In the electroplating process, the titanium hanger mainly functions as a conductive, supporting and fixing part, so that the part can obtain a uniform current in the plating tank as much as possible. Therefore, designing and making reasonable hangers is of great significance for ensuring product quality, improving production efficiency and reducing costs. The following principles must be mastered when designing and selecting hangers: First, the selection of titanium hanger materials and insulation materials should be reasonable, and the structure should ensure the uniformity of coating thickness; second, it must have good electrical conductivity and meet the process requirements. Third, it is convenient to operate between the titanium hanger and the parts, which is beneficial to increase productivity. For more information, please click “How to Reduce Corrosion Methods for Titanium Hangers”.
(1) Forms of general titanium hangers and materials used
The form and structure of the universally-plated titanium hanger should be determined according to the geometry of the plating, the technical requirements of the coating, the process and the size of the equipment. For example, the sheet-like plated member may float with the resistance of the plating solution between the upper and lower processes, and the plated member is clamped or tied with a copper wire when the hanger is selected. If the plated part is heavy and has holes, a hook-shaped hanger can be used. For example, the bicycle rim is round, and as long as the inside is plated, a larger clamp is used to clamp the outside of the rim.
Common fixtures are mostly used for plating that is not too thick, allows parts to sway in the plating tank, and has a low current density, such as galvanizing, cadmium, tin, copper, nickel, and the like. Universal hangers are generally composed of five parts. These five parts can be welded into a fixed type, and the hooks and struts can be made into an adjustable assembly. The effects of free space and power lines should be considered between parts and parts during plating. To make the coating uniform, a certain distance must be maintained. If the form and structure of the titanium hanger is not properly selected, it will affect the quality of the coating.
In short, the form of the titanium hanger must depend on the shape of the plated part and the surface to be plated. Whether the selection of the form and structure of the titanium hanger is reasonable in electroplating, and whether the use of the material is appropriate will directly affect the product quality and production efficiency.
(2) Calculation of the cross-sectional area of titanium hangers
The size of the cross-sectional area of the titanium hanger is very important. If the cross-sectional area of the titanium hanger is too small, it takes a long time to make the thickness of the coating meet the requirements. If the cross-sectional area is too large, it will result in waste of materials, so the calculation of the cross-sectional area of the titanium hanger should be reasonable.
(3) The use of titanium hangers requires good contact between the hanger and the cathode rod, which is critical to the quality of the plating, especially in the case of high-current hard chrome plating and decorative plating using cathode moving agitation, often due to poor contact. The contact resistance is generated to make the current not smooth. Therefore, intermittent power failure occurs, causing poor bonding strength of the plating layer, and also affecting the thickness of the plating layer, resulting in a decrease in corrosion resistance. It is therefore required to maintain a clean and good contact of the contact points between the titanium hanger and the cathode rod during processing of the hanger and the use. The cross section of the guide rod is usually round and rectangular, and the suspension method is required to design the hook.
(4) Insulation of titanium hangers, cnc machining
The main and struts of the titanium hanger are immersed in the plating solution during electroplating. During the electroplating, the titanium hanger and the plated part are subjected to the same process of electroplating. If the titanium hanger and the plating solution are not insulated, the plating area will be enlarged, thereby reducing the current density, prolonging the plating time, wasting energy and metal materials, and increasing the plating cost. Therefore, the insulation of the titanium hanger is very important. It is required that the insulating material can withstand high temperature during electroplating, does not affect the composition of the plating solution, and is not damaged for a certain period of time.
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