Manufacturer of ordinary grade 3pe anti-corrosion spiral steel pipe for water supply coated composite pipe

Description :

　　 Spiral welded pipe: It is made by rolling low-carbon carbon structural steel or low-alloy structural steel strip into a pipe blank at a certain angle of the spiral line (called the forming angle), and then welding the pipe seam together. It can produce large-diameter steel pipes with narrower strip steel. The specifications are expressed as outer diameter * wall thickness, and the welded pipe should ensure that the hydrostatic test, tensile strength, and cold bending performance of the weld meet the requirements. To ensure product quality, we have developed a comprehensive quality plan, on-site work procedures, and inspection and testing plans for raw material inspection, leveling inspection, butt welding inspection, forming inspection, internal welding inspection, external welding inspection, pipe cutting inspection, ultrasonic inspection, groove inspection, external dimension inspection, X-ray inspection, hydrostatic testing, and final inspection. Spiral steel pipe products are produced using Lincoln welding machines from the United States for fully automatic double-sided submerged arc welding. The spiral steel pipes produced comply with international GB/T9711 and petroleum and natural gas industry standards SY/T5037 and SY/T5040. The national petroleum and natural gas industry standards produce various steel grades of double-sided submerged arc welded spiral steel pipes with diameters ranging from 159mm to 3620mm and wall thicknesses ranging from 3.5mm to 25mm, as well as straight seam welded steel pipes with diameters ranging from 57mm to 630mm and wall thicknesses ranging from 3-16mm. Each spiral steel pipe production line is equipped with X-ray, ultrasonic, and static water pressure for full line automatic detection. Spiral steel pipes are widely used in water engineering. Spiral tube material: Q235A，Q235B,Q345B,L245，L360，X70，X800Cr13、1Cr17、00Cr19Ni11、1Cr18Ni9、0Cr18Ni11Nb、Q345、L245、L290、X42、X46、X70、X80. Spiral pipe types: dredging spiral steel pipe, mud conveying spiral steel pipe, gas conveying spiral steel pipe, oil conveying spiral steel pipe, well drilling spiral steel pipe, pile driving spiral steel pipe, column spiral steel pipe, well drilling spiral steel pipe, flower pipe, advertising board column spiral steel pipe, water gas conveying spiral steel pipe, anti-corrosion and insulation spiral steel pipe, chemical spiral steel pipe, etc. For the convenience of customers, we can process steel pipe anti-corrosion, steel pipe insulation, pipe end flange welding and other services locally.

　　 Spiral pipe, also known as spiral steel pipe or spiral welded pipe, is made by rolling low-carbon structural steel or low-alloy structural steel strip into a pipe blank at a certain angle of the spiral line (called forming angle), and then welding the pipe seam together. It can produce large-diameter steel pipes with narrower strip steel.

　　Common standards for spiral pipes: SY/T5037-2000 (departmental standard, also known as spiral seam submerged arc welded steel pipes for ordinary fluid transportation pipelines), GB/T9711.1-1997 (national standard, also known as technical delivery conditions for oil and gas industry transportation steel pipes: Grade A steel pipes (GB/T9711.2 Grade B steel pipes with strict requirements)), API-5L (American Petroleum Institute, also known as pipeline steel pipes); It is divided into two levels: PSL1 and PSL2. SY/T5040-92 (spiral seam submerged arc welded steel pipes for piles).

　　Spiral seam submerged arc welded pipe for pressurized fluid transportation: mainly used for pipelines transporting oil and natural gas. Steel pipes have strong pressure bearing capacity, good plasticity, and are easy to weld and process into shapes; Spiral seam submerged arc welded steel pipes for general low-pressure fluid transportation: Submerged arc welded steel pipes made by double-sided automatic submerged arc welding or single-sided welding method for general low-pressure fluid transportation such as water, gas, air, and steam.

