Over the years the company has adopted various methods for agitating paint in such massive tanks before mixing them in the requisite facility. Plate 1 was a view of the companys mixing room with drums of 200 to over 500-litre capacity containing paints of various color sheds that needed to be properly agitated each time before any paint fetch from them for blending in standard facility prior to painting. This typical problem was observed at Peugeot Automobile Nigeria (PAN) Limited factory at Kaduna. Defects such as color variation, loss of gloss, and low paint film thickness can therefore be found on painted surfaces if paints are not agitated in such tanks before dispensing them to standard facility for dilution and blending. Addition of excess or insufficient solvent affects the coloration, gloss, and the film thickness of the paint- finished surfaces after drying. To dilute the paint to obtain the requisite viscosity, solvent is added. The paint at the bottom of the tank will therefore require more dilution to obtain specified viscosity at its application temperature. Continued subsequent fetching of such remaining paint for mixing in the facility may not produce the paint with the requisite properties like colour, adhesion, viscosity and flow ability. Where the paint is kept fetching in that manner without agitation depending on the daily work need, the paint at the bottom of the tank tends to form sediments so that its properties such as viscosity are not the same with the original paint procured from the supplier. Mixed with additives in standard facility to obtain the requisite homogeneity and properties for painting. The paints are fetched therein the tanks from the tops and agitatedly In some plants, paints are acquired and kept in large massive drums or tanks in different colour sheds because of cost and handling advantages in external and internal logistics. Standard facilities are available for agitating limited quantities of paints in limited sizes of containers. Proper agitation of paint to obtain its desired consistent properties before painting is an important requirement in industrial and commercial paint applications so as to avoid myriads of costs associated with paintworks. Key words:- Massive paint tanks, color shed, requisite properties, improper agitation, human drudgery, standard agitators, color blends, paintwork defects, costs. The design is recommended to be used to develop the agitator to remove the drudgery of human folk in mix-homogenizing paint in massive tanks to desired consistent properties before blending it with additives in standard facility prior to painting to avoid inconsistencies in the requisite blend properties and consequent paintwork costs. The agitator can be fabricated by arc-welding the 40x40mm SHSS structural elements. The analyses indicated a structurally sound design with each SHSS frame section by comparison to acceptable limits for structural deflection and strength code. The worst case scenario using two 1700mm-longest structural elements of the frame treated as simply supported with half- weight of the tank uniformly distributed on each was used in the analyses. Operational deflections and stresses in the frame structures were analyzed using effective elasticity formulae with each SHSS section for overall integrity assessment of the agitator in service.
Three square hollow structural steel (SHSS) frame sections of 60圆0mm, 50x50mm, and 40x40mm and 3mm wall thickness were selected for the structural elements. The agitators feasible frame configuration and structural specifications were conceptually designed for supporting the paint tank with angle inclination of 22° in continuous rotation through 360o during the agitation time. Basically, the agitator was designed to consist of a steel supporting frame structure for the tank and a 50mm-diameter-90mm-long steel shaft gear-driven with a torque of 1800Nm by a 4-Hp electric motor. Guma, Anthony Agbata Department of Mechanical Engineering Nigerian Defence Academy,Ībstract-The paper presents the design of a mechanical agitator for efficiently mixing paint segments to consistent properties in sealed tank of total mass up to 200Kg without having any contact with the paint itself. Design of A Mechanical Agitator for Supplementing Paint Mixing with Standard Facilitiesĭr.
0 kommentar(er)
