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Duplex stainless steel tee is a commonly used pipe components, usually through the pipe bulging to obtain, its principle is to rely on the material of the plastic tensile, under pressure to make smaller diameter tube along the radial outward expansion. Duplex stainless steel tee is a head and a small branch pipe, obviously, the size of the two big is competent, indirectly from a small size is manifold. In pure oxygen pipeline, usually have pressure, then the activity of oxygen. Special equipment of duplex stainless steel tee: at the top of the pipe on the device, the device includes a metal, transformer, commutator, support, etc.; Metal bar is heated, the use of jacks and metal bar ejection, outward wall material nature out of the formation of a reducing tee blank; Then a certain length corresponding specification section welding on the reducing tee blank of ejection forming, produce the final product. Processing method of duplex stainless steel tee adapted to different specifications of the pipes on the reducing tee pipe fittings processing; The special processing equipment, simple structure, low cost, manufacturing reducing tee pipe don’t need another injection molding machine and injection molds, can reduce the production cost of this kind of pipe fittings, improve production efficiency. Source: wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)

For conventional oil pipe welding, the quality is difficult to control, and it is difficult to achieve the required welding slag not allowed in the interior, however, more efficient and widely used welding backing is made by manual arc welding method to cover. In this way the welding operation is simple, the welding operation is simple, not easy to appear pores, slag, incomplete penetration and other welding defects, and because the line capacity is small, so heat affected zone is small, small deformation, cracking trend. Tungsten inert gas welding abbreviation TIG (tungsten inert gas welding) welding. The tungsten arc generated by the electrode and the workpiece substrate and the hot-melt filler wire (filler wire, if used) is a welding method under the protection of an inert gas. Continuous welding of shielding gas from the torch nozzle, the arc formed around the protective layer and air gas isolation, to prevent the weld around the tungsten heat affected zone have a very harmful effect, allowing high-quality welding. The welding technology of oil pipeline: TIG welding advantages: 1) TIG welding can weld metals, etc., argon welding area can be effectively isolated from the surrounding air, it will not dissolve the metal, and metal does not respond. TIG welding process, arc welding and automatic removal of surface oxide film. Therefore, the success of other welding methods easy to oxidize easy welding, nitriding, chemical reactivity, nonferrous metals, stainless steel and various alloys. 2) the protection effect, the welding quality is high. Ar is one of the most stable and inert gases, it does not react with the metal reaction, soluble in liquid metal does not produce pores, and therefore has excellent protection properties. The welding process is basically a simple metal melting and crystallization process, so the welding quality is high. 3) As the argon gas flow to the arc compression and cooling, welding stress and deformation is small, the arc heat concentrated and high temperature argon, can ensure that the weld root penetration, heat affected zone joints small, welding distortion and cracking tendency. Particularly suitable for large-scale welding of steel air quenching tendencies. 4) tungsten arc stability, even in small welding current (<10A) is still under stable combustion, especially for thin, thin plate welding materials. 5) The heating and filling wires can be controlled, so easy to adjust the heat input can be welded in various locations, but also to achieve the ideal way to spray side welding. 6) Since the filler wire does not pass through the arc, no splashing or welding appearance is generated. 7) Ar is a single atomic gas, heat capacity is small, thermal efficiency is low, heat consumption is large, the arc stable combustion is very favorable, even in low current conditions and arc length, arc stable, easy to operate, easy to control the welding quality difficult pipe welding position All position welding. TIG welding in recent years, because it is of good quality, easy to operate, it has become a power company in the boiler heating surface tube welding installation and maintenance of common methods. Under field maintenance conditions, the welding position is limited by space constraints. The most commonly used process methods are undercoating TIG welding SMAW covering the entire surface or using TIG welding.

