【Weekly Topic】2.8~2.14 Powder Electrostatic Spraying (Automatic +5 points for replies; +3-10 points for financial analysis)

What are the essential equipment items for powder electrostatic spraying? 1. Compressed air ； Oil-water separation and cold air drying are required. 2. Electrostatic spray gun ； Including an electrostatic generator and a powder supply tank. 3. Spraying booth (room) ； It comes with a collection device to prevent powder from scattering everywhere. 4. Oven or drying tunnel ； High temperature causes the powdered coating to cure into a film. 5. Conveying chain ； During assembly line operation, the chain moves to spray the product. The bread oven only requires a frame to hold the sprayed products. 6. Pretreatment ； Medicine tank or spraying equipment.

What are the essential equipment items for powder electrostatic spraying? Answer: The main equipment for powder electrostatic spraying includes: (1) a spray gun and an electrostatic controller. In addition to the traditional built-in electrode needle, the spray gun is equipped with an annular corona, which helps to make the electrostatic field more uniform and thus ensures a consistent thickness of the powder coating. The static controller generates the required high static voltage and maintains it stable, with a fluctuation range of less than 10%. (2) Powder supply system The powder supply system consists of a new powder tank, a rotating sieve, and a powder delivery tank. The powder coating is first added to the new powder tank; compressed air causes the powder to be pre-fluidized through the micropores in the fluidization plate at the bottom of the tank, and then it is transported to the rotary sieve via a powder pump. The rotary sieve separates out powder particles with an excessive particle size (100 μm and above), while the remaining powder falls into the powder supply tank. After fluidizing the powder to the desired degree, the powder supply tank feeds it to the spray gun through a powder pump and powder delivery tube for spraying on the workpiece. (3) Recovery system: Apart from a portion of the powder emitted by the spray gun that gets adsorbed onto the surface of the workpiece (usually 50%–70%), the remaining portion settles naturally. During the settling process, a portion of the powder is collected by the cyclone collectors located on the side walls of the powder spraying booth; these collectors use the principle of centrifugal separation to isolate larger powder particles (12 μm and above) and send them back to the rotating sieve for reuse. Powder particles of 12pom or less are sent to the filter element collector, where the powder is shaken down by pulsed compressed air into the collection bin at the bottom of the filter element; this powder is then regularly cleaned, packaged, and prepared for sale. Clean air from which the powder has been separated (with powder particle sizes of less than 1 μm and a concentration of less than 5 g/m3) is discharged into the powder spraying chamber to maintain a slight negative pressure inside it. Excessive negative pressure can easily draw in dust and impurities from outside the powder spraying chamber, while too low negative pressure or positive pressure can lead to powder leakage. The powder that settles at the bottom of the powder spraying booth is collected and then fed back into the rotary sieve via a powder pump for reuse. The mixing ratio of recycled powder to new powder is (1:3) to (1:1). (4) The top and side panels of the powder spraying chamber are made of light-transmitting polypropylene plastic, in order to minimize powder adhesion and prevent the accumulation of static charges from interfering with the electrostatic field. The bottom plate and base are made of stainless steel, which facilitates cleaning and provides sufficient mechanical strength. (5) Auxiliary systems include air conditioners and dehumidifiers. One function of the air conditioner is to keep the powder spraying temperature below 35°C in order to prevent the powder from caking ； Secondly, a slight negative pressure in the powder spraying chamber is maintained through air circulation (wind speed less than 0.3 m/s). The function of the dehumidifier is to maintain the relative humidity in the powder spraying chamber at 45%–55%. If the humidity is too high, discharge can occur, leading to the breakdown of the powder coating; if it is too low, the conductivity is poor and ionization becomes difficult.

Essential equipment for powder electrostatic spraying includes: 1. Air compressor (to provide compressed air); 2. Electrostatic spray gun; 3. Spraying booth; 4. Oven or drying tunnel; 5. Conveying chain; 6. Pretreatment (chemical bath or spraying equipment).

1. Compressed air； Oil-water separation and cold air drying are required. 2. Electrostatic spray gun ； Including an electrostatic generator and a powder supply tank. 3. Spraying booth (room) ； It comes with a collection device to prevent powder from scattering everywhere. 4. Oven or drying tunnel ； High temperature causes the powdered coating to cure into a film. 5. Conveying chain ； During assembly line operation, the chain moves to spray the product. The bread oven only requires a frame to hold the sprayed products

A powder electrostatic spray gun is mainly composed of a powder supply tank, a spray gun, and a controller.

Electrostatic spray gun, high-voltage electrostatic generator

Powder electrostatic spray gun (spray gun control device), recovery device, powder room, and powder supply device, etc

1 Spray gun and static controller, 2 Powder supply system, 3 Recovery system, 4 Powder spraying chamber body

Surface treatment equipment, electrostatic powder coating equipment, powder recovery equipment