Thursday, November 27, 2014

What benifit from the Silk Road economic belt construction

Recently, the Environmental Impact Assessment of West-East Gas Pipeline Project four lines gets into the second publicity. Earlier, China National Petroleum Pipeline West Company confirmed that the National Development and Reform Commission has issued Xinjiang Uygur Autonomous Region Development and Reform Commission a consent document of approving preparatory work of West-four line project to carry out. This shows that the West-four line project has entered a substantive stage of implementation.
Four-wire project has annual gas transmission capacity of 30 billion cubic meters, oil and gas pipeline steel demand will reach more than 100 million tons. According to the latest news of Xinjiang Exit Inspection and Quarantine, it is expected in early June, China-Central Asia gas pipeline C line can deliver imported natural gas to China West-C third line. C line started in 2011, designed gas transmission capacity of 25 billion cubic meters / year, project cost of $ 2.2 billion, completed by the end of 2013, the current project has been completed and acceptance. These show that the SSAW steel pipe market ushered in opportunities by the Silk Road economic belt construction.

Wednesday, November 26, 2014

Roll pass desigh of welded steel pipe

Hole is made by the tank formed by a pair (or more) rolls rolling. Steel strip deformation to a certain shape (rolled) through the hole, and through a series of successive deformation molded into a cylindrical tube. For the series of grooved shape and size selection, calculation and determination, and finally drawn into roll chart, the whole process is called the roll pass design. The basic requirements for roll pass design of welded steel pipe (LSAW and SSAW steel pipe)are:
(1) with a minimum passes (i.e., the shortest length of the deformation zone) to complete the forming and deformation process;
(2) the generated edge extending as small as possible when molding without creating ridges and folds;
(3) the edges are fully deformed and tube joints for no beak-shaped;
(4) stable strip forming in the hole;
(5) uniform deformation, roll small and uniform wear;
(6) low energy consumption;
(7) ensure the pipe dimensions and surface quality meet standard requirements;
(8) roll processing convenient, easy to manufacture, pass design can be combined with added processing;
(9) the pass design is with the characteristic of standardization, which can fit the unit with the same type of product specifications;
(10) can make use of computer-aided design (CAD).

DWTT of pipeline steel

DWTT (drop weight tear performance) is an important performance parameters of pipeline steel. Pipeline steel pipe includes seamless steel pipe and welded steel pipe (LSAW and SSAW steel pipe) and for the pipeline steel used for the production of oil pipeline, it not only requires a certain strength, but also a certain toughness, so the production pipeline are all required a DWTT test, and this parameter has a close relationship to its body ferrite.
For the impact of ferrite type on DWTT: pipeline generally form the inner polygonal ferrite or acicular ferrite.
The role of polygonal ferrite is:
1) coordination deformation. Due to the polygonal ferrite belongs to a low strength and good ductility phase, there is an appropriate amount of polygonal ferrite can improve coordination among various organizations deformation capacity, in addition, the presence of grain boundaries of pearlite also makes coordination ferrite deformation limited, the deformation resistance to increase, and expansion work successfully shaped crack increases, thereby improving toughness.
2) passivation crack tips. Polygonal ferrite belong to the toughness organization with low strength, it can make a greater plastic deformation in the crack tip, impeding crack propagation, meanwhile the crack tip stress gets relaxed and the crack tip passivated. In addition, a certain amount of polygonal ferrite grains will continue to force the crack go through the pearlite structure and polygonal ferrite, a large number of the interface suppresses the crack propagation, so that the toughness is improved.