The seven advantages of stamping elbow: The first, light weight, stamping elbow density of 0.89 0.91 g/cm, is only one over ten of the steel pipe. And because the light weight, can industry greatly reduce the transportation cost and installation of construction strength. The second, good corrosion resistance, stamping elbow with a few hydrogenation agent, resistant to various chemical media, excellent acid resistance, alkali resistance, corrosion resistance, will not rust, corrosion will not, will not breed bacteria, no electrochemical corrosion. Third, good heat preservation, as a result of the stamping elbow materials, low thermal conductivity, the thermal conductivity of 20 degrees Celsius 0.21 0.24 W/mk, than steel pipe (43 to 52 W/mk), purple steel pipe (333 W/mk), so the pp-r pipe heat preservation is good. Fourth, heat-resisting performance is good: stamping elbow working temperature is 70 degrees, softening temperature is 140 degrees. Fifth, high impact, because the impact strength of the stamping elbow unique performance than other solid wall pipe have markedly improved, the ring stiffness is equivalent to 1.3 times that of the solid wall. Sixth, health, non-toxic: stamping elbow materials completely consists of two elements carbon, hydrogen, did not add any toxic heavy metal salt stabilizers, material of health has been through the national authoritative department detection performance. Seventh, long service life: stamping elbow under the rated temperature and pressure, the service life of up to 50 years, has the uv protection, radiation protection, make the product that never fade. Source: wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)

Boiler pipes often in high temperature and high pressure work, pipe smoke and water at high temperature steam oxidation and corrosion effects will occur, thus requiring durable steel with high strength, high oxidation resistance, and good organizational stability, high pressure boiler pipe in addition to chemical composition and mechanical properties, hydrostatic testing done by the root, to be flaring, flattening test. Steel to heat treatment delivery. In addition, the finished steel microstructure, grain size, there are certain requirements decarburization.  High-pressure boiler pipes are seamless steel pipe categories. Seamless same manufacturing method, but used in the manufacture of steel pipe, there are strict requirements. Often in high-pressure boiler pipes at high temperature and pressure conditions of use, the pipe under the effect of high temperature gas and water vapor, oxidation and corrosion will occur. Require durable steel with high strength, high resistance to oxidation corrosion, and have good organizational stability.  High-pressure boiler pipes are mainly used to manufacture high-pressure and high pressure boiler superheater pipes, reheater pipes, windpipe, the main steam pipe. High-pressure boiler pipes for low and medium pressure boiler (working pressure is generally not more than 5.88Mpa, working temperature below 450 ℃) of heating surface pipes; used for high-pressure boilers (above 9.8Mpa working pressure in general, the working temperature of 450 ℃ ~ 650 ℃ between) the heating surface pipes, economizer, superheater, reheater, petrochemical industrial pipe.

For the last 2 months , most of my suppliers have sent me emails informing that the prices of their raw materials have been increasing significantly (up 8%-19%）, so they have no alternative but to slightly increase their prices.If we look closely at the commodity market for the last 3 months of 2016 , China’s imports of commodities increased unexpectedly last month putting the world’s second-largest economy on track to set records for shipments of iron ore, coal and soybeans .In iron ore, the surge to one of the highest on record was partly due to the arrival of shipments delayed by the week-long Golden Week festival at the end of October. What is surprising is the buying has been strong even as steel pipe mills and copper fabricators prepared to slow output for weaker demand from the construction sector during the winter months. Why raw material prices are increasing in China in Q4 of 2016? On the demand Side The world economy is still recovering , The Chinese economy is slowing down and the Chinese winter ( known for low demand de commodities ) which usually lasts through February , may keep commodity supply weak The Chinese RMB had lost 10% of its value against the USD dollars during the last 14months , makes the import less attractive.Traditionally , the buying spree across commodities does not continue into December as consumers stock ahead of the holiday at the end of January the Chinese new year. On the Supply Side With demand picture and The surge of commodity imports , this is a possibility of inventory accumulation , which may put pressure on the prices to go down in the next coming months. The debate piding the market is whether this growth can be sustained into next year, or will be going back to the downside. There is no real reason for this rally in commodities .Therefore that leads many analysts to thinks that high prices are driven by speculation because they haven’t seen any real support from the demand side. The commodity prices in china were beaten up for last two years , and maybe some traders have seen a buying opportunity for short term gain.. Visit Steelhome.cn to stay up to date with the prices of raw material . The Chinese government is already stepping in to fight speculative trading in the commodity exchanges in Dalian , Zhengzhou and Shanghai by raising transaction charges. If the material price goes up by 15%, should the total product price also go up by 15%? Well ,It depends on the percentage of that material in the final cost in your product.It is important for buyers to understand the cost structure of their products to better negotiate any potential increase. If the metal consumption is the highest cost contributor, therefore a proportional increase makes sense.Yet, I have seen situations where the metal only contributes about 50% of the final product cost, but the supplier requested a proportional increase. which makes no sense. Conclusion: Chinese suppliers should expect some volatility in the market and in the cost of their production and buyers should anticipate to see the prices of their imported products from China to go up. BY Jamal Mernissi

