high (close to the baking temperature). The cooling system needs to quickly cool them down to the temperature required for post-processing or packaging (usually below 50℃) to avoid material deformation, deterioration or scalding of staff. There are two common forms:

• Forced Air Cooling: A cooling section is connected to the discharging end of the baking tunnel. Multiple sets of cooling fans (some equipped with refrigeration devices) are installed to cool the materials by blowing cold air directly on them. The cooling time can be controlled within 5-20 minutes (for example, biscuits need to be cooled to below 40℃ within 10 minutes after baking to avoid moisture regain after packaging).

• Water Cooling Assistance: For high-temperature materials (such as boards baked at 500℃ in the building materials line), cooling water pipes (with heat sinks wrapped around the outside of the pipes) are installed in the cooling section to further accelerate the cooling through heat exchange, and at the same time avoid material cracking caused by direct cold air blowing (for example, ceramic green bodies need slow cooling and require a combination of water cooling and natural cooling).

5. Control System: The "Operation Center" for Automated Equipment Operation

The control system adopts PLC (Programmable Logic Controller) + touch screen design to realize the integrated operation of equipment parameter setting, operation monitoring and fault alarm. The specific functions include:

• Parameter Presetting and Storage: Staff can preset parameters such as temperature, time and conveying speed according to different material processes (such as 250℃ baking for 30 minutes for chemical coating parts and 180℃ baking for 15 minutes for electronic components), and store them as different programs (10-20 groups of programs can be stored). When switching materials, the programs can be directly called without repeated settings.

• Real-Time Monitoring Interface: The touch screen displays real-time data such as the temperature of each temperature control zone, the speed of the conveyor belt and the operation status of the fan, and marks the equipment status with different colors (green for normal and red for fault).

• Fault Alarm and Diagnosis: When an abnormality occurs in the equipment (such as conveyor belt jamming, temperature sensor failure, fan stop), the system will immediately issue an audible and visual alarm and display the fault location and cause on the touch screen (such as "Abnormality of Sensor in Temperature Control Zone 2"), facilitating staff to quickly troubleshoot and repair.

III. Typical Working Process (Taking Chemical Coating Parts Baking as an Example)

The working process of the industrial continuous baking line revolves around "feeding - preheating - baking - cooling - discharging - carrier recycling". Each link is linked through the conveyor belt to form an uninterrupted production cycle. Taking the widely used chemical coating parts (such as anti-corrosion coating on the surface of metal anti-theft doors) baking as an example, the process is described in detail as follows:

1. Feeding Preparation Link (1-2 minutes per piece)

• Staff neatly place the coated metal parts (such as anti-theft door panels) on the metal pallets (1-2 pieces per pallet, ensuring that the coating surface is not blocked or overlapped).

• The pallets are conveyed to the entrance of the baking tunnel through the feeding conveyor belt. The guide plates correct the position of the pallets to avoid deviation after entering the tunnel.

• The control system adjusts the conveying speed (set to 1 m/min) according to the preset production capacity (such as processing 30 pieces per hour) to ensure that the pallets enter the tunnel at fixed intervals.

2. Preheating and Shaping Link (10 minutes)

• The pallets enter the first temperature control zone (preheating zone) of the baking tunnel, and the temperature is set to 120℃.

• In this stage, low-temperature slow heating is used to remove the residual water on the coating surface (to avoid bubble formation due to water evaporation during subsequent high-temperature baking, which leads to coating peeling).

• The hot air circulation system operates at low air volume to ensure that the temperature on the coating surface rises uniformly without local sudden heating.

3. Core Baking Link (30 minutes)

• The pallets enter the second and third temperature control zones (core baking zones) in sequence, and the temperature is set to 250℃.

• The heating module continuously heats, and the hot air circulation system increases the air volume (air speed 2.5 m/s) to make the hot air evenly wrap the metal parts, ensuring that the coating is completely cured from the surface to the inside (the coating curing degree needs to reach more than 95% to meet the anti-corrosion requirements).

• The temperature sensor collects temperature data every 10 seconds. If the temperature in a certain area is lower than 248℃, the control system automatically increases the heating power of that area to ensure that the temperature is stably maintained at 250±1℃.

4. Cooling Link (20 minutes)

• The pallets enter the fourth temperature control zone (cooling zone), and the cooling fan starts to blow cold air directly on the surface of the metal parts.

• The temperature is gradually reduced from 250℃ to 45℃ (to avoid metal part deformation or coating cracking caused by excessive temperature difference). During the cooling process, the temperature sensor monitors in real time to ensure that the cooling rate is controlled within 10℃ per minute.

• Some equipment is equipped with dust covers in this link to prevent dust in the air from adhering to the coating surface during cooling, which affects the appearance quality.

5. Discharging, Sorting and Carrier Recycling Link (1-2 minutes per piece)

• The cooled pallets are conveyed to the discharging end by the conveyor belt. The automatic turning plate mechanism turns over the pallets, and the metal parts fall into the sorting table below.

