There are five coloring methods for stainless steel flanges:
1. Chemical oxidation coloring method;
2. Electrochemical oxidation coloring method;
3. Ion deposition oxide coloring method;
4. High temperature oxidation coloring method;
5. Gas phase cracking coloring method.
A brief overview of various coloring methods is as follows:
1. Chemical oxidation coloring method is to form the color of the film through chemical oxidation in a fixed solution, including complexing acid salt method, mixed sodium salt method, sulfurization method, acid oxidation method and alkaline oxidation method. In general, “INCO” method is used more frequently, but to ensure the uniform color of a batch of products, reference electrodes must be used for control.
2. Electrochemical oxidation coloring method: It refers to the color of the film formed by electrochemical oxidation in a specific solution.
3. Ion deposition oxide coloring method: put the stainless steel flange workpiece in the vacuum coating machine for vacuum evaporation plating. For example, the titanium plated watch case and band are generally golden yellow. This method is suitable for processing large quantities of products. Because of large investment and high cost, small batch products are not cost-effective.
4. High temperature oxidation coloring method: It is used to immerse the workpiece in a specific molten salt to maintain a certain process parameter, so that the workpiece can form an oxide film of a certain thickness and show a variety of colors.
5. Gas phase cracking coloring method: this method is more complex and less used in industry.
（The above figure shows an example of welding neck flange）
The stainless steel flanges used for a long time shall be inspected on schedule. The exposed processing surfaces shall be kept clean and cleaned of dirt. They shall be neatly stored in ventilated and dry places. Stacking or open storage is strictly prohibited. Keep the stainless steel flange dry and ventilated, keep it clean and tidy, and store it according to the accurate storage method. During installation, the stainless steel flange can be directly installed on the pipeline according to the connection mode and installed according to the use position.
Generally, it can be installed on any position of the pipeline, but it is necessary to facilitate the inspection of operation. Note that the medium flow direction of the stop stainless steel flange should be upward under the longitudinal valve flap, and the stainless steel flange can only be installed horizontally. During the installation of stainless steel flanges, attention shall be paid to the tightness to prevent leakage from affecting the normal operation of the pipeline. As stainless steel has good corrosion resistance, it can make structural components permanently maintain the integrity of engineering design. Stainless steel flanges will not have corrosion, pitting, rust or wear
Chromium containing stainless steel flange also integrates mechanical strength and high extensibility, which is easy to process and manufacture components and can meet the needs of architects and structural designers. All metals react with oxygen in the atmosphere to form a hydrogen film on the surface. If holes are formed, paint or oxidation resistant metal can be used for electroplating to ensure the carbon steel surface. However, as we know, this protection is only a film.
Post time: Dec-01-2022