long-distance slurry pipeline pipe

Particularity research with long-distance slurry pipeline pipe technology
The principle in the application of Long-distance slurry pipeline and oil and gas transmission pipelines is the same, but the delivery media is different, thus forming their own transportation technology. The main parameters of Kunming Dahongshan iron ore pipeline system has been put into production last year are as follows:
Transmission capacity 2.3 million t / a
Conveyor length 171Km
Pipe material API 5L GrX65
Pipe wall thickness 7.9 --- 14.7mm
Pipe diameter 244.5mm
Working pressure 24.4mpa / max
Pulp density of 65%
Transport velocity 1.5m / s
Concentrate fineness 80-0.043mm
According to its transmission medium and process, it puts forward specific technical requirements for the welded steel pipe, especially the technology selection of steel pipe.
In theory, the long-distance slurry pipeline selection can be a seamless steel pipe, high-frequency straight seam resistance welded steel pipe (ERW steel pipe), double-sided straight seam submerged arc welded steel pipe (LSAW steel pipe), but considering the economic pipeline investment and delivery amount break-even point, the length of the 100km pipeline is the most economical, ERW steel pipe and LSAW steel pipe are generally used. Information from the project abroad, pipe diameter minimum 114.3mm, wall thickness of 7.1-12.7mm, the largest pipe is 660mm and maximum wall thickness of 23.01mm, steel grade for x52-x70. Owners tend to choose ERW steel pipe, but ERW steel pipe limited to the wall thickness and grade, the majority uses LSAW steel pipe. From pipe technology, ERW steel pipe through the weld heat treatment process is better than the LSAW steel pipe with wide weld.

Tuesday, November 25, 2014

Why the ERW steel pipe aces in the city gas pipeline network construction

"Town Gas Design Code" provides the gas pipeline with pressure greater than 0.4Mpa. The pressure is less than 0.4Mpa pressure and low-pressure gas pipeline should use polyethylene pipe, mechanical interface ductile iron pipe, steel steel or steel skeleton plastic pipe. For pipeline for urban transport, the ERW steel pipe more than 0.4Mpa pressure is with undisputed status compared to other materials used in the steel pipe. Therefore, ERW steel pipe is the preferred city gas pipeline network construction.
1, In terms of the safety, for the city gas pipeline network main pipe, the bearing capacity, tensile strength and elongation of ERW steel pipe are all far greater than cast iron pipe, and bearing capacity, tensile strength and the ability to adapt to the temperature difference are far greater than "PE "pipe; and in terms of the interface rigors, ERW steel pipe weld interface is far much more closely than the cast iron pipe, and much more solid;
2, in terms of the adaptability, ERW steel pipe is suitable for gas, LNG, LPG, liquefied natural gas and air mixture, and cast iron pipe on the ability to adapt to LNG and natural gas is much less; ERW steel pipe capacity to adapt to temperature and pressure range is much greater than the "PE" pipe.
3, In terms of the economic aspect, ERW steel pipe is cheaper than ductile iron pipe. And when more than φ160, ERW steel pipe is also cheaper than the "PE" pipe (generally speaking, most of the city gas main pipe φ300 or so).
4, corrosion resistance of ERW steel pipe is not as good as cast iron pipe and "PE" pipe, which is an important issue to be sure to take a good anti-corrosion measures in the design and construction.

Monday, November 24, 2014

12Cr1MoV high alloy seamless steel pipe

              GB5310 standard 12Cr1MoV high alloy seamless steel pipe 
               bearing capacity parameters allowable stress lookup table
                            Chemical composition of high-pressure alloy steel pipe
  
  steel  
           Chemical composition%
       C
        Si
       Mn
      P
     S
       Cr
      Mo
         V
12Cr1MoV 
0.080.15
 0.170.37
 0.400.70
 ≤0.035
 ≤0.035
 0.901.20
 0.250.35
  0.150.30
                      
                         Mechanical properties of alloy seamless steel pipe

steel
WTmm)
 бb(Mpa)
 бs(Mpa)
 δ5(%)
  aku(J)


12Cr1MoV
   ≤16
470640
    ≥255
   ≥21
    ≥59



                          Alloy seamless steel pipe allowable stress
steel
WTmm)
Allowable stress (Mpa) under the following temperature (℃)
≤20
100
200
300
350
400
500
525
550
575
12Cr1MoV
≤16
147
144
126
110
104
98
89
82
57
35


