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Discussion On Four Reasons Of Valve Casting Turning Black

Ningbo Qianhao Metal Product Co.,Ltd | Updated: Jun 19, 2017

  Discussion on four reasons of valve casting turning black

  In the field of machining, because of the particularity of the valve castings, there will be the appearance of the black phenomenon in the process of use. What is the reason for this?

  1. Internal reasons. Many of the valve casting manufacturers in the die-casting, machining, will not do any cleaning work, and some even simply water dash, these are difficult to complete clean. And the surface of the die casting agent, cutting fluid, saponification liquid and other corrosive substances and other stains, will accelerate the casting mold black speed.

  2. The impact of the external environment. In a certain temperature and humidity conditions, the casting will be very easy to appear oxidation black or moldy situation, in fact, this is determined by the characteristics of the casting itself.

  3. Unreasonable process design. Valve castings in the cleaning or pressure after the treatment of improper, will give the casting moldy, black to create a certain condition, accelerate the formation of mildew. And if the choice of cleaning agent has strong corrosive, it may also cause corrosion and oxidation of castings.

  4, warehousing management is not in place. The casting is stored in the different heights of the warehouse, and its mildew is different.