2015年10月31日星期六

Canadian raw material price index rises in September while industrial price index drops

According to Statistics Canada, the Industrial Product Price Index (IPPI) declined 0.3 percent in September, while the Raw Materials Price Index (RMPI) rose 3.0 percent in September. In September, the IPPI declined 0.3 percent for the second consecutive month. Among the 21 major commodity groups, 15 were up, 4 were down and 2 were unchanged. Higher prices for motorized and recreational vehicles (+0.6 percent) and primary non-ferrous metal products (+1.3 percent) helped moderate the decline in the IPPI in September. The gain in motorized and recreational vehicles was led by passenger cars and light trucks (+0.7 percent), motor vehicle engines and motor vehicle parts (+0.5 percent) as well as aircraft (+0.8 percent). Higher prices for motorized and recreational vehicles were closely linked to the depreciation of the Canadian dollar relative to the US dollar. The RMPI rose 3.0 percent in September, after declining 6.8 percent in August. Of the six major commodity groups, three were up and three were down. Higher prices for metal ores, concentrates and scrap (+1.1 percent) contributed to the increase in the RMPI.

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Suggested Reading:Titanium alloys are generall classified into four main categories

China’s steel plate imports down 25.8 percent in September

In September this year, China’s steel import volumes of steel bars, angles/channels, steel plate, and steel pipes and hollow sections amounted to 90,000 mt, 20,000 mt, 850,000 mt, and 30,000 mt, down 18.5 percent, 46.7 percent, 25.8 percent, and 25.1 percent, respectively, year on year, as announced by Chinese customs. In the January-September period of the current year, China’s import volumes of steel bars, angles/channels, steel plate, and steel pipes and hollow sections amounted to 800,000 mt, 280,000 mt, 8.21 million mt, and 280,000 mt, decreasing by 13.3 percent, 13.3 percent, 10.8 percent and 23.5 percent, respectively, year on year. In September this year, China imported 1.01 million mt of finished steel, down 25.8 percent year on year, while the finished steel import volume in the January-September period of the current year totaled 9.73 million mt, down 11.6 percent year on year, as previously announced by Chinese customs.

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Suggested Reading:Canadian raw material pprice index rises in September while industrial price index drops

Service center shipments continue to decline in US and Canada

The Metals Service Center Institute (MSCI) reported Thursday that steel shipments declined from 2014 levels in September for both the United States and Canada. Inventory positions also deteriorated in both countries. In September 2015, US service center steel shipments decreased by 10.9 percent from September 2014. Steel product inventories decreased 1.6 percent from September a year ago. Meanwhile, Canadian service center shipments of steel products decreased by 8.7 percent from September 2014. Steel product inventories decreased 3.3 percent from September a year ago.
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Suggested Reading:Vales iron ore inventories to fall 10 percent in 2016

Vale’s iron ore inventories to fall 10 percent in 2016

Brazilian iron ore producer Vale said this week during a conference call with analysts that the company’s iron ore inventories are expected to fall 10 percent in 2016, year-on-year, as a result of shipments of old inventory from its South System mines in the region of Vargem Grande, in the state of Minas Gerais. According to the company’s director of ferrous, Peter Poppinga, Vale’s iron ore inventories are now reaching between 55 and 56 million mt, 3 million mt down in Q3, when compared to Q2. The company also said it expects to produce iron ore at a cost of $10/mt in all its mining systems “in the near future.” The price target includes the mine, the benefaction and the transportation of the iron ore to the port in Brazil. As of Q3, Vale’s cash cost FOB port for iron ore finex ex-royalties reached $12.70/mt, down from $15.80/mt in Q2, same conditions. As for the $10/mt cost estimate, Vale considered the start-up of its SD11 iron ore project. Vale’s finance and investor relations director Luciano Siani said Vale’s raised about $3 billion with sale of assets. The executive rejected the idea that Vale could be pressured to close the sale of other assets, as a result of the completion of its SD11 iron ore project.

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Suggested Reading:Chinas steel plate imports down 25.8 percent in September

2015年10月29日星期四

What is Titanium alloy?

