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HAH has provides Phosphate coating on the thread connection.

• Phosphating (or phosphatizing) is a surface treatment used on steels to prevent corrosion, enhance the surface for other protective coatings, or for lubricity.

• It is formed by creating a layer of crystal salts of iron and zinc or iron and manganese in a phosphoric acid solution.

• Most common uses of phosphating are related to carbon steels, cast iron or to high and low strength alloy carbon steels.

• Phosphatizing can be achieved by immersing the part into a bath or by spraying the part with the phosphating solution. A chemical reaction takes place that causes the zinc (or manganese) phosphate salts to adhere to the part surface.