How to choose a ductile cast iron pipe with guaranteed quality
1, first of all choose the regular manufacturers of ductile iron pipe products.2, the choice of ductile iron pipe, should be based on the specific circumstances of the construction site, select the pipe and fittings corresponding to the form of interface.3, rubber rings recommend the use of three yuan ethylene propylene rubber ring and so on.4, listen to the voice, knocking the iron: short duration. The iron ball: crisp sound, echo, short duration5, the cutting surface is gray: gray, shiny surface seems very dark, very rough. Ductile iron: gray, gray luster is bright, like gray surface roughness.
Cutting testing: iron filing resistance, filing issued a "Shua" sound, little sticky file, debris was gray with a small amount of white spot, look at the particles of different size, with small particles of fine powder, finger milling, it is easy to make fingers black. Ductile iron filing: when the resistance ratio of gray iron is slightly larger, there are obvious "Shua" sound ", little sticky file, debris was gray with fine bright particles ranging in size but with large particles, with finger milling chips, can be dyed black to gray fingers, but more black the degree of light