Design and manufacture of a tap The internal thread on the stamping elbow usually adopts tap for tapping processing. Because stainless viscosity is higher, chip breaking performance is poor, so prone to chip in the process of tapping scratch artifacts thread or tap the phenomenon such as collapse edge, affect the efficiency and the quality of thread. In order to prolong the service life of tap, improve the quality of thread machining, the following points should be paid attention to. (1) to choose better tap material. Add special alloy elements, in ordinary high speed tool steel tap could obviously improve the abrasion resistance and toughness. (2) in tap thread surface coated with titanium nitride coating, can significantly improve the tap wear resistance, heat resistance and lubricity. (3) more appropriate tap backoff. But should pay attention to, such as large amount of backoff, prone to chip in the blade into the tap in the phenomenon of poor and tapping the thread finish. (4) choose reasonable tool heat treatment method, in order to give attention to both tap of hardness and toughness. (5) more appropriate Angle before the tap. But should pay attention to, such as tap rake Angle is too large, when the blade cause tap collapse edge and tapping the thread edges. Second, the selection of tapping oil Tapping processing for the stainless steel stamping elbow, the selection of tapping oil is very important. Tapping oil must have good cooling and lubrication and rust prevention function. Such as tapping oil cooling effect is not good, then tap easy sticky, namely before the tap threads and Angle of surface bonding stainless steel scraps. Such as tapping oil lubrication effect is bad, is poor, tapping the thread finish and tap tapping resistance is big. Stainless steel special tapping oil effect is good, can use directly. In addition, also can use tapping oil essence oil and configure, but matching to the right. Source: wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)

The best way to improve the quality of stainless steel pipe fittings is by ingot into a casting process. Due to the improvement of the continuous casting process quality control methods, this method has become a necessary means to improve the quality of products. Stainless steel continuous casting billet quality advantages embodied in the surface outside in addition to the first paragraph billet grinding rate has reached more than 70%, the overall appearance grinding yield reached 99.15% in order to achieve this goal must to refining of molten steel, low oxygen and sulfur content, do well the bag and tundish metallurgy, precise control of molten steel temperature, pouring without oxidation, further reduce the inclusion content. Continuous casting slab process for stainless steel pipe fittings are as follows: 1. According to different types of steel mould vibration process match the protecting slag, it can improve the yield of 10%, saving energy and shortening production cycle and improve the yield of liquid steel. 2. Stainless steel pipe fittings to adopt continuous casting, thus improve the comprehensive yield, but also to match the refining outside the furnace, improve the production efficiency, also omitted the breakdown process, saving a large amount of energy consumption. 3. Stainless steel pipe fittings for continuous casting is general with refining furnace, the chemical composition and temperature of molten steel is strictly requirements; In order to prevent the molten steel secondary oxidation, continuous casting production process requirements take no oxidation protective casting; Of ladle, tundish, sliding nozzle and submerged nozzle refractory material requirements strictly. 4. To ensure the appearance quality of casting billet, choose the appropriate maintenance slag; In the process of continuous casting due to the vibration of the mold in continuous casting billet is formed on the surface of the vibration mark to be controlled; Ferritic stainless steel pipe fittings must adopt electromagnetic stirring continuous casting. 5. After blowing argon station of molten steel temperature in the bag after fine-tuning rotary table waiting for continuous casting. 6. After the molten steel casting, stainless steel pipe fittings of vertical, generally USES the same as the carbon steel bending type or curved continuous caster. After refining of molten steel into the ladle, through rotary table will be pouring ladle to tundish sprue above, and then by water to molten steel into the tundish. Tundish ladle through submerged nozzle into the mold forming and condensation and down continuously. Solidification of the slab surface after secondary cooling period continue rapid cooling to billet length after heart into solid flame cutting, to the whole stainless steel pipe fittings casting billet process is completed. Source: wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)

