SSAW Pipe

　　Hydrostatic pressure test is an indispensable part in the manufacturing process of steel pipe. Its function is to detect the anti-leakage function of steel pipe under the standard test pressure and steady voltage. It is the same as the flaw detection process of ray and ultrasonic, and is an important means to check the overall quality of steel pipes. So what are the regulations for the hydrostatic test of the casing pipe? The following is simple for everyone: 　　1. The hydrostatic test pressure value of the coupling and threaded pipe is the lowest value of the hydrostatic test pressure of the flat end pipe, the maximum hydrostatic pressure test pressure of the coupling, and the internal pressure leakage resistance, but the maximum pressure is 69 MPa, and 　　the calculation pressure is The value is usually rounded to the nearest 0.5 MPa. 　　2. According to the API requirements, the hydrostatic pressure test pressure measuring device should be calibrated within 4 months before each ...

　　Steel Pipe cleaning and maintenance need to follow certain methods to clean up. The main use of tools such as wire brush the surface of polished steel. Steel pipe cleaning and removal of loose or tilt can preheat the oxidation, rust, welding slag. Hand tools rust can reach Sa2 grade power tools rust up Sa3 level. If attached to a solid steel surface oxide scale, the result is not ideal tools rust, corrosion construction requirements not reach the depth of the anchor pattern. 　　Acid using solvent, emulsion cleaning fluid low pressure welded steel pipe surface, in order to achieve the removal of oil, grease, dust, lubricants and similar organisms, but it can not remove the steel surface rust, oxide, welding medicines, and therefore the production of anti-corrosion only as an adjunct. Different forms of ways and means to clear rust will cause some of the important impact of seamless, affecting a large number of performance and factors, in strict accordance with traditional Chinese me...

　　API early in 1926 released by the American Petroleum Institute (API) API-5L standard, initially including three steel grade A25, A, B, and later released several times. Prior to 2000, the worldwide use X70, about 40%, X65, X60 are in the 30%, a considerable number of small-caliber product oil pipeline selection of X52 steel grade, mostly for resistance welding straight pipe ( ERW steel pipe ). 　　China is currently used in the Petroleum Pipeline tube spiral welded pipe (SSAW), LSAW pipe (LSAW), electric resistance welded pipe (ERW). Diameter less than 152mm selection of seamless steel tubes. Of the late 1960s to the 1970s, spiral pipe plant rapid development of crude oil pipelines almost all spiral welded steel pipe, "West-East pipeline region selection spiral welded steel pipe. The spiral welded steel pipe of the disadvantage is the internal stress is large, the dimensional accuracy is poor, the probability of generation of defects. According to expert analysis, should adopt t...

　　Inner coating can greatly improve pipeline capacity. It can prevent corrosion and reduce the role of the pumping costs. Improving gas flow within the coating technology development update has become the main methods of transport in major companies to increase the amount. It can significantly reduce the friction between the gas and the tube wall which is the basic function of the inner coating technology. The friction caused by the tube at the factory of its inner surface is rough, the use of the inner pipe wall coating becomes smooth, the friction between the gas and the wall becomes small. It will accelerate the gas flow rate, and the cost of pumping the respective compression lower. 　　The coating into a file (dry film thickness of 80 ~130 um) coated on the inner wall of the tube. Epoxy resins are currently the most widely used in the coating material, a lot of in-service pipeline are in use. The inner coating should have a certain adhesion, porosity, elasticity, chemical resistan...

　　Welding neck flange is a type of pipe fittings which has “round neck” in the center. The “round neck” is already bevelled which is directly for welding with the pipe ends. The outside diameter of the “round neck” is the same as the connected pipe outside diameter. In general, the outside diameter for the “round neck” hole is ranges from 50mm to 2130mm. Around the “round neck” there are 4 to 48 bore hole which is used with bolts to connect two flanges together. The outside diameter for the bore hold ranges from 11mm to 30mm. The outside diameter for welding neck flange ranges from 75mm to 2190mm, and the thickness is from 12mm to 58mm. There are five types of sealing face for welding neck flange which are RF, MFM, TG, FF, RJ. 　　Welding neck flange has good sealing and distortion properties with a relatively cheap price. It is widely applied for pressure or temperature fluctuation pipeline under the nominal pressure less than PN 2.5 MPa, and also used for transporting expansive, fla...