• Staff (or visual inspection system) check whether the coating has defects such as bubbles and scratches, and remove unqualified products (the qualification rate is usually ≥98%).

• The empty pallets are conveyed to the cleaning device through the cleaning conveyor belt (high-pressure air gun blows off the residual dust on the surface), and then returned to the feeding end to enter the next cycle.

IV. Application Fields and Industry-Specific Customization Requirements

The industrial continuous baking line has strong versatility, but due to differences in material characteristics and process requirements in different industries, customized design is required. The main application fields and customization points are as follows:

1. Chemical Industry

• Application Scenarios: Curing of anti-corrosion coatings on metal parts, curing of spray coatings on plastic parts, baking for resin forming, etc.

• Customization Points: Explosion-proof design is required (some coatings will produce flammable and explosive gases during baking). Explosion-proof fans, explosion-proof motors and combustible gas detection devices should be equipped. The temperature control range is 200-300℃, and the temperature control accuracy is required to be ±1℃ to avoid insufficient or excessive coating curing.

2. Building Materials Industry

• Application Scenarios: Curing of fire-proof boards, drying of thermal insulation boards, preheating of ceramic green bodies, etc.

• Customization Points: High-temperature resistant design is required (baking temperature 300-500℃). The conveyor belt should be ceramic pallets or high-temperature resistant metal mesh belts. The length of the tunnel should be suitable for thick materials (for example, 20cm thick fire-proof boards require more than 30 minutes of baking time, and the tunnel length should be ≥10 meters).

3. Electronics Industry

• Application Scenarios: Drying of circuit boards after welding, curing of glue on electronic components, baking for sensor packaging, etc.

• Customization Points: Clean design is required (to avoid dust affecting the performance of electronic components). The inner wall of the baking tunnel is made of stainless steel, and high-efficiency air filters are equipped. The temperature control accuracy is required to be higher (±0.5℃) to avoid high-temperature damage to components (for example, the tolerance temperature of chips is usually ≤200℃).

4. Food Industry

• Application Scenarios: Drying of puffed food, preprocessing of baking raw materials (such as nut baking), cooling of sauces after boiling, etc.

• Customization Points: Food-grade materials are required (the conveyor belt is 304 stainless steel or food-grade silica gel, and the inner wall is coated with food-grade coating), meeting food safety standards (such as GB 16798). Some products (such as bread and biscuits) require humidity adjustment function, and steam is introduced in the early stage of baking to improve the product taste.

V. Daily Maintenance and Management Points

To ensure the long-term stable operation of the equipment, a standardized maintenance and management system should be established. The core points are as follows:

1. Daily Inspection (15-20 minutes)

• Conveying System: Check the tension of the conveyor belt (press the conveyor belt by hand, and the sinking amount ≤1cm is normal), and check for deviation and wear marks.

• Temperature Control System: Calibrate the temperature sensor with a portable thermometer (the error should be ≤1℃), and check whether the heating module heats normally.

• Cooling System: Clean the filter screen of the cooling fan (to avoid dust blocking affecting heat dissipation), and test the operating noise of the fan (noise ≤75 decibels is normal).

2. Weekly Maintenance (1-2 hours)

• Cleaning and Maintenance: Clean the hot air duct with a high-pressure air gun (to avoid dust accumulation leading to reduced air volume), and wipe the touch screen and equipment surface.

• Lubrication and Maintenance: Add high-temperature resistant lubricating oil (such as lithium-based grease) to the motor bearings and tensioning devices of the conveying system.

• Safety Inspection: Test whether the emergency stop button and over-temperature protection device are normal (the equipment should stop immediately when the emergency stop button is pressed, and an alarm should be triggered and the machine should stop when the temperature is too high).

3. Monthly Maintenance (4-6 hours)

• In-Depth Inspection: Dismantle the temperature sensor for calibration, check whether the heating module has aging phenomena (such as blackening and deformation on the surface of the electric heating tube), and replace it if necessary.

• Conveyor Belt Maintenance: Adjust the deviation of the conveyor belt (adjust through the tensioning device or guide wheel). If the conveyor belt is seriously worn (such as broken wires in the metal mesh belt), it should be replaced in time.

• Control System Maintenance: Back up the PLC program (to avoid program loss), and check whether the line connections are loose (especially the connecting wires between the heating module and the control system).

VI. Future Development Trends

With the development of industrial automation and intelligent technology, the industrial continuous baking line is moving towards the direction of "more intelligent, more energy-saving and more environmentally friendly":

• Intelligent Upgrade: Combined with the Internet of Things technology, it realizes remote monitoring (staff can view equipment operation data through a mobile APP) and data analysis (the system automatically counts production capacity, energy consumption and qualification rate, and generates production reports). Some equipment has supported AI adaptive adjustment (automatically optimizing temperature and speed parameters according