October 19, 2016, Baton Rouge, LA — Today the CSB released its final report (Final Report October 19, 2016: PDF file) into the June 13, 2013, explosion and fire at the Williams Olefins Plant in Geismar, Louisiana, which killed two employees. The report concludes that process safety management program deficiencies at the Williams Geismar facility during the 12 years leading to the incident allowed a type of heat exchanger called a “reboiler” to be unprotected from overpressure, and ultimately rupture, causing the explosion. The Williams Geismar facility produces ethylene and propylene for the petrochemical industry and employs approximately 110 people. At the time of the incident, approximately 800 contractors worked at the plant on an expansion project aimed at increasing the production of ethylene. The incident occurred during non-routine operational activities that introduced heat to the reboiler, which was offline and isolated from its pressure relief device. The heat increased the temperature of a liquid propane mixture confined within the reboiler, resulting in a dramatic pressure rise within the vessel. The reboiler shell catastrophically ruptured, causing a boiling liquid expanding vapor explosion (BLEVE) and fire, which killed two workers; 167 others reported injuries, the majority of which were contractors. The CSB investigation revealed a poor process safety culture at the Williams Geismar facility, resulting in anumber of process safety management program weaknesses. These include deficiencies in implementing Management of Change (MOC), Pre-Startup Safety Review (PSSR), Process Hazard Analysis (PHA) programs, and procedure programs causal to the incident: Failure to appropriately manage or effectively review two significant changes that introduced new hazards involving the reboiler that ruptured—(1) the installation of block valves that could isolate the reboiler from its protective pressure relief device and (2) the administrative controls Williams relied on to control the position (open or closed) of these block valves. Failure to effectively complete a key hazard analysis recommendation intended to protect the reboiler that ultimately ruptured. Failure to perform a hazard analysis and develop a procedure for the operations activities conducted on the day of the incident that could have addressed overpressure protection. CSB Chairperson Vanessa Allen Sutherland said, “The tragic accident at Williams was preventable and therefore unacceptable. This report provides important safety lessons that we urge other companies to review and incorporate within their own facilities.” The CSB case study on the accident at Williams notes the importance of: Using a risk-reduction strategy known as the “hierarchy of controls” to effectively evaluate and select safeguards to control process hazards.  This strategy could have resulted in Williams choosing to install a pressure relief valve on the reboiler that ultimately ruptured instead of relying on a locked open block valve to provide an open path to pressure relief, which is less reliable due to the possibility of human implementation errors; Establishing a strong organizational process safety culture.  A weak process safety culture contributed to the performance and approval of a delayed MOC that did not identify a major overpressure hazard and an incomplete PSSR; Developing robust process safety management programs, which could have helped to ensure PHA action items were implemented effectively; and Ensuring continual vigilance in implementing process safety management programs to prevent major process safety incidents. Following the incident, Williams implemented improvements in managing process safety at the Geismar facility. These include, among others, redesigning the reboilers to prevent isolation from their pressure relief valves, improving its management of change process to be more collaborative, and updating its process hazard analysis procedure. Investigator Lauren Grim said, “Williams made positive safety management changes at the Geismar facility following the accident, but more should be done to improve process safety and strengthen the plant’s process safety culture. Our report details important safety recommendations to protect workers at the Williams Geismar facility.” To prevent future incidents and further improve process safety at the Geismar plant, the CSB recommended that Williams strengthen existing safety management systems and adopt additional safety programs. These strategies include conducting safety culture assessments, developing a robust safety indicators tracking program, and conducting detailed process safety program assessments. The CSB also identified gaps in a key industry standard by the American Petroleum Institute (API) and issued recommendations to API to strengthen its “Pressure-relieving and Depressuring Systems” requirements to help prevent future similar incidents industry-wide. Chairperson Sutherland said, “Most of the accidents the CSB investigates could have been prevented had process safety culture been a top priority at the facility where the incident occurred. These changes must be encouraged from the top with managers implementing effective process safety management programs.” The CSB is an independent, non-regulatory federal agency charged with investigating serious chemical accidents. The agency’s board members are appointed by the president and confirmed by the Senate. CSB investigations look into all aspects of chemical accidents, including physical causes such as equipment failure as well as inadequacies in regulations, industry standards, and safety management systems. The Board does not issue citations or fines but does make safety recommendations to plants, industry organizations, labor groups, and regulatory agencies such as OSHA and EPA. Visit our website, www.csb.gov.  For more information, contact Communications Manager Hillary Cohen, cell 202-446-8094 or email public@csb.gov. Source: U.S. Chemical Safety Board