　　Specified in ISO 4200, EN10220 or DIN2448, the specified size of steel pipe refers to the length, outside diameter, inside diameter and wall thickness of the steel pipe . The range size of steel is an effective measure to save materials. Today we will discuss the length of steel pipe. Delivery length is also known as customer required length or contract length. Steel pipe manufacturers or suppliers can supply according to standard length. The legal units of measurement for the length of steel pipe are “m”, ” cm” and “mm”. 　　Random length 　　Indefinite length refers to the length of steel pipe in the standard range and does not require fixed length, also known as the usual length. The steel pipes delivered by indefinite scale shall be delivered within the specified length range. For example, the standard of structural pipes stipulates: the length of hot-rolled (extruded and expanded) steel pipes is 3000mm ~ 12000mm; Cold drawn (rolled) steel tubes with a length of 2000mm ~ 10500mm ...

　　Hydrostatic pressure test is an indispensable part in the manufacturing process of steel pipe. Its function is to detect the anti-leakage function of steel pipe under the standard test pressure and steady voltage. It is the same as the flaw detection process of ray and ultrasonic, and is an important means to check the overall quality of steel pipes. So what are the regulations for the hydrostatic test of the oil casing? The following is simple for everyone: 　　1. The hydrostatic test pressure value of the coupling and threaded pipe is the lowest value of the hydrostatic test pressure of the flat end pipe, the maximum hydrostatic pressure test pressure of the coupling, and the internal pressure leakage resistance, but the maximum pressure is 69 MPa, and the calculation pressure is the value is usually rounded to the nearest 0.5 MPa. 　　2. According to the API requirements, the hydrostatic pressure test pressure measuring device should be calibrated within 4 months before each appli...

　　Size deviation mainly in the SSAW steel pipe is straightness, roundness, aspects of uneven thickness. 　　In most cases, straightness tolerance for the use of spiral steel pipe under large, but the manufacturing standards for spiral pipe straightness requests, if the predetermined value is exceeded, would constitute a reason to return, and therefore, spiral pipe plant should still be noted. Roundness tolerance will affect the use of spiral steel pipe, mainly in the group of the wrong side of the welding head. Roundness tolerance has led to the wrong side of the welded joint will not only reduce the pressure capability, but also stress concentration. When the site Group, roundness some pipe can be corrected. Outside diameter deviation and the impact on the spiral steel pipe used roundness tolerance fairly. 　　Non-uniform wall thickness generally easy to be ignored, and many spiral steel pipe standards are not clearly defined. If the wall thickness Uneven, it will not only result set...

　　Schedule pipe is the denomination given to the result rounded to the ten calculated by the formula: SCH = P / S where P is the working pressure of the pipe and S is the tension (pressure) corresponding to 60% of the material flow limit at 20 degrees. W. 　　Therefore for the same outside diameter of a conduit pipe, the larger the SCH the greater the wall thickness in relation to its diameter. The Schedule therefore defines the wall thickness of the pipe, and the values set for each Schedule (thickness) in the various diameters are tabulated and agreed in the corresponding standards. 　　For example, ASTM and NBR 5590 standards follow dimensions according to the standard defined in ANSI B 36.10. In less common standards, European DIN, BS and others, as well as Brazilian standards ABNT, is not common the designation of thicknesses in Schedule but rather as recommendation of ISSO (INTERNATIONAL STANDARDZATION ORGANIZATION) that establishes thickness classes, which are defined as table o...

　　Learn a little more about the galvanizing process in the manufacture of Galvanized Carbon Steel Pipes . 　　Research shows that corrosion is primarily responsible for iron loss in the world. Among the protection processes already developed, one of the oldest and most successful is hot dip galvanizing, or as it is better known, hot dip galvanizing. 　　It is a chemical process that coats steel with zinc. Thus, the main purpose of fire galvanization is to prevent the contact of the base material, steel (Carbon Iron alloy), with the corrosive medium. 　　Since zinc is more anodic than the iron element in the galvanic series, it is the one that corrodes, giving rise to cathodic protection, that is, zinc sacrifices itself to protect iron. 　　Hot dip galvanizing can be found in almost every type of application and industry where steel is employed. 　　Household industries, chemical processes, pulp and paper, construction, automotive and transportation, to name a few, have made great histo...