Seamless steel pipe for low and medium pressure boiler

Pressure seamless steel pipe because of its special purpose, a series of tests must be made before using. If not, it is likely to leave hidden problem for future safety production. Because of the working pressure of low and medium pressure boiler seamless steel pipe is less than 5.88Mpa, operating temperature is below 450 ℃; this is a rough range, as long as the low and medium pressure boiler seamless steel pipe is produced according to the standards, there is no problem to use it normally. Of course, it has no problem also for the medium pressure boiler seamless steel pipe to be pressurized to about 7,8MPA, but if it is long-term work under this pressure, seamless steel amounted to less than its normal life. Leakage may occur and cause accidents in advance.
(1) flattening test
For outside diameter D> 22 mm, wall thickness S≤10 mm pipe, flattening test should be carried out, flat pitch h following formula
h = (1 + α) S / (α + S / D) where S --- pipe wall thickness, mm;
D --- pipe diameter, mm;
α --- unit length deformation coefficient, 0.08; when the S / D≥0.125 0.07.
(2) Bending test
D≤22mm outer diameter pipe bending test should be carried out. Bending angle is 90 °, the apex radius of 6 times the pipe diameter. Not bend cracks and cracks.
(3) hydraulic test
Should be carried out by the root test, the test pressure P (MPa) is calculated as follows, but 10 steel maximum pressure 7 MPa; 20 steel maximum pressure 10 MPa, the regulator for not less than 5 s.
P = 2SR / D where S --- nominal pipe wall thickness, mm;
D --- nominal diameter pipe, mm;
R --- allowable stress, provides 60% of the yield point, MPa.
Supplier eddy current testing can be used instead of hydraulic tests.

How to choose the way to weigh the steel pipe

The weight of the steel pipe is the most important parameter in the trade, which determines the steel trade fair and just. In general, there are two ways to weigh the steel pipe: the theoretical weight and weighing weight. Theoretical weight of steel is through the theoretical data (actual measured pipe outside diameter, wall thickness and length) and calculate the weight by a mathematical formula, the formula is: = weight per meter of pipe (OD - Wall Thickness) * wall thickness * 0.02466, the unit value is KG; weighing platform weight is hanging pounds or so on the actual weighed weighing tool steel weight. But in the steel industry, for different steel tend to have their own "hidden rules."

Whether seamless steel pipe, straight seam steel pipe or forged steel pipe, their theoretical weight formula is :(OD - wall thickness ) * wall thickness * 0.02466 = KG per meter of pipe. Generally speaking, this theoretical approach is a little less than the actual weight of the seamless steel pipe, is approximately equal to the actual weight of the forged steel pipe, but a little greater than the actual weight of lsaw steel pipe, ssaw steel pipe or erw steel pipe. In view of this, the seller will take a different approach to weight in the actual process. Straight seam steel pipe is generally taken as the theoretical weight mode, seamless generally uses the weighing weight way. For which way to choose, we can find the cause in the steel manufacturing process.

Longitudinal steel pipe is made with open flat plate or roll, and the actual thickness of the plate or a plate generally have a lower differential, about 0.25mm-0.5mm less than the theoretical thickness, so the weight of the theoretical weight way is to be greater than weighting way; while for the actual thickness of the seamless steel pipe is generally poor, the small thin-walled seamless steel pipe, seamless steel pipe, 20MM thick seamless steel pipe above it on the poor big, can reach 1-2MM, if 40MM or 50MM thick, seamless steel pipe, seamless steel pipe wall thickness can be the difference between some manufacturers to 3-5MM, and the next is almost no difference, so as to ensure that only weigh the seller does not lose tons. Same as for forging steel, because of its very high precision product processing, diameter and wall thickness fairly standard, so conducive to the theoretical formula worked out important and weighing weight.

