How to choose the quality conduit from China?
How to choose the quality flexible conduit from China? Electrical flexible conduit An electrical conduit is a tube used to protect and route electrical wiring in a building or structure. Electrical conduit may be made of metal, plastic, fiber, or fired clay. Most conduit is rigid, but flexible conduit is used for some purposes.Conduit is generally installed by electricians at the site of installation of electrical equipment. Its use, form, and installation details are often specified by wiring regulations, such as the US National Electrical Code (NEC) and other building codes.Flexible metallic conduit (FMC, informally called greenfield or flex) is made by the helical coiling of a self-interlocked ribbed strip of aluminum or steel, forming a hollow tube through which wires can be pulled. FMC is used primarily in dry areas where it would be impractical to install EMT or other non-flexible conduit, yet where metallic strength to protect conductors is still required. The flexible tubing does not maintain any permanent bend, and can flex freely.FMC may be used as an equipment grounding conductor if specific provisions are met regarding the trade size and length of FMC used, depending on the amperage of the circuits contained in the conduit. In general, an equipment grounding conductor must be pulled through the FMC with an ampacity suitable to carry the fault current likely imposed on the largest circuit contained within the FMC.Liquidtight flexible metal conduit (LFMC) is a metallic flexible conduit covered by a waterproof plastic coating. The interior is similar to FMC.Flexible metallic tubing (FMT; North America) is not the same as flexible metallic conduit (FMC) which is described in US National Electrical Code (NEC) Article 348. FMT is a raceway, but not a conduit and is described in a separate NEC Article 360. It only comes in 1/2" & 3/4" trade sizes, whereas FMC is sized 1/2" ~ 4" trade sizes. NEC 360.2 describes it as: "A raceway that is circular in cross section, flexible, metallic and liquidtight without a nonmetallic jacket."Liquidtight flexible nonmetallic conduit (LFNC) refers to several types of flame-resistant non-metallic tubing. Interior surfaces may be smooth or corrugated. There may be integral reinforcement within the conduit wall. It is also known as FNMC. Flexible conduit Material Thickness of steel Lock type Metal flexible conduit Hot or cold dip glavanized 0.15, 0.16, 0.18, 0.20, 0.25, 0.27, 0.30, 0.35, 0.40, 0.50, 0.60, 0.65mm Single lock or double lock PVC coated flexible conduit Hot or cold dip glavanized Single lock or double lock Liquid tight flexible conduit Hot or cold dip glavanized Single lock or double lock As market acception, normally client will choose different thickness of straps, and hot dip and cold dip process also influence the unit price. Galvanized steel flexible conduit Flexible metallic conduit is made by the helical coiling of a self-interlocked ribbed strip of aluminum or steel, forming a hollow tube through which wires can be pulled. PVC coated flexible conduit PVC coated flexible conduit is steel conduit coated PVC as insulation part also protect steel in wet weather area. It is normally with single locked type. Liquid tight flexible conduit Liquid tight flexible conduit is different with other flexible conduit, it used double locked type, and also outside coated PVC more thick then PVC coated flexible conduit, using for machine cable wire connector.