Flat welding flange is a kind of disc parts, the most common in the pipeline engineering, flanges are used in pairs. In pipeline engineering, the flange is mainly used for pipe connection. In need of connecting pipes and all kinds of installation of a flange, the low pressure pipe flange can use silk, the use of more than 4 kg pressure welding flanges. By sealing point between two slices of butt weld flange, bolt. And then have different thickness and different stress of flange use different plug. Flat welding flange not only saves space, reduce weight, more important is to ensure that the joint parts will not leak, has good sealing performance. Compact flange size is reduced, was due to the decrease of the diameter of the seal, it will reduce the sealing surface of cross section. Second, the flange gasket has been replaced by sealing ring, to ensure that the sealing face sealing surface matching. Thus, in order to close cover only need a small pressure. As the pressure required to reduce, the size of the bolt and the required quantity can be reduced accordingly, so the final design out a small volume and light weight (70% ~ 80% reduction in weight than traditional flange) of new products. So flat welding flange flange products, a more excellent quality and reduce the space, has played an important role in industrial applications. Flat welding flange of main design drawback is that it does not guarantee no leakage. This is its design: the deficiency of the connection is dynamic, and such as thermal expansion and the ups and downs of cyclic load can create the flange surface between the moving, affect the function of the flange, to destroy the integrity of the flange is damaged, eventually lead to leakage. Any product may not have the flaw, not just the lack of control products to a minimum as far as possible, so the company in the production of flat welding flange to improve the performance of the product as far as possible, make it play a biggest role. Source: wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)

Hot rolled steel Hot-rolled is with continuous casting slab or blooming slab as raw material, after reheating furnace heating, high pressure water descaling into roughing mill, roughing material by the cutting head, tail, and then enter the finishing mill, the implementation of a computer-controlled rolling made the final rolling after coiling after the laminar cooling (computer-controlled cooling rate) and the coiler, straight hair volume. Straight hair the volume of the head, the tail is often poor, was a tongue-and fishtail, thickness, width, precision the edge often there is a wave-shaped, folding, pyramid defects. Coil weight heavier coil diameter of 760mm. (Normal pipe industry prefer to use.) Straight hair volume by the cutting head, tail cutting, trimming, and multi-pass straightening flat finishing line treatment, a cutting board or heavy volume, that is, to become: hot-rolled steel plate, flat hot-rolled steel coils, slitting with other products. Serve hot finishing volume descaled, pickled and oiled hot-rolled pickled coils. Cold formed steel Cold formed is as raw material, after oxide removal by pickling tandem cold formed finished rolling hard roll, work hardening due to the volume of the rolling hard due to the continuous cold deformation strength, hardness rise, tough Plastic indicators declined, stamping performance will deteriorate, and can only be used for simple deformation of the parts. Rolling hard roll can be used as the raw material of the hot-dip galvanizing plant, hot dip galvanizing line set annealing line. Rolling hard roll weight is generally 6 to 13.5 tons, the coil diameter of 610mm. The general cold strip mills, volume should go through continuous annealing (CAPL unit) to eliminate cold hardening and rolling stress, or batch annealing reach the mechanical properties of the corresponding standard specifies. The cold-formed steel sheet surface quality, appearance, dimensional accuracy superior to the hot-rolled sheet, and right rolling thin product thickness to about 0.18mm.  Difference between hot rolled and cold formed steel: 1, cold formed steel to allow cross-section a local buckling, which can make full use of the rod buckling bearing capacity;-section hot rolled steel does not allow local buckling occurs. 2, the residual stress of the hot rolled steel and cold-formed steel produced by different reasons, so the distribution of the cross section is also very different. The residual stress distribution in the cross section of cold-formed steel bending, residual stress distribution in the hot rolling steel or welded steel cross-section is a film type. 3 free torsional stiffness of hot rolled steel, cold-formed steel, the torsional properties of hot-rolled steel is better than cold-formed steel.