Sunday, November 23, 2014

Related equipment performance capabilities of welded steel pipe

Longitudinal welded steel pipe depending on the welding process is generally divided into two types:. ERW steel pipe and LSAW steel pipe. According to different forming ways, LSAW steel pipe can be divided into: UOE steel pipe, JCOE welded pipe and HME steel pipe.
Related equipment performance capabilities overview.
1. Uncoiler: Board width 400-1250mm, removable inner diameter ¢ 610-760mm, outside diameter ¢ 1200-1800 (max 2000mm) mm, Material ≤X70 (standard APISpec5L)
2. pinch leveler: strip width 400-1250mm; strip thickness 4-14mm;
3. Shear welder: strip width 400-1250mm, strip thickness 4-14mm, material X70;
4. Horizontal Spiral Looper: feed circle diameter ¢ 12000mm, the out-material circle diameter ¢ 4600mm, the out-material on the circle strip helix angle 5.363 °, inlet velocity 40-180m / min, exit speed 8-25m / min;
5. fine leveler: strip width 430-1250mm, strip thickness 4-14mm, leveling roll diameter ¢ 180mm, roll length 1350mm.
6. Disc Cutting Machine: Cutter diameter ¢ 480mm, splicing pull scissors;
7. molding machine: pipe diameter ¢ 127- ¢ 381 (5 "-15") pipe wall thickness 4-14mm, pipe length 6-14m, high-frequency straight seam welded roll cold-formed connection (W shape)
8. welding unit: pipe diameter ¢ 127- ¢ 381mm, wall thickness of 4-14mm.
9. sizing unit: steel pipe diameter ¢ 127- ¢ 381mm, wall thickness of 4-14mm;
10. Roll cutting: cutting range ¢ 127- ¢ 381, the wall thickness of 4-14mm, cutting speed 30m / min.
11. The flat head chamfering machine: machining range ¢ 127- ¢ 381, the wall thickness of 4-14mm, processing capacity 2 / min
12. The hydrostatic pressure testing machine: Adaptation ¢ 127- ¢ 381, the maximum test pressure 25Mpa, processing speed 1.5 / min,
13. Online ultrasonic testing machine: Adaptation, diameter ¢ 127- ¢ 381, vertical linear greater than 3%, the linearity level of better than 1%, dynamic range ≥35dB, defect detection rate ≥95%, sensitivity margin than 35dB.
14. The off-line ultrasonic testing machine: Adaptation, diameter ¢ 127- ¢ 381, vertical linear greater than 3%, the linearity level of better than 1% , dynamic range ≥35dB, defect detection rate ≥95%, sensitivity margin than 35dB.,
15. IF Thermal Processor: Power 600KW2 units, heating temperature: 500 ℃ -1200 ℃, frequency 1KHZ-2KHZ, speed 6-25m / min, heating width ≥20mm, material X70, casing J55.
16. screen hydraulic universal testing machine: WEW-600C, using computer control, for metal bending tensile, compression (squash), shear test maximum load 600KW.
17. Charpy impact test test machine: JB-300B, the maximum impact energy 300J.

Friday, November 21, 2014

Requirement for marine engineering steel pipe materials

Requirement for marine engineering steel pipe material is essentially the requirement for the steel itself, there are low carbon steel, high strength steel, super high strength steel and stainless steel four categories. And in terms of the steel pipe, there are the following three aspects demand:

1. Conventional system steel pipe
For different ship and marine engineering, there are both conventional systems and proprietary systems. Ship life is generally 20 years. Conventional systems: bilge, ballast, sparse drainage, sewage, air, measuring, implantation, domestic water, fireproof, cargo, stripping, air, inert gas, heating, washing, foam fire extinguishing, watering, evaporation gas, liquid level sensing, remote control valves and other systems, special ships also include transportation of liquefied petroleum gas (LPG), liquefied natural gas (LNG) and other special systems. Marine engineering life is up to 30 years or even longer. In addition to conventional marine engineering systems, there are special drilling equipment systems, workflow systems Oil / LPG / LNG processing, special mooring system, flare systems, and so on. Therefore, the shipbuilding industry has become a big user of steel pipe market.

2. The structural steel pipe
Marine engineering steel pipe applications, in addition to the above conventional systems and proprietary systems, many construction uses a lot of steel pipes, such as jacket, underwater steel piles, watertight casing, mooring bracket, helicopter platform, torch tower and so on. Such steel pipe is with many specifications, high materials, and has the same diameter, different diameter and different wall thickness, as well as a large number of Y, K, T type of pipe nodes, such as jacket, steel piles, wellhead riser sets, mostly for large diameter steel pipe, and usually crafted with steel volumes. They are made of E36-Z35, D36-Z35, E36, D36. Standards for such steel pipe is no longer YB, CB, but mainly GB712-2000. Steel production is based on the Technical Committee of China's petroleum industry standards (CPSC) developed "structural steel manufacturing practice" SY / T10002-2000.

3. Special-purpose steel pipe
Special-purpose steel pipe means the special steel pipe under specific working environment and working media. Subsea pipeline is the typical special steel pipe, with larger demand, high strength, small tolerances, good corrosion resistance and other characteristics. At present, China's subsea pipeline production is still in its infancy because of welding materials, corrosion resistance or small size (diameter and wall thickness), expensive price and so on.
China's crude oil at sea need insulation delivery. In the past, double insulation structure pipe is safe and reliable, however, as protection tube it is not economical, and when do offshore pipe laying operations, inside and outside pipe welding shall be carried out at first, which greatly reduced pipe-laying efficiency, resulting in installation costs doubled. In the 21st century, people launched a concrete counterweight pipe. Its structure is (from inside to outside): steel, epoxy powder (FBE) coating, polyurethane insulation, polyethylene (PE) jacket pipe, reinforced concrete counterweight layer (internal configuration of steel wire). It is reported that, with this pipe, per kilometer subsea pipeline can reduce the cost of 0.5 million to 1 million yuan, greatly reducing the cost of offshore oilfield development, so that a number of marginal oil fields to be developed efficiently economically.

