Days ducts is China's leading large southern district nursing care line cable ducts days manufacturer, has 10 years of experience in the development and production of galvanized pipe, tank and accessories areas, capacity, output and market share of three According to the forefront of the Southern Region index position. Mechanical properties of galvanized pipe ③ Elongation: (σ) in the tensile test specimens which gauge the increase in the percentage of the length of the original gauge length of the pull-off, called elongation. With σ expressed in units of%. Where: L1-- specimen fractured gauge length, mm; L0-- original specimen gauge length Guangdong days ducts, mm. ④ Reduction of area: (ψ) in the tensile test, the sample to reduce the percentage of the maximum amount of the original cross-sectional area of ??its cross-sectional area of ??the reduced diameter at the pull-off, known as section shrinkage. Ψ expressed in units of%. Where: S0-- original specimen cross-sectional area, mm2; S1-- specimen fractured necking at a minimum cross-sectional area, mm2. ⑤ hardness index: metal material to resist indentation capacity hard objects surface, called the hardness. Depending on the test methods and scope, can be divided into Brinell hardness, Rockwell hardness, Vickers hardness, Shore hardness, micro-hardness and high temperature hardness. Pipe commonly used for Brinell, Rockwell, Vickers hardness of three. A, Brinell hardness (HB): test force (F) with a certain diameter steel balls or carbide ball days ducts specifications prescribed pattern pressed into the surface, the provisions of hold time after removing the test force measurement sample surface indentation diameter (L). Brinell hardness test force is divided by the surface area of ??the resulting indentation spherical providers. With HBS (ball), said unit N / mm2 (MPa). Classification Features hot galvanized pipe with a galvanized coating uniformity, strong adhesion, long life and other advantages. Steel substrate and the molten bath complicated physical, chemical reaction, the formation of corrosion-resistant compact structure of zinc-iron alloy layers. Alloy layer and the pure zinc layer, integrated steel substrate. So its resistant to corrosion. 1, the uniformity of the zinc coating: steel samples immersed in a copper sulfate solution five times in a row may not turn red (copper color) 2, surface quality: galvanized steel surfaces should have a complete zinc coating shall have not plated spots and bubbles exist, allowing little rough surface and the presence of localized tumors zinc. 3, zinc coating weight: According to the requirements days galvanized pipe, galvanized steel pipe can be used for measuring the weight of the zinc layer, the average value of not less than 500g / square meter, of which not less than any sample 480g / sqm. Galvanized steel is widely used in construction, machinery, coal, chemical, railway vehicles, the automotive industry, roads, bridges, container, sports facilities, agricultural machinery, petroleum machinery, mining machinery and other manufacturing industries. Guangdong days ducts and ducts _ _ days days all kinds of ducts and ducts direct bridge provided by the steel bridge, Ltd. Guangdong days. Guangdong days steel bridge Limited (www.nhtianlai.com) strong, credible, in Foshan, Guangdong steel industry has accumulated a large number of loyal customers. The company better work attitude and constantly improving innovative ideas will lead the day to ducts and you hand into the brilliant, for a better future!