How to get rid of surface stains of cracking tube follow the steps below: The first step is to clean, we must first petroleum cracking tube surface oil, dirt, grease, and some other substances removed.  The second step is naturally acid, generally speaking, there are two pickling treatment, a chemical treatment, another treatment method is electrolysis, which can be handled in two ways petroleum cracking tube surface cleaning clean, but chemical pickling is a pipeline anti-corrosion measures.  The third step is necessary to use the tool to the surface of the oil cracking pipe polished, although the effect may not be very good polish, but this procedure is also indispensable. The final step is to make the surface of petroleum cracking tube jet, one can remove some of the dirt, the second is to make the roughness of petroleum cracking tube more evenly.  For petroleum cracking tube defects formed on the surface there are many, but certainly there are a lot of different reasons, the specific form of the crack is different, often found defective for its appearance on petroleum cracking tube we can see, the main reason for its main form by the following points. In fact, for the production process, the emergence of various drying phenomena of its raw materials for steelmaking summer rainy season or when it will produce up to steel gas content’s sake. In the process, the ingot when heated due to heating of the air bubbles are burned through, it will have more cracks after the rolling, which will meet the petroleum cracking tube relatively thin, dense and sizes, its length ranging from cracks, these things collectively referred to as hairline, this is a defect. So the cause of the surface oil cracking tube defects are many, so we have to remedy. After oil cracking pipe handling, appearance becomes smoother, more beautiful. Although after the rust will not affect the use again, but if we do the work in advance, so do not bother it. We buy petroleum cracking tube among the first to note that it is not a strong corrosion resistance, have a longer life does not have to select a high-quality petroleum cracking pipe products that can reduce our future work a lot of trouble.

The chemical compositions for some commonly used martensitic, precipitation hardening stainless steels are provided in the following tables. When specifying stainless steel chemistry, it is important to reference the appropriate ASTM standard and the UNS  (Unified Numbering System) number associated with the specific  alloy or grade.  UNS numbers are internationally recognized specific chemistry requirements.  If common names such as AISI numbers are referenced, the UNS number should also be used to avoid confusion. These compositions exclude phosphorus (P), sulfur (S), and silicon (Si).  Chemical composition requirements may vary with the specific product requirements so please refer to the appropriate specification. Table 1: Common Martensitic Stainless Steel Chemical Compositions (Weight Percent)Martensitic Stainless Steels Common Name UNS No. C Cr Ni Mo N Mn Cu Other 410 S41000 0.08-0.15 11.5-13.5 0.75 – – 1.00 – – 420 S42000 0.15 min. 12.0-14.0 0.75 0.50 – 1.00 – – 440A S44002 0.60-0.75 16.0-18.0 – 0.75 – 1.00 – – 440C S44004 0.95-1.20 16.0-18.0 – 0.75 – 1.00 – – Table 2: Common Precipitation Hardening Stainless Steel Chemical Compositions (Weight Percent)Precipitation Hardening Stainless Steels Common Name UNS No. C Cr Ni Mo N Mn Cu Other XM-13 S13800 0.05 12.3-13.2 7.5-8.5 2.00-2.50 0.01 0.20 – Al 0.90-1.35 XM-12 S15500 0.07 14.0-15.5 3.5-5.5 – – 1.00 2.5-4.5 Cb+Ta 0.15-0.45 632 S15700 0.09 14.0-16.0 6.5-7.7 2.00-3.00 – 1.00 – Al 0.75-1.50 630 S17400 0.07 15.0-17.5 3.0-5.0 – – 1.00 3.0-5.0 Cb+Ta 0.15-0.45 631 S17700 0.09 16.0-18.0 6.5-7.7 – – 1.00 – Al 0.75-1.50 Notes for All Tables: Date was extracted from ASTM specifications for plate, sheet, and strip when available or from company data sheets.  Chemistries are the maximum percentage, unless range or minimum is indicated.