UOE steel pipe for deepwater pipelines

Pipes with UOE process shall go through the different horizontal and vertical stress cycle. These cycles combined will affect the performance of the piping materials under pressure. And pipe forming is determined in the production process, which can achieve the optimum balance between the parameters reproduced, the pipe compression and the pipe expansion. U and O-pressed combination ensures that the pipe size can be controlled to the highest precision. Improve the pipe roundness, the wall thickness and diameter tolerances can guarantee the designer the quality of the pipe, eliminate inaccuracies in the design and production and so that the wall thickness to achieve the optimum. 
Recently, Perdido Norte of the Mexico gulf is one of the world's deepest pipeline system, spent about 312 km of UOE line pipe, weighing about 77000 gt and used in the deep sea of 3500 to 8300 feet. One of the sections of the pipeline transport products from Alaminos Canyon 857 to the 994 area. Length of approximately 125.5 km.
In 2001, Bluestream project uses a 94 km, weighing about 45000 gt triple coating high quality polypropylene pipes and elbows. This project is technically very challenging. It is through the Black Sea to transport natural gas from Russia to Turkey. And UOE line pipe relying on its excellent resistance to stress makes it is used for the deepest section of the seabed at a depth of 2150 m. As early as 2000, Exxon Hoover / Diana project uses 64 km of UOE steel pipe, a depth of 1450 m. Deepwater pipe is with very small dimensional tolerances, in order to enhance the anti-static pressure capacity of the pipe and the annular weld fatigue resistance. In addition, 16-inch to 28-inch pipeline is seen as the future direction of deepwater pipeline. UOE technology to replace the use of Pilger seamless steel pipe can significantly reduce costs.

Thursday, November 20, 2014

Deepwater pipeline design:UOE or Seamless

The conventional pipe design is mainly considering of withstanding internal pressure. The greater the ability to withstand the pressure, the greater the flow of the tube, and thus the operators who will have greater efficiency. But for the design of deepwater pipelines, against external pressures become an important issue to consider, especially during the installation period. "Within the field" pipeline, such as subsea pipe, riser pipe and flow line pipe, because of the small diameter, it has a strong anti-hydrostatic capabilities. And for these, seamless steel pipe are generally used, which is easily obtained and is a more economical solution. However deepwater tieback lines and long-distance pipeline system generate a greater challenge for pipe design. In order to obtain a greater yield of the seabed, it tends to use a larger diameter and larger wall thickness tube to ensure that the pipeline can withstand the hydrostatic pressure and the need for bending. Pilger process can produce the desired thick-walled tube, but the manufacturing process is slow, the material cost is also high. The most economical method of manufacturing such a line is the UOE process. UOE process is pressing the steel plate into a U-shaped, then rolled into O-type, and then circumferential expansion. The improving requirements of the industry put forward limit challenge for the design of such pipelines. These requirements include the economy of safe and successful installation and the costs. Generally speaking, UOE steel pipe is more economical than seamless steel pipe.

Market opportunities of West-East Gas Pipeline Project line four

West-East Gas Pipeline Project four line is with a total investment of 34.62 billion yuan, starting from Yining, end with Zhongwei, way across Xinjiang, Gansu, Ningxia three provinces (autonomous regions), pipeline total length of 2,454 km. West-East four-line project is an important part of the national gas pipeline network, and the construction has important meanings of further improve the transmission ability of natural gas resources in Xinjiang to Middle east market, ease the tension between supply and demand contradiction of national gas and build and improve our energy strategy western channel .
The project is scheduled to start construction this year, and finished in 2017. According to stakeholders, the SSAW steel pipe pressure of the project is 12MPa, the diameter is 1219mm, estimating steel grade is X80, and wall thickness of 8.4mm. Construction of this project can not only promote the country's energy structure optimization and energy reduction discharge process, promoting coordinated regional development, but also can promote the equipment, materials and other related industries, thus pipe steel companies and enterprises will get many market opportunities.

Wednesday, November 19, 2014

Introduction of inner plastic steel pipe

Test items which should be carried out of the inner drag-reducing coatings mainly have production testing and laboratory testing two categories. Production testing refers to the pinholes testing, dry film thickness detection, bending testing, adhesion testing, cure test and immersion detection of the sampling during the coating process. Before manufacturing, the laboratory testing of the coatings quality should be preceded with the prepared spray specimen in the lab, and the projects are salt spray test, the immersion test, the peeling test, bending test, adhesion test, hardness test, the test pressure foaming , wear testing and pressure foaming test and so on.
The inner plastic steel pipe has excellent corrosion resistance, and its resistance to environmental stress cracking test is more than 1000h; good wear resistance coating; coating is smooth and not mixed with bacteria and fungi, has an effective anti-wax, scale effect, and with good health performance; water resistance coefficient is small, water capacity increased by more than 10% compared to the quantity of galvanized steel pipe. External galvanized steel pipe can both ensure the corrosion resistance in the atmosphere, and maintain the advantages of galvanized steel easy to buckling set, easy to install, bump-resistant, easy to transport, resistance to mechanical abrasion, and surface looking good. The outside galvanized and inside plastic coating steel pipe owns the internal and external advantages of coated steel pipe and galvanized steel pipe, can be used as petrochemical, water supply, electricity and other sectors of water, gas and other media transportation pipeline.

JCOE steel pipe performance in the world

JCOE steel pipe performance in the world
JCOE technology is the most important one of LSAW steel pipe technology development in the past ten years, its appearance greatly reduces the LSAW steel pipe production line investment, making the small and medium enterprises are also able to enter the LSAW steel pipe manufacturing threshold. And because of the small investment of JCOE unit and flexible production processes, its product quality is equal to UOE fairly, so it gets rapid development worldwide. At present, the number of JCOE units worldwide has more than 50 sets, China accounted for a quarter of it, which is far  exceeding the number of UOE units, and JCOE technology has become the mainstream technology of LSAW steel pipe production. Looking from forming principle, JCOE is more suitable for smaller or larger diameter, high grade steel pipe, such as the seabed steel pipe forming, and the large wall thickness bending tube forming.
In 2005, the India Welspun company adopted JCOE process and successfully produced  depth 2400m record of TTP pipeline pipe in Mexico seafloor, making JCOE steel pipe successful get into the market of subsea pipeline. The Russian OMK VYK-SA pipe company pass through the Nord Stream pipeline owners and DNV audit, won the Baltic seabed gas pipeline - 25% of the order of Nord Stream pipeline, 10 million tons & 1420mm JCOE products have entered the world's largest subsea pipeline. In the field of JCOE pipe, the German SMSMEER (former internationally renowned Mannesmann), Japan NKK Corporation, Japan OTK (Osaka Special Steel Plant), India WELSPVN pipe company, Hyundai Heavy Industries and the World Bank and Asian companies all have their unique innovative technology. China's petroleum systems and pipe colleagues in Taiwan on the technical equipment  has been in a leading position.

Tuesday, November 18, 2014

oil gas pipelines standards

Line pipe is divided into a variety of different kinds by the production process, but the main use of oil and gas pipelines are seamless steel pipe(SMLS steel pipe), high-frequency straight seam resistance welding pipe (HFW steel pipe), Longitudinally Submerged Arc welding steel pipe(LSAW steel pipe), and spiral submerged arc welded pipe (SSAW steel pipe).
And it mainly has four kinds of standards as below:
GB/T9711.1-1997 "The oil and natural gas industries - Steel pipe technical delivery conditions for the first Part: A grade steel", GB/T9711.2-1999 "The oil and natural gas industries - Steel pipe Technical delivery conditions for the second part: B Grade Steel", GB/T9711.3-2004 "The oil and gas industries - Steel pipe technical delivery conditions for the third part: C grade steel" (ISO3183-1996 / 1999), API SPEC 5L "specification for line Pipe".

Types of oil and gas pipe

Types of oil and gas pipe
1. Seamless steel pipe: diameter range of Ø6mm ~ Ø660mm, common specifications below Ø406mm, Ø406mm above specifications require heat flaring rolling. Seamless steel pipe common defects are too large wall thickness deviation, poor surface quality, scale, folding and so on.
2. LSAW steel pipe: diameter range of Ø406mm ~ Ø1625mm, the minimum wall thickness is generally 6mm, and the quality is relatively good. LSAW pipe forming quality is better than spiral submerged arc welded pipe, pipe weld length for SSAW pipes of the same length is larger than the LSAW pipe length.
3. SSAW steel pipe: diameter range of Ø273mm ~ Ø1625mm, maximum wall thickness is usually 20mm, due to the molding process, there is a large residual stress in the spiral submerged arc welded pipe, and its quality is relatively lower than LSAW steel pipe.
4. ERW steel pipe: diameter range of Ø152mm ~ Ø660mm, maximum wall thickness is generally not more than 19mm, its quality is relatively lower than LSAW steel pipe, common defects are weld groove-like cracks, excessive burning, pins type weld, gray spot and so on. Due to the size limitations of seamless steel pipe and ERW steel pipe, LSAW and SSAW are adopted when the tube diameter is relatively large.

Monday, November 17, 2014

Technical measures of the oil pipeline to prevent lightning hazard

Technical measures of the oil pipeline to prevent lightning hazard:
1. The oil pipeline itself is available for the receptor, and it shall set the metal jumper in the connection parts of flanges and valves. When the flange bolts with five or more connections, it can not be connected with metal wire, but must form an electrical pathway.
2. All metal parts of the piping system, including the metal cladding of the sheath, must be grounded. Line at both ends and every 200-300m, and the branch, the corner must have one of them grounded, grounding point should be located in the tube pier, and the impact grounding resistance must not be greater than 10Ω.
3. combustible gas vent pipe must be installed lightning rod, and lightning rod protecting area should not be less than 2m beyond the tube end, and horizontal distance no less than 3m  from the tube end.

Thursday, November 13, 2014

Import tax abolishment of Ukrainian steel pipe

According to the Ukrainian Trade Ministry spokesman, starting from November 1 the customs union abolished the import tax on seamless steel pipe to Ukraine, allowing the Ukrainian manufacturers quota-free export to Russia, Belarus and Kazakhstan. While the Customs Union used to impose special duties of Ukraine steel pipe, taxes of 9.9%, and in 2012 began to implement quotas on such goods.
Background: Russia began to implement tariff restrictions on Ukrainian steel pipe since 2010, and after October 1, 2011, this policy was extended to all Member States of the customs union, and changed to the Quota Management System since September 23, 2012. And in 2013, Ukrainian steel production fell 20 percent, from January to October 2014 compared with the same period last year, fell 15 percent, up to 23.415 million tons.

Wednesday, November 12, 2014

Why the LSAW units layout in the Yangtze River Delta region

LSAW unit dense layout in the Yangtze River Delta region for three reasons: 
First, the end of the second and third long-distance pipeline natural gas project is in the Yangtze River Delta region, meanwhile, the city gas pipeline network and marine pipelines develop very fast with a large market of line pipe. 
Second, LSAW steel pipe production is using heavy plates as raw materialsand Baosteel, Shagang, Nanjing and other heavy plate production enterprises are widely distributed in the Yangtze River Delta region. 
Third, the largest heavy plate reaches 5 meters wide, and it need waterway or sea to transport. The Yangtze River Delta region is bordering the East China Sea, creating favorable conditions for heavy plate transport. 
The big market, rich raw materials and convenient transport conditions creates the amazing conditions for LSAW unit building.

LSAW steel pipe units in China

China's LSAW steel pipe mill is showing the characteristics of overcapacity and centralized layout.
As the research statistic shows, there are total 25 sets of domestic LSAW steel pipe UOE / JCOE units, with a total production of 5.43 million tons. At present, there are two characteristics of China's LSAW steel pipe UOE / JCOE unit:
1. overcapacity. China's oil and gas pipeline market mainly includes three parts: one is the Oil and Gas Pipeline oil system, the annual demand of about 3 million tons; the second one is the export market, the annual demand of about 2 million tons; the third one is city gas pipelines and around the city's liaison with the mainline branch, the annual demand of about 3 million tons. Annual demand on the oil and gas pipeline home and abroad totaled 8,000,000 tons. But the production of large diameter spiral submerged arc welded pipe line pipe capacity of approximately 6 million tons, plus UOE / JCOE straight seam submerged arc welded pipe mill capacity (5.43 million tons) to reach a total of more than 1100 tons, thus, overcapacity of 300 million tons.
2. too dense layout in the Yangtze River Delta region. There are three sets of UOE / JCOE unit in Shanghai, respectively, Baoshan Iron & Steel Co., Ltd., Shanghai Tianbao Pipe Company and Shanghai monthly tide Pipe Company; there are seven sets of JCOE unit in Jiangsu, namely Guangzhou Panyu Zhujiang Steel Pipe (Jiangyin), Bohai Petroleum Equipment Nanjing Julong steel Pipe Company, Wuxi, Jiangsu Yulong Steel Pipe company (three sets of units), Yangzhou Yalian steel pipe Company and Zhangjiagang sand Jinzhou pipeline Limited; there are ten sets of UOE / JCOE units in the Yangtze River Delta region, total capacity of 2.13 million tons,, which is accounting for 40% of the country SAWL unit analysis by the unit, and accounting for 39 percent of domestic energy according to production statistics.

New materials developed to improve the corrosion resistance of carbon steel pipe

With the rapid development of the coastal petrochemical and power industries, the application of using seawater to replace the increasingly tense freshwater as industrial cooling medium can save a lot of fresh water resources, and get access to obtain significant economic and social benefits. However, due to the strong corrosion resistance of seawater, when using ordinary carbon steel or stainless steel tubes, water as the cooling medium will cause serious corrosion of the tube bundle, which can significantly reduce the life of the heat exchanger. This not only increases the number of replacement equipment, but also because of equipment failure causing equipment downtime too often and making the economic benefits reduced.
Under normal circumstances, to solve this problem, the pipe need to be done material upgrading, and upgrade materials mainly uses copper-nickel alloy and titanium tubes. Due to the high production cost of titanium tubes, it is difficult to be accepted by many users to, and copper-nickel alloy may cause corrosion due to serious pollution of seawater.
For the heat exchanger, its development has been largely relying on the adoption of the new material. Under many occasions, serious corrosion appears, the measures mainly adopted are:one surface corrosion, two is the choice of the new corrosion resistant material. The corrosion current application of new materials is mainly titanium tube, Hastelloy, super duplex stainless steel, zirconium tubes. These materials have good corrosion resistance, but their common drawback is the device cost is too high, so that the general business  is difficult to accept.
To solve the practical problems, there are companies combining the carbon steel pipe, stainless steel pipe with relatively low cost materials and thin-walled titanium tubes with strong corrosion resistance together, being applied to heat exchange equipment, and developed the desired anti-corrosion effect, the manufacturing cost is relatively low (+20 titanium steel, titanium and titanium tube was 40% + austenitic stainless steel, pure titanium pipe of 60%) and the use of the same performance and titanium tube heat exchanger tube bundle successfully. Compared with ordinary carbon steel pipe, has the following outstanding advantages:
(1) The superior corrosion resistance. In the medium offshore seawater heat exchanger tube bundle, the corrosion resistance of titanium tube is incomparable to any other pipe, composite pipe is the use of titanium tubes to achieve the advantages of corrosion-resistant, easy to scale, easy to plug, sea easy attachment of biological effects.
(2) reduce the cost of anti-corrosion materials. Composite pipe heat exchanger using thin-walled titanium tube bundles to meet corrosion requirements and use steel or stainless steel as the strength of the body, to the use of titanium tube heat exchanger effectiveness and cost much less than the latter.
(3) reduce maintenance costs. In the heat transfer area 700m2 meter under the same conditions, a flat carbon steel tubes annual maintenance cost of about 40,000 yuan, while the composite tube bundle corrosion maintenance cost is almost zero.
(4) extend the service life. Common organic preservative bundle the general life of 1 to 2 years, and titanium composite tube bundle life of over 10 years.
(5) conservation of freshwater resources to reduce overall energy consumption. Social and economic benefits using seawater were significantly higher than fresh water. Because seawater is lower than the ambient temperature 6 ~ 10 ℃, while circulating the water temperature higher than the ambient temperature is 3 ~ 5 ℃, the temperature difference between the two composite above 10 ℃, and the overall cost of the circulating water system is much higher than seawater. Meanwhile, since the surface of the circulating water will produce microbial attachment bundle and fouling can reduce heat transfer efficiency, and the titanium composite pipe can be effectively prevented in order to avoid adhesion of microorganisms to reduce heat transfer efficiency.