Our factory has used electrostatic painting technology for fifteen years. We have also conducted two large-scale technological transformations in the middle of the plant and have realized a fully automated production line. Then, the cleaning equipment before steel drum painting was reconstructed, which greatly improved the coating quality on the outer surface of steel drums and was well received by users. However, with the increasingly fierce market competition and the continuous improvement of user requirements, the quality of the steel drum coating in our factory has also appeared some problems that cannot meet the requirements of users. At the beginning of the year, the user raised the problem of paint on the bottom of the barrel. Through careful analysis and processing, the quality problem was satisfactorily solved. The user was very satisfied and said with pleasure: “It is not the same, it is not the same!â€
I. Analysis of the causes of quality problems
The phenomenon caused by quality problems is: After the paint drying, the surface of the bottom of the steel drum can often be found to have a piece by piece of paint, affecting the appearance of the outer surface, and these paints are as few as three or two, and as many as ten. At different sizes, it usually presents 5 to 10 mm convex dots.
In order to find out the cause of the problem, we carefully investigated the process from the beginning of painting of steel barrels to the drying of the barrels. We found that the problem of accumulated paint on the bottom of the barrel was caused by the following reasons: In the painting room, due to the spray nozzles The paint fog is continuously adsorbed on the guide rails and racks. After excessive absorption, it flows downwards from the racks and racks or drops. The paint drips on the bottom of the bucket and forms a raised product after drying. Paint spots.
Briefly, our painting method is electrostatic painting. The steel drum conveying method is chain suspension conveying. The steel drum is upright and enters into the “Ω†shape spray chamber for painting. The steel drum is gripped by the three-jaw hanger on the bottom flange of the bucket. The rotation of the steel drum in the spray booth is based on the transmission of the guide rail gear on the hanger and the “Ωâ€-shaped rack in the spray booth. The spray disc is located in the center of the spray chamber, and is driven by the pneumatic motor to rotate and move up and down under the action of the cylinder. The stroke of movement is slightly larger than the height of the steel drum so that the top of the steel is affixed with paint.
Second, the method of solving the quality problem test
In order to solve the problem of paint on the bottom of the bucket, we have taken a series of measures to carry out the test. The test methods and results are as follows:
1. In order to solve the problem of paint dripping with hangers, we implement two sets of methods for timed replacement of rigs. Because each time the hanger passes through the paint booth, it will draw on the paint, but after drying, it will solidify on the hanger. Only when the paint on the hanger is large in thickness and there is an underflow nozzle, can the paint be drip normally. In the production situation, replacing one rack can produce about 10,000 barrels.
2. The paint on the paint rack indoor rack is not dripping because it is not dried. The newly treated rack sprays less than 200 barrels, which means that there is a phenomenon of dripping paint. In order to make the rack not lacquer, it is necessary to find ways to make the paint not adsorb onto the rack. Starting from this goal, we first lengthen the length of the hanger so as to reduce the height of the barrel during painting and reduce the highest point of the spray plate at any time. In this way, the frontal contact of the paint mist and the rack is avoided, and the rack suction is reduced. Paint, but the effect is not complete, because there is always a scattering of paint mist, the problem of lacquer has not been completely resolved.
3, in order to reduce the paint mist flying upward to reach the rack, we set a plastic plate cover on the spray plate at 150 mm, reducing the paint fog. After the test, it was found that the rack paint was significantly reduced, and 400 to 500 barrels could be produced before the racks began to drip. However, the racks could not be lacquered, and satisfactory results could not be achieved.
4, in order to better reduce the paint mist to the rack adsorption, we also placed a baffle between the rack and the spray plate, baffle plate made of plastic, and bent into a shape corresponding to the rack "Forms. After trials, although the lacquer of the rack was greatly reduced, paint mist adsorbed on the baffles began to lacquer after a period of production, confirming that the effect was not satisfactory.
5. Through the above tests, we have realized that, in order to completely solve the problem of paint coating on the bottom of the bucket, it is obviously impossible to create obstructions on the existing equipment to prevent the paint from rising. For this reason, we tried to change the method of rotating the drum in the paint booth and remove the structure of the rack drive. We studied the inertial rotation method, that is, when the steel drum is about to enter the spray booth, the electric drum is used to rotate the steel drum. After entering the spray booth, inertia is applied and the steel drum has not stopped rotating until after spraying. Out of the spray booth, the drum stopped slowly. This method works well and directly prevents the rack dripping.
Third, conclusions and feelings
Through a large number of experiments and analysis, we finally found a better solution: We adopted two sets of hangers to periodically replace the solution to solve the problem of hanging paint dripping; the use of steel barrel inertial rotation method to replace the rack drive structure, solved Dripping paint problem.
From this small reforms, we realized that in order to solve problems, we must not only stay in the existing conditions, do not be afraid of difficulties, and do not have the thoughts of perfunctoring and dealing with errands. To be more broad-minded, we must dare to break the status quo. Only in this way will there be more and better ways to solve the problem.
Flexible lift gate is a flexible soft curtain door, inside and outside the two curtains, curtains used between the aluminum beams connected with a vertically movable rail, the roof beams have levels not in the same straight line and hangar large plants in particular be applicable. Flexible lift door installation does not take up interior space in the hole inside. When the fiest move to open the door, and finally superimposed over the hole. Off event curtain rail first and then fall down until it is completely closed.
Flexible Gate,Flexible Pvc Aircraft Folding Up Door,Steel Structure Fabric Flexiile Door,Exterior Automatic Flexible Door
Shenzhen Hongfa Automatic Door Co., Ltd. , https://www.highspeedshutterdoor.com