　　During the high frequency welding process, the welding technology, quality control process parameters, the impedance of the induction coil and the position of the placement has significant influence on the ERW steel pipe quality. 　　1. Control the steel pipe weld gap 　　If the weld gap is too much, it might increase the possibility of weld seam cracks. If the weld gas is too small, it will cause weld burning, molten metal splashes due to the excessive heat. It will affecting the quality of welding seam in the end. 　　2. The position of the high frequency induction loop 　　Induction loop should be placed in the same center line with the steel pipe. The distance between induction loop and the squeeeze roll end should be controled close enough without burning squeeze rollers premise. If the induction loop from the squeeze roll farther, the effective heating time will be longer and the heat affected zone will be wider. This will cause the strength of the steel pipe weld penetration ...

　　Residual magnetism causes and impact on quality of welding 　　When the gas pipeline construction and repair welding operations, sometimes magnetic blow phenomena affect the welding process. Forming a magnetic blow is the result of the presence of residual magnetism in the pipe metal. Typically, the magnetic induction and magnetic remanence divided into two processes. Magnetic induction in plants often produce tube links, such as: metal smelting, using electromagnetic crane for loading and unloading, pipe parked or garaged in a strong magnetic field, the magnetization is completed nondestructive inspection method, the pipe is placed close to power lines and so strong. Processes often produce magnetic welding operations during the assembly and the use of a magnetic holder, fixture and took DC welding pipes, such as: prolonged contact is connected to a DC power supply electric wire, bare wire segment or short-circuit pipe welding clamp and so on. 　　When welding with magnetic steel, o...

　　Internal thread is a common defect in the cross-rolling mill, and the form is full-length and local. The internal thread defect is the trace left by the deformation of the seamless steel pipe every half turn. When a fixed mandrel and a semi-floating mandrel are used, sometimes the internal thread defect is caused by the wear of the mandrel. The internal thread defects of the cross-rolling mill are just as difficult to avoid as the straight defects in the automatic rolling mill. It is important to minimize them. The reason for the formation of internal thread of seamless steel pipe is generally considered to be analyzed from the following aspects: 　　1) Surface state of the mandrel, such as mandrel wear, deformation, adhesion metal and scale. Because the mandrel participates in the deformation, the defects on the surface of the mandrel are necessarily reflected on the inner wall of the seamless steel pipe, especially the use of the fixed mandrel and the semi-floating mandrel; 　　2)...

　　Spiral steel pipe is also called a spiral steel pipe, which is generally referred to as a spiral steel pipe with a diameter of more than 1 meter. Steel pipes are subject to water pressure, tortuosity and pressure. Flat and other experiments have certain requirements on the surface quality. The general delivery length is 12 meters, often requiring fixed delivery. A metal material with a yielding phenomenon, the stress of the sample is not added (persistently stable) during the stretching process, and the stress at the time of elongation is continued, which is called the yield point. 　　If the force attack declines, the upper and lower yield points should be distinguished. The unit of the yield point is N/mm2 (MPa). The sample is connected during the stretching process. The maximum force (Fb), the stress (σ) obtained from the original cross-sectional area (So) of the sample, is called the tensile strength (σb), and the unit is N/mm2 (MPa). It shows the maximum ability of metal materia...

　　This type of auxiliary accessories within fluid control systems perform various functions such as directing fluids (elbows), pressure change (reductions), shunt (tees), flanged coupling (stub ends), are joined by butt welding , for which they have the characteristic of having a bevel, through it, the welding achieves a good penetration and mechanical resistance. 　　Butt weldable connections are manufactured under the guidelines of the ASTM standard (American Society for Testing and Materials) and of which we can find them with designation of grade WP and CR. 　　In the connections WP grade (Wrought Products), products of conformation of its translation into Spanish, its dimensions are governed by the standard ASME (American Society of Mechanical Engineers) B16.9 to be used in high pressure and temperature systems. 　　While the CR grade (Corrosion resistant) connections, have the dimensions of the guidelines of the MSS-SP43 (Standardization Society for Valve and Connection Manufactu...