The mill tolerance for welded pipe
1.The spiral steel: spiral steel coil as raw materials is steel, often warm extrusion, with automatic double- wire submerged arc welding process double- sided spiral welded steel pipe;
2. Standard: GB/T9711.1, API 5L, ASTM A53, ASTM A500, ASTM A672, ASTM A515 etc;
3. Materials: Q235, Q345B, GR.B, X42, X56, ST35, ST52, S235JR, Gr.60, Gr.65, Gr.70, SS400 etc;
WT: 4mm – 40mm;
Length: 6m – 18m;
5. End: plastic cap in the both end, pipe clamp;
6. Surface: Oiled, black painted or varnish, galvanized, 3PE, FBE, or other epoxy coating.
7. Inspection: Hydrostatic testing, ultrasonic testing, X-ray inspection.
8. Application: Bridges, construcion, water, oil and chemical industry & nbsp;
9. Spiral steel pipe pile principles and requirement:
1). The spiral pipe stacking principle requires that at palletizing firm to ensure the safety of the premise, to do according to species, size palletizing, different varieties of materials to be separately palletizing to prevent muddy and mutual erosion;
2). Do not store the erosion of steel have items in place around the spiral steel pipe pile;
3). Spiral Pipe pile bottom should elevate, firm, smooth, damp or prevent material deformation;
4). The same material has separately by stacking storage;
5). The open dumps spiral pipe steel, the following must have wood or stone pad, pile surface is slightly inclined to facilitate drainage, and pay attention to the material placed flat to prevent the causing bending deformation;
6). spiral steel stacking height, artificial homework does not exceed 1.2m, mechanical homework does not exceed 1.5m, pile width not exceeding 2.5m;
7). It should leave some passages between the stacks and stacks 7. Check road is generally 0.5m, of access depending on the size of the material and transport machinery, generally of 1.5 ~ 2.0m;
8). open dumps angles and channels should stoop to put that mouth down, I-beam shall stand up, I can not groove surface of steel up to avoid stagnant water rust;
9). pile bottom booster, if the warehouse is sunny concrete floor, can elevate 0.1m; if the mud, to be boosted 0.2 ~ 0.5m. If it is open space, concrete floor booster 0.3 ~ 0.5m, mud face booster 0.5 ~ 0.7m.
10. 2PE/ 3PE anti-corrosion and single-layer PE anticorrosive
1) 3PE anticorrosive:
Three-layer structure of PE pipe corrosion: the first layer of powder epoxy (FBE> 100um）,the second layer of adhesive ( AD) 170～250um, a third layer of polyethylene (PE) 2.5～3.7mm. Three materials integration, and with the steel firm to form an excellent coating.
Diameter range of Φ60～Φ14202) 2PE anti-corrosion steel pipe:
PE pipe corrosive story structure, the first layer of adhesive(AD), a second layer of polyethylene (PE), the same as the standard blend of two materials, the thickness of layers with three PE: SY/ T0413-2002 buried steel pipeline polyethylene coating technology standards GB/ T23257-2009 buried steel pipeline polyethylene coating technology standards3) Single PE anti-corrosion steel:
single layer PE is the use of anti-corrosion steel curtain coating process( also known as curtain method), the steel pipe after rotation frequency heating, steel top is fitted with a polyethylene powder container by pouring dusted steel tube surface polyethylene coating.
4) 3PE anticorrosive and external single PE anticorrosive performance comparison
11. Coal tar epoxy
The product is formulated with an epoxy resin, coal tar pitch, anti-rust pigments, additives, modified amine from. Products with rapid drying, good adhesion, flexibility, and easy two-component packaging and construction. With acid, alkali, salt, water, oil etc.;
2) Characteristics and Uses:
①The paint combination of high mechanical strength epoxy resin adhesive force, erosion and chemical resistance characteristics of asphalt water-resistant, anti-microbial, anti-plant roots, is a high performance anti-corrosion insulation coating, the products are Good chemical resistance, water resistance.
②suitable for oil, gas and water pipelines, water, gas, pipelines, refineries, chemical plants, sewage treatment plants and pipeline corrosion of equipment, may be used as antiseptic and mining offshore oil rigs and underwater portion of the ship , corrosion downhole equipment.
3) Coat corrosion:
High-density polyethylene jacket anticorrosive structure: the outer surface of the pipe wrapped high density polyethylene material with high mechanical strength and excellent corrosion resistance, can protect the pipe to avoid the transportation, installation and use of the process due to external factors damage caused. Manufacturing outer casing should be added antioxidants, UV stabilizers, and carbon black. Polyethylene outer tube easy to aging, such as open storage and other objects appropriate to tarp covered dumps should be kept away from heat and ignition sources, made after anti-corrosion steel, prohibit exposure, quenched, or polyethylene outer tube easy to crack, the impact of product performance and service life.
4) The process has been the duty epoxy powder coating using electrostatic spraying. Since epoxy powder Jin Su troubled by adhesion, epoxy powder dip has not been able to promote. Current come with three coconut epoxy powder dip developed special phosphate solution, for the first time to overcome the adherence problem epoxy powder dip process, began to dip epoxy powder of this emerging technology.
5) corrosion standards:
FBE epoxy powder preservative execution SY/T0315-2005<steel pipeline single FBE topcoat technical specifications>
2PE / 3PE preservative execution GB/T23257-2009<buried steel pipeline polyethylene outer coating technology standards>
Anticorrosive surface rust criteria: the outer surface of steel pipe sand-blasting by GB / T8923-2008 requirements of Sa2 1/2 grade steel anchor profile of the surface of 40-100μm.
Anti-corrosion steel base material including spiral, straight seam pipe, seamless pipe, etc., are widely used in our long-distance water, petroleum, chemical, natural gas, heating, sewage treatment, water, bridges, steel, marine water piling pipeline engineering.
①improve the life of the steel pipe;
②combination of mechanical strength and plastic pipe corrosion resistance in one;
③outer coating of 2.5mm or more, scratch resistance, bump;
④inner wall of the friction coefficient is small, 0.0081-0.091, reduce energy consumption;
⑤the inner walls meet the national health standards;
⑥smooth wall is not easy scaling, self-cleaning function;
1. Spiral welded steel pipe specification
2. Pipe geometric tolerance
1. Spiral welded steel pipe production process
2. Anticorrosive coating production process