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Advantages and disadvantages of nodular cast iron pipe fittings and installation specifications of nodular cast iron pipe fittings anti-corrosion treatment

Column:Technical article Time:2019-01-12

Advantages and disadvantages of ductile iron pipe fittings and installation specifications: 1. Advantages and disadvantages of ductile iron pipe fittings...

Advantages and disadvantages of ductile iron pipe fittings and installation specifications

1. Advantages and disadvantages of ductile iron pipe fittings: advantages: in the middle and low pressure pipe network, ductile iron pipe has the advantages of safe and reliable operation, low breakage rate, convenient construction and maintenance, fast, excellent anti-corrosion performance, etc.

Disadvantages: in high pressure pipe network, generally not used, low pressure resistance. Because the tube is relatively bulky, machinery must be used for installation. If water leakage occurs after the pressure test, all pipes must be dug out and hoisted up to the height of the clamp to prevent water leakage.

Installation specification of ductile iron pipes: the appearance of ductile iron pipes has provided a new type of pipes with excellent performance for China's water supply industry. In order to make better use of ductile iron pipes in engineering, designers and constructors should be familiar with the characteristics of ductile iron pipes, constantly find problems and solve them, so as to make the design more reasonable and construction more standard, and make new pipes play a greater role in water supply engineering.

Three-way harf joint plugging device, specially used for pipe three-way interface parts or three-way itself leakage when the rapid repair. The positive three-way leak stopper can repair the positive three-way made of various materials. The N25 flange ductile iron pipe coils and pipe fittings are usually made of ductile iron pipe, iron pipe, galvanized pipe, steel pipe, E pipe, VC pipe and other materials. Is a three - way Huffman joint plugging device for a variety of materials of three - way pipe sandhole, leakage, fracture and other problems, both convenient and cost saving method is to repair the pipeline rather than replace the three. The structure of the three-way leak-stopper is upper and lower structure, with natural rubber sealant pad inside. When using, align with the three-way part of the pipe and tighten the bolt. Three-way plugging device is easy to install, fast and cost saving, and is the first X "good medicine" in the emergency repair of pipe three-way fittings.

In addition, for reducing the size of the tee, can be customized to reduce the size of the three-way plugging device, for the pipeline medium corrosive three-way, can be customized stainless steel three-way plugging device, sealed fluorine rubber. Whether for water, steam, or chemical piping, a straight three-way plug is better than replacing the three-way itself.

Hough section stopper, also called tee patch, equal tee to repair, for cast iron shell, lined with rubber, mainly used for leak repair tee interface or tee itself, equal tee hough section, convenient installation, when tee is leaking, do not need water, direct encase with tee hough section original tee fitting, check leakage could be achieved.

Ductile iron pipe fittings type: K ductile iron pipe fittings, T ductile iron pipe fittings.

Ductile iron pipe fitting connection: flange, socket, socket

Standard for ductile iron pipe fittings under pressure: N10, N16, N25

Microstructure of nodular cast iron pipe: on ferrite and pearlite matrix distribution has a certain number of nodular graphite, according to the requirement of the nominal diameter and the elongation is different, the proportion of ferrite and pearlite in the matrix organization is different, small diameter of pearlite proportion is generally not more than 20%, the general control of large diameter is about 25%.

Anticorrosive treatment of ductile iron pipe fittings:

1. Asphalt paint coating

Bituminous paint coating is used to transport gas pipelines. Preheating the pipe before painting can improve the adhesion of asphalt paint and accelerate drying.

2. Cement mortar lining + special coating

This kind of internal anticorrosive measure is suitable for sewage pipeline, and can improve the corrosion resistance of lining.

3. Coal tar epoxy coating

Epoxy bituminous coating is suitable for both gas and sewage pipelines. It is a two-component coating with high adhesion and a very smooth surface