　　With the progress of the times, the types of pipes used for water supply and drainage in the construction industry are constantly improving and evolving. The plastic coated steel pipes we refer to here specifically refer to the steel plastic pipes produced by Xinhantong Pipe Industry that are coated with epoxy resin both inside and outside, while ductile iron pipes are commonly known as pipes made by high-speed centrifugal casting using cast iron of grade 18 or above with the addition of a spheroidizing agent through a centrifugal ductile iron machine. After continuous practical testing and verification, it has been found that compared with ductile iron pipes, coated pipes have the following advantages:

　　1. Plastic coated pipes have high hardness

　　Ductile iron generally has a large diameter, thick pipe wall, brittle texture, and low hardness. The hardness of ductile iron pipes is HB ≤ 230, while the hardness of coated pipes is between 275-320. Special attention should be paid to the anti breakage and anti damage of cast iron pipes during transportation and installation, and protective materials should be used to wrap both ends. The two ends of the large-diameter plastic coated pipe only need to be slightly packaged to ensure the coating of the ports.

　　2. Plastic coated pipes have high pressure resistance

　　Cast iron pipes, due to their low pressure resistance, are generally not suitable for high-pressure pipelines and can only be used for medium and low-pressure pipelines, such as sewage pipelines and urban sewage pipelines. However, coated steel pipes have stable pressure resistance and a wider range of applications, which can be widely used in industries such as chemical, pharmaceutical, food, petroleum and fire protection.

　　3. Plastic coated pipes have a long service life

　　The service life of ductile iron pipes is usually between 20-35 years, while the service life of steel plastic composite pipes can reach more than 50 years, greatly reducing the cost of pipeline re laying.

　　4. Plastic coated pipes are easy to install

　　Due to its high specific gravity, ductile iron pipes are relatively bulky and require the use of machinery for installation. And during installation, it is necessary to polish, modulate interface materials, twist joints, and maintain them. The construction work is not only heavy, but also the installation time is long, which significantly reduces the construction efficiency.

　　If used for domestic water transportation, after installation and pressure testing, it should be rinsed with low chloride ion water and disinfected with 0.03% potassium permanganate solution. After disinfection, the water quality of the sampled water must meet the standard before operation. If the socket connection method is adopted, the support pier should also be designed. The process is cumbersome and inefficient.

　　Plastic coated pipes, on the other hand, are easy and fast to install. Due to the unique properties of their steel body, they can be customized to produce matching fittings such as elbows, flexible joints, and tees with suitable pipe diameters according to the actual construction requirements on site. They can be installed in place in one go during installation.

　　5. The coating (EP) of plastic coated pipes has strong chemical stability

　　Ductile iron pipes generally use asphalt paint outer coating (to isolate the pipe wall from the external medium), special coating for cement mortar inner lining (generally only applicable to sewage pipelines), epoxy coal tar coating (for gas and sewage, with low pressure bearing capacity), epoxy ceramic inner lining (difficult manufacturing process and high cost), aluminate cement coating or sulfate cement coating (suitable for anti-corrosion inside sewage pipelines). Comparing the performance of these coatings comprehensively, their acid and alkali resistance, as well as their resistance to the solubility of petroleum products, are inferior to heavy-duty anti-corrosion epoxy resin coatings. The modified epoxy resin powder with heavy anti-corrosion properties has undergone salt spray test, cathodic peel test, chemical corrosion resistance test, and adhesion test, and the test results meet the requirements.

　　Choose galvanized and epoxy asphalt coatings based on the soil conditions of the external pipeline, as both have lower resistance to external corrosion than epoxy resin coatings for plastic coated pipes. Cast pipes that are only coated with asphalt protection without a zinc layer, once the coating surface is damaged, will form an electrochemical corrosion anode, causing local pitting corrosion. However, the combination of galvanizing and asphalt protection greatly delays the production cycle and wastes time.

AfterSalesService :

• Coated composite pipe