Automatic ground-chain spraying production line for motorcycle aluminum alloy wheels

We all know that the aluminum alloy wheels of motorcycles are formed by one-piece die-casting, the wheels are flatter, not easy to swing from side to side during driving, not easy to rust, beautiful and diverse styles, and convenient for maintenance. However, due to the complex shape of the aluminum alloy wheels of motorcycles, the large gap between the spokes, and the requirements of spraying on both sides of the spokes and the inside of the wheel, it is difficult to realize the automation of painting. The horizontal spin type motorcycle aluminum alloy full wheel electrostatic automatic coating method has the advantages of high paint utilization rate, low emission of harmful substances, uniform film thickness, stable coating performance, etc., greatly reducing labor intensity, and is completely suitable The spraying of motorcycle wheels is an environmentally friendly spraying production line with great promotion potential.

For motorcycle aluminum alloy wheels, the main purpose of surface coating is to increase the corrosion resistance and surface decoration requirements of the aluminum alloy surface. Among them, high-quality aluminum wheel coating requires a full and uniform paint film and consistent light. Evaluation of the appearance quality of aluminum alloy wheel coating is usually based on the color and gloss consistency of the coating film, dry skin, sagging, particles, and bottoming. It is necessary to improve the surface quality of the coating and reduce defects , Especially for human defects, the most important thing is to increase the degree of automation of the process operation under the premise of stable coating quality.
The equipment composition of the motorcycle aluminum alloy wheel ground-chain electrostatic automatic spraying production line is mainly determined by the process flow, the size of the workpiece, the plant layout, and the production volume. The aluminum alloy wheel of the order carrier is small in size and the output is large, so the equipment It mainly consists of pre-treatment cleaning system, pure water production system, fuel moisture drying and curing heating system, ground chain support and conveying drive system, fixed gun tracking spray electrostatic automatic spraying system,) water treatment system and other related auxiliary equipment. .
1. Pre-treatment and cleaning system for spraying production line
The pre-treatment cleaning system consists of hot water tank, pre-degreasing tank, immersion degreasing tank, spray degreasing tank, surface adjustment tank, passivation tank, immersion washing tank and other washing spray tanks, pure water spray tanks, tanks Liquid heating system, degreasing device and automatic dosing system, these equipment can well meet the requirements of all aluminum alloy motorcycle wheel load degreasing and surface passivation film formation, the key is to ensure that the wheel load The cutting oil and machine oil are removed, and the degreaser residues are rinsed clean in the subsequent water washing, so as to maintain a uniform and fine passivation film on the product surface during passivation, and provide a qualified substrate surface for subsequent coating . In order to achieve the above objectives, the pre-treatment and cleaning process adopts the best technological means of spraying and immersion combined with ultrasonic degreasing; the concentration of the bath liquid is guaranteed at any time to complete the automatic dosing system of the mountain gauge pump to ensure degreasing, surface adjustment, and passivation. The concentration of the bath liquid is controlled within the process range at any time; the bath liquid is heated by a stable and safe oil-fired hot water boiler heating device, which has fast heating speed, high thermal efficiency and significant energy saving effect.

2. Pure water production system for spraying production line
The pure water production system includes pure water production equipment, intermediate storage tanks, pure water storage tanks, pure water delivery pipes, and pure water delivery pumps. The principle of eucalyptus production can generally be divided into reverse osmosis type and electrodialysis type. And ion resin exchange type, the reverse osmosis type is the best, the pure water produced is the best, and the operation is convenient, but the equipment price is higher, and the replacement cost of the reverse osmosis membrane during operation is also higher; ion resin exchange equipment produces pure water Water can also meet the requirements, but the operation is more complicated. (ii) The regeneration requirements of anion and cation resins are quite strict, otherwise the pure water produced will not meet the requirements of pure water for coating, and water marks will easily remain after drying. . According to the actual production situation and investment requirements, the motorcycle aluminum wheel coating line can reasonably select one of the plow-like pure water production systems.
Pure water is used for the last two washing sprays of the pre-treatment to completely remove the residues of chemicals and impurities in the front. At the same time, the residues of the tap water (hard water) spray are also removed. The hard water residues are easily dried after the water is dried. The formation of watermarks affects the performance of the coating film.
3. Fuel moisture drying and curing heating system for spraying production line
The fuel moisture drying and curing heating system adopts a bridge-type drying furnace with good thermal insulation performance, including a burner, a stainless steel heat exchanger axial flow circulation fan, a drying room, air supply ducts, a circulating hot air filter and a drying oven automatic It is composed of exhaust gas device, and the products hanging on the conveyor chain pass directly through the drying chamber at a uniform speed. Whether the temperature in the bridge-type oven (curing furnace) is uniform or not depends on the air pressure of the thousand-cycle bad air, the air flow in the air supply pipe and the opening arrangement of the air supply pipe.

4. Ground chain support and conveying drive system of spraying production line
The coating section of the production line uses a ground chain conveyor line. The aluminum alloy wheels are placed on the ground chain support in the horizontal direction. A sprocket is installed in the middle of the support. When passing through the electrostatic automatic spraying section, the fixed chain drives the sprocket and drives the wheel to be placed on the horizontal The direction rotates around the center hole. The advantages of ground chain conveying workpieces. Central air supply is used in the thousand spray booths, and the leaves form an upper air supply and lower exhaust state in the spray booth. The grease and oil dust in the ground chain track and the large paint on the hanger will not fall off It can reduce the influence of spray particles; the running track of the ding piece is more stable than the suspension chain, which provides a good foundation for automatic painting.
5. Electrostatic automatic spraying system for spraying production line fixed gun tracking spraying
When the joint wheel load enters the entrance of the spray room, the workpiece detection system detects the workpiece information and sends a signal to the tracking spraying and screwing system. When the workpiece reaches the spraying position of the spray booth, the first set of 2 static electricity on the horizontal tracking reciprocating machine The air spray gun sprays the upper part of the wheel load, and the second set of 2 electrostatic air spray guns sprays the lower part of the wheel load. The spray gun tracks the spraying time, and adjusts it according to the actual conditions such as the process chain speed and the spraying effect. Finally, manual inspection is carried out, and local corners are manually painted to make the workpiece completely sprayed.
The moving speed of the horizontal tracking reciprocator is interlocked with the chain speed setting of the conveyor chain, and the traveling speed remains the same; when the conveyor chain is abnormal or in an emergency stop state, the automatic spraying system on the reciprocator can automatically reset after the spraying procedure is completed; connect the reciprocator The greater the degree of freedom of the fixed rocker arm with the electrostatic spray gun, the easier it is to adjust the spray angle of the spray gun. At the same time, the angle and position scales on each part of the rocker arm are easier to formulate the spraying process of each shape of the wheel.

6. Wastewater treatment system for spraying production line
The wastewater from the coating line is mainly the wastewater generated from the pre-treatment degreasing, passivation and paint spraying tanks. These wastewater contain acid and alkali, resin cured products and a small amount of organic substances such as toluene. The treatment equipment mainly includes the adjustment tank, dosing device, integrated tank, floatation device, mechanical filter press, adsorption device, sludge dewatering device and various valves, pumps, etc. After these equipments are processed according to a certain process, the coating line Waste water can meet the requirements of national discharge standards.
7. Other related auxiliary equipment of spraying production line
Other related auxiliary equipment of motorcycle aluminum alloy wheel ground-chain electrostatic automatic spraying line mainly include workpiece infrared radiation preheating system, conveyor chain automatic refueling system, power distribution cabinet, switch control cabinet, power cable, cable tray, and wind forced cooling device , Clean air supply device, exhaust gas discharge device, etc.