Titanium alloys are metals that contain a mixture of titanium and other chemical elements. Such alloys have very high tensile strength and toughness (even at extreme temperatures). They are light in weight, have extraordinary corrosion resistance and the ability to withstand extreme temperatures. However, the high cost of both raw materials and processing limit their use to military applications, aircraft, spacecraft, medical devices, highly stressed components such as connecting rods on expensive sports cars and some premium sports equipment and consumer electronics.
Although "commercially pure" titanium has acceptable mechanical properties and has been used for orthopedic and dental implants, for most applications titanium is alloyed with small amounts of aluminium and vanadium, typically 6% and 4% respectively, by weight. This mixture has a solid solubility which varies dramatically with temperature, allowing it to undergo precipitation strengthening. This heat treatment process is carried out after the alloy has been worked into its final shape but before it is put to use, allowing much easier fabrication of a high-strength product.

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Suggested Reading:The welding of steel

The properties of titanium alloy

Generally, alpha-phase titanium is the more ductile phase and beta-phase titanium is stronger yet less ductile. Alpha-beta-phase titanium has a mechanical property which is in between both.
Titanium dioxide dissolves in the metal at high temperatures, and its formation is very energetic. These two factors mean that all titanium except the most carefully purified has a significant amount of dissolved oxygen, and so may be considered a Ti-O alloy. Oxide precipitates offer some strength (as discussed above), but are not very responsive to heat treatment and can substantially decrease the alloy's toughness.

Many alloys also contain titanium as a minor additive, but since alloys are usually categorized according to which element forms the majority of the material, these are not usually considered to be "titanium alloys" as such. See the sub-article on titanium applications.

Titanium alone is a strong, light metal. It is stronger than common, low-carbon steels, but 45% lighter. It is also twice as strong as weak aluminium alloys but only 60% heavier. Titanium has outstanding corrosion resistance to sea water, and thus is used in propeller shafts, rigging and other parts of boats that are exposed to sea water. Titanium and its alloys are used in airplanes, missiles and rockets where strength, low weight and resistance to high temperatures are important. Further, since titanium does not react within the human body, it and its alloys are used to create artificial hips, pins for setting bones, and for other biological implants. See Titanium#Orthopedic implants.

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Suggested Reading:What is Titanium alloy?

Mild and low-carbon steel

Mild steel[clarification needed], also known as plain-carbon steel, is now the most common form of steel because its price is relatively low while it provides material properties that are acceptable for many applications. Low-carbon steel contains approximately 0.05–0.15% carbonmaking it malleable and ductile. Mild steel has a relatively low tensile strength, but it is cheap and easy to form; surface hardness can be increased through carburizing.
It is often used when large quantities of steel are needed, for example as structural steel. The density of mild steel is approximately 7.85 g/cm3 (7850 kg/m3 or 0.284 lb/in3) and the Young's modulus is 210 GPa (30,000,000 psi).

Low-carbon steels suffer from yield-point runout where the material has two yield points. The first yield point (or upper yield point) is higher than the second and the yield drops dramatically after the upper yield point. If a low-carbon steel is only stressed to some point between the upper and lower yield point then the surface may develop Lüder bands.[6] Low-carbon steels contain less carbon than other steels and are easier to cold-form, making them easier to handle.
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Suggested Reading:The properties of titanium alloy

Transition temperature

The crystal structure of titanium at ambient temperature and pressure is close-packed hexagonal α phase with a c/a ratio of 1.587. At about 890 °C, the titanium undergoes an allotropic transformation to a body-centred cubic β phase which remains stable to the melting temperature.
Some alloying elements raise the alpha-to-beta transition temperature(i.e., alpha stabilizers) while others lower the transition temperature (i.e., beta stabilizers). Aluminium, gallium, germanium, carbon, oxygen and nitrogen are alpha stabilizers. Molybdenum, vanadium, tantalum, niobium, manganese, iron, chromium, cobalt, nickel, copper and silicon are beta stabilizers.
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Suggested Reading:Mild and low-carboon steel

Titanium alloys are generally classified into four main categories

Alpha alloys which contain neutral alloying elements (such as tin) and/ or alpha stabilisers (such as aluminium or oxygen) only. These are not heat treatable. Examples include:[3] Ti-5AL-2SN-ELI, Ti-8AL-1MO-1V.
Near-alpha alloys contain small amount of ductile beta-phase. Besides alpha-phase stabilisers, near-alpha alloys are alloyed with 1–2% of beta phase stabilizers such as molybdenum, silicon or vanadium. Examples include:[3] Ti-6Al-2Sn-4Zr-2Mo, Ti-5Al-5Sn-2Zr-2Mo, IMI 685, Ti 1100.

