Design of a dispensing system for powder coating

Abstract

Fast & Fluid Management is a world leader in POS (Point of Sale) dispensing and mixing systems for the paint industry. PPG Industries, the largest powder coat supplier in the world, approached F&FM to develop a powder dispenser for their newly developed coatings- Vivati®. PPG wants to be the first to offer the powder coating industry a unique and extremely valuable means of creating and dispensing custom powder coats at the Point of Use. This patented nanotechnology powder has the particle characteristics to allow blending, something not attainable by traditional powder coats. The F&FM dispenser will allow users to create color recipes and accurately, and repeatability, dispense the powder recipes prepared for spraying. F&FM wants to strengthen and broaden their product portfolio. Therefore a feasibility study was carried out to verify the technical and economical feasibility of a new powder dispenser; the price of the system cannot exceed € 5000. The powder dispenser is based on a proven dispense technology, implemented in a new application. The dispenser can disperse powder in amounts as minimal as 0.1 grams to a maximum of 5000 grams within 15 minutes or less. The dispenser is equipped with thirteen 20-liter canisters for each base color. The canisters are mounted on a turning table, which rotates to the forward position to dispense into a holding canister each color in the recipe. The user is able to simply fill or refill the canisters with a specially developed packaging bag. The sealed bags allow the user to refill the canister without cross-contaminating the powder. The closed bag connector allows for a clean refilling process. The feasibility study is positively ended; it is feasible to dispense 0.1 gram, and to dispense 500 gram powder in 15 minutes. These findings are the result of tests with a functional model. The cost estimation of the powder dispenser showed that it is feasible to develop this system for a cost price of €4637. The following aspects making the designed powder dispenser innovative for F&FM and the dispense market: -The mechanical dispensing working principle is a proven technology. Implementing this technology in a new application, risks of failure are extremely reduced. The simplicity of the technology is it strength: A dosing valve is rotated and because of translational movement at the same time, an opening is created for the powder to flow out. By varying the rotation speed and the size of the opening, the flow rate of the powder is controlled. The technology appropriate for this application since: o The powder can be dispensed with high accuracy, o The customized colors can be dispensed time after time (repeatability), o A large volume range of powder can be dispensed: 100-5000 grams. The existing turntable principle being utilized by F&FM is renewed with this new system; the table is positioned at the top of the dispenser, the canisters are positioned underneath the table. This new turning table concept has multiple advantages: o Thirteen canisters together form a part of the housing of the machine. Since the canisters are positioned closely to each other, they form a solid and secure unit. Hereby, additional housing is not required, resulting in a cost savings. o The canisters can be easily placed, filled, cleaned or taken out for maintenance. o The open space between the canisters in the new dispenser is used. F&FM’s current designed dispensers use this space in-efficiently. By positioning components in the space, the entire dispenser is more compacted and less housing material is needed. The result is a cost saving for the system. Additionally, a compact machine is advantageous to the owner because less shop-space is required. o Since the powder is combustible, extra safety adaptations are applied. The powder dispenser is open at the bottom of the unit; hereby no powder and dust to build-up can occur in certain system regions. o If powder would be spilled during handling, it falls on the ground because of the open structure of the system. Since the powder falls in an open area, no dangerous explosion situations would be created. The project will continue with the build of an alpha prototype. This model will be used by the client for test purposes.