Welded pipe production and three classifications

Today, hot-dip galvanized steel pipe is a common type of fire protection pipe and plays an irreplaceable role in the fire safety industry. Why can't hot-dip galvanized pipes be replaced by cheaper welded pipes or cold galvanized pipes?

Hot-dip galvanizing was invented in the middle of the 18th century and developed from the thermoelectric tinning process, which has a history of more than 300 years. Until today, hot-dip galvanizing is still a widely used and effective process countermeasure for steel corrosion resistance.

General welded pipe:

General welded pipe is used to transport low-pressure fluids. Made of Q195A, Q215A, Q235A steel. Can also be easy to weld other soft steel manufacturing. Steel pipe to water pressure, bending, flattening and other experiments, there are certain requirements for surface quality, usually delivery length of 4-10m, often require fixed-foot (or times the foot) delivery. Welded pipe specifications expressed in nominal caliber (millimeters or inches) nominal caliber is different from the actual, welded pipe according to the specified wall thickness of ordinary steel pipe and thickening of two kinds of steel pipe according to the form of the pipe end and divided into two kinds of threaded and unthreaded.

Galvanized steel pipe:

In order to improve the corrosion resistance of steel pipe, the general steel pipe (black pipe) galvanized. Galvanized steel pipe is divided into hot-dip galvanized and electric steel zinc two kinds of hot-dip galvanized galvanized layer is thick, electric galvanized low cost.

Metric welded pipe:

Specifications used as a seamless pipe form, expressed in millimeters of outer diameter wall thickness of welded steel pipe, with ordinary carbon steel, high-quality carbon steel or universal energy low alloy steel hot strip, cold strip welding, or hot strip welding and then made by cold dialing method. Metric welded pipe is divided into universal and thin-walled, ordinary used as structural parts, such as drive shafts, or to transport fluids, thin-walled used to produce furniture, lamps and lanterns, etc., to ensure that the steel pipe strength and bending test.

Also due to the same reason, the hot galvanized pipe coating closely, the adhesion of the galvanized layer is better than the cold galvanized pipe, adhesion is high on behalf of the galvanized layer is not easy to be destroyed due to the delivery of the whole process of the impact of friction.

Hot-dip galvanized steel pipe in the production of the whole pipe is immersed in galvanized pool galvanized, so all exposed surface can be coated with zinc, while cold galvanized steel pipe is usually used in the production of a zinc-coated thick steel coil rolled welded into the weld, in the weld of the pipe, there is no galvanized layer of protection. So we will choose compared to the more secure and durable hot-dip galvanized steel pipe.