Alpha and beta alloys, which are metastable and generally include some combination of both alpha and beta stabilisers, and which can be heat treated. Examples include:[3] Ti-6Al-4V, Ti-6Al-4V-ELI, Ti-6Al-6V-2Sn.

Beta and near beta alloys, which are metastable and which contain sufficient beta stabilisers (such as molybdenum, silicon and vanadium) to allow them to maintain the beta phase when quenched, and which can also be solution treated and aged to improve strength. Examples include:[3] Ti-10V-2Fe-3Al, Ti-13V-11Cr-3Al, Ti-8Mo-8V-2Fe-3Al, Beta C, Ti-15-3.
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Suggested Reading:Transition temperature

2015年10月24日星期六

The welding of steel

Gas tungsten arc welding is most commonly used to weld stainless steel and nonferrous materials, such as aluminum and magnesium, but it can be applied to nearly all metals, with a notable exception being zinc and its alloys. Its applications involving carbon steels are limited not because of process restrictions, but because of the existence of more economical steel welding techniques, such as gas metal arc welding and shielded metal arc welding. Furthermore, GTAW can be performed in a variety of other-than-flat positions, depending on the skill of the welder and the materials being welded.
For GTAW of carbon and stainless steels, the selection of a filler material is important to prevent excessive porosity. Oxides on the filler material and workpieces must be removed before welding to prevent contamination, and immediately prior to welding, alcohol or acetone should be used to clean the surface. Preheating is generally not necessary for mild steels less than one inch thick, but low alloy steels may require preheating to slow the cooling process and prevent the formation of martensite in the heat-affected zone. Tool steels should also be preheated to prevent cracking in the heat-affected zone. Austenitic stainless steels do not require preheating, but martensitic and ferritic chromium stainless steels do. A DCEN power source is normally used, and thoriated electrodes, tapered to a sharp point, are recommended. Pure argon is used for thin workpieces, but helium can be introduced as thickness increases

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Suggested Reading:SEKO Machinery to a dinner party for the double ninth festival charity

SEKO Machinery to a dinner party for the double ninth festival charity

The Double Ninth Festival of 2015 falls on October 21. There is no holiday for this traditional festival.
On October 23, FuYu Village village committee for the double ninth festival charity banquet, donate money to a lonely old man, the invited the company to participate.

Held on the 9th day of the 9th lunar month, Double Ninth Festival is also called Double Ninth Festival. In Chinese, nine is regarded as the number of Yang (which means masculine as opposed to Yin which is feminine). The ninth day of the ninth month is the day that has two Yang numbers, and 'chong' in Chinese means double which is how the name Chongyang was created. It is a day for people to eat Chongyang cake, drink chrysanthemum wine, climb mountains, and pay homage to chrysanthemums.




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Suggested Reading:Former employees, USW to receive $12 million in RG Steel bankruptcy settlement

2015年10月23日星期五

Introduction of laser welding operation

Like electron beam welding (EBW), laser beam welding has high power density (on the order of 1 MW/cm2) resulting in small heat-affected zones and high heating and cooling rates. The spot size of the laser can vary between 0.2 mm and 13 mm, though only smaller sizes are used for welding. The depth of penetration is proportional to the amount of power supplied, but is also dependent on the location of the focal point: penetration is maximized when the focal point is slightly below the surface of the workpiece
A continuous or pulsed laser beam may be used depending upon the application. Millisecond-long pulses are used to weld thin materials such as razor blades while continuous laser systems are employed for deep welds.

LBW is a versatile process, capable of welding carbon steels, HSLA steels, stainless steel, aluminum, and titanium. Due to high cooling rates, cracking is a concern when welding high-carbon steels. The weld quality is high, similar to that of electron beam welding. The speed of welding is proportional to the amount of power supplied but also depends on the type and thickness of the workpieces. The high power capability of gas lasers make them especially suitable for high volume applications. LBW is particularly dominant in the automotive industry.

Some of the advantages of LBW in comparison to EBW are as follows:

-the laser beam can be transmitted through air rather than requiring a vacuum

-the process is easily automated with robotic machinery

- x-rays are not generated

- LBW results in higher quality welds

A derivative of LBW, laser-hybrid welding, combines the laser of LBW with an arc welding method such as gas metal arc welding. This combination allows for greater positioning flexibility, since GMAW supplies molten metal to fill the joint, and due to the use of a laser, increases the welding speed over what is normally possible with GMAW. Weld quality tends to be higher as well, since the potential for undercutting is reduced.

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Suggested Reading: What is the laser welding?

What is the laser welding?

Laser beam welding (LBW) is a welding technique used to join multiple pieces of metal through the use of a laser. The beam provides a concentrated heat source, allowing for narrow, deep welds and high welding rates. The process is frequently used in high volume applications, such as in the automotive industry. It is based on keyhole mode welding or Penetration mode welding.

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Suggested Reading: The quality of gas tungsten arc welding

Former employees, USW to receive $12 million in RG Steel bankruptcy settlement

A federal judge approved Thursday a structured settlement of claims in RG Steel’s Chapter 11 bankruptcy case that gives USW-related entities about 70 percent of the $17.4 million total to be distributed to creditors.
The United Steelworkers (USW) joined a multi-party mediation process last year in an effort to recover as much as possible for workers and retirees who were affected by the company’s May 2012 bankruptcy filing.

“The USW did a good job in making the best of a bad situation. It’s sad that it had to come to this, and unfortunate that this has affected so many hard-working people,” said David Boyd, a USW Local 9477 retiree who was employed at Sparrows Point, Md. “But the union never gave up and kept fighting for what was right all the way to the very end.”

The USW’s share of the settlement comes to about $12 million, a sum that includes about $6.3 million in vacation and severance payments owed to about 4,000 workers at former RG Steel mills in Sparrows Point, Md., Warren, Ohio, and Wheeling, W.Va,, and at a coke-making facility in Follansbee, W.Va.

The settlement also includes payments of $2.4 million to a voluntary employee beneficiary association (VEBA) for workers at the Warren mill; $990,790 to the Steelworkers Health & Welfare Fund to cover more than $6 million in claims; more than $814,000 to the Steelworkers Pension Trust; $445,590.31 to a VEBA for workers at Wheeling-Pitt, a predecessor to RG Steel; $480,000 to cover unpaid medical claims; and about $54,000 in severance for workers at an Allenport, Pa., mill that closed in 2008.

“This settlement doesn’t make up for the fact that so many people have suffered,” Boyd said. “But if we hadn’t had the union fighting for us, we could have ended up with nothing.”

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Suggested Reading:Brazilian steel sales and output decline in September

Brazilian steel sales and output decline in September

Brazilian sales of steel in September fell 20.7 percent, year-on-year, reaching 1.5 million mt,
according to data released on Monday by the nation’s steel institute, IABr. The trade group said domestic apparent consumption in the ninth month of the year declined 24.1 percent, year-on-year, to 1.7 million mt, while imports reached 224,000 mt at $188 million. IABr said Brazil’s crude steel production in September totaled 2.5 million mt, 13 percent down, year-on-year. Finished steel production in September reached 1.7 million mt, 23.1 percent down, year-on-year. According to IABr, accumulated steel sales for the period of January to September was 14.2 million mt, 14.3 percent down, year-on-year. Domestic apparent consumption and imports in the period reached 16.9 million mt and 2.8 million mt, respectively, with the first diminishing 14 percent, year-on-year. So far in the year, crude steel output reached 25.3 million mt, 1.2 percent down, year-on-year. Finished steel production in the nine-month period totaled 17.4 million mt, 8.2 percent down, year-on-year. Reflecting a more appreciated USD and the still weak domestic market, IABr said exports in September reached 1.6 million mt in volume and $680 million in revenues. From January to September, exports totaled 10 million mt and $5.2 billion, up 48.6 percent in terms of volume and 6.1 percent in terms of revenue, both on an year-on-year basis.

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Suggested Reading:Introduction of laser welding operation

2015年10月21日星期三

Xi jinping chairman and Mrs Peng liyuan visited to the UK

SEKO Machinery Company’s employees today to watch the President visit to the UK's news, all of them were very extcied.
China's President Xi Jinping has said he believes his visit will lift UK-China relations to a "new height".
The UK and China were becoming more interdependent and a "community of shared interests," he said on the first full day of his four-day visit.
At a Buckingham Palace banquet, the Queen said this was a "very special year for our bilateral relationship".

The visit comes amid job losses in the UK steel sector, with cheap Chinese imports among factors being blamed.
The Queen described President Xi Jinping’s State visit to Britain as a “defining moment” in the future of Sino-UK relations last night as the Chinese leader spoke of the “everlasting friendship” between the two countries.
The Queen described the first State visit by a Chinese premier for 10 years as “a milestone in the unprecedented year of co-operation and friendship between the United Kingdom and China” as David Cameron and George Osborne pursue a policy of making Britain China’s most important European trading partner.

Among the guests were Prime Minister David Cameron, Chancellor George Osborne, the Archbishop of Canterbury Justin Welby and the governor of the Bank of England Mark Carney.

Members of the royal family who attended included the Duke of York, the Princess Royal and the Earl and Countess of Wessex. -------------SEKO Machinery Company reported

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Suggested Reading: The development of gas tungsten arc welding

The quality of gas tungsten arc welding

Gas tungsten arc welding, because it affords greater control over the weld area than other welding processes, can produce high-quality welds when performed by skilled operators. Maximum weld quality is assured by maintaining cleanliness—all equipment and materials used must be free from oil, moisture, dirt and other impurities, as these cause weld porosity and consequently a decrease in weld strength and quality. To remove oil and grease, alcohol or similar commercial solvents may be used, while a stainless steel wire brush or chemical process can remove oxides from the surfaces of metals like aluminum. Rust on steels can be removed by first grit blasting the surface and then using a wire brush to remove any embedded grit. These steps are especially important when negative polarity direct current is used, because such a power supply provides no cleaning during the welding process, unlike positive polarity direct current or alternating current.[20] To maintain a clean weld pool during welding, the shielding gas flow should be sufficient and consistent so that the gas covers the weld and blocks impurities in the atmosphere. GTAW in windy or drafty environments increases the amount of shielding gas necessary to protect the weld, increasing the cost and making the process unpopular outdoors.
The level of heat input also affects weld quality. Low heat input, caused by low welding current or high welding speed, can limit penetration and cause the weld bead to lift away from the surface being welded. If there is too much heat input, however, the weld bead grows in width while the likelihood of excessive penetration and spatter increase. Additionally, if the welding torch is too far from the workpiece the shielding gas becomes ineffective, causing porosity within the weld. This results in a weld with pinholes, which is weaker than a typical weld.

If the amount of current used exceeds the capability of the electrode, tungsten inclusions in the weld may result. Known as tungsten spitting, this can be identified with radiography and can be prevented by changing the type of electrode or increasing the electrode diameter. In addition, if the electrode is not well protected by the gas shield or the operator accidentally allows it to contact the molten metal, it can become dirty or contaminated. This often causes the welding arc to become unstable, requiring that the electrode be ground with a diamond abrasive to remove the impurity.

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Suggested Reading: Xi jinping chairman and Mrs Peng liyuan visited to the UK

2015年10月19日星期一

The development of gas tungsten arc welding

After the discovery of the short pulsed electric arc in 1800 by Humphry Davy and of the continuous electric arc in 1802 by Vasily Petrov, arc welding developed slowly. C. L. Coffin had the idea of welding in an inert gas atmosphere in 1890, but even in the early 20th century, welding non-ferrous materials such as aluminum and magnesium remained difficult because these metals react rapidly with the air and result in porous, dross-filled welds. Processes using flux-covered electrodes did not satisfactorily protect the weld area from contamination. To solve the problem, bottled inert gases were used in the beginning of the 1930s. A few years later, a direct current, gas-shielded welding process emerged in the aircraft industry for welding magnesium.
Russell Meredith of Northrop Aircraft perfected the process in 1941. Meredith named the process Heliarc because it used a tungsten electrode arc and helium as a shielding gas, but it is often referred to as tungsten inert gas welding (TIG); in parts of the world where tungsten is called wolfram, it is known as WIG. The American Welding Society's official term is gas tungsten arc welding (GTAW). Linde Air Products developed a wide range of air-cooled and water-cooled torches, gas lenses to improve shielding, and other accessories that increased the use of the process. Initially, the electrode overheated quickly and, despite tungsten's high melting temperature, particles of tungsten were transferred to the weld.[6] To address this problem, the polarity of the electrode was changed from positive to negative, but the change made it unsuitable for welding many non-ferrous materials. Finally, the development of alternating current units made it possible to stabilize the arc and produce high quality aluminum and magnesium welds.

Developments continued during the following decades. Linde developed water-cooled torches that helped prevent overheating when welding with high currents. During the 1950s, as the process continued to gain popularity, some users turned to carbon dioxide as an alternative to the more expensive welding atmospheres consisting of argon and helium, but this proved unacceptable for welding aluminum and magnesium because it reduced weld quality, so it is rarely used with GTAW today. The use of any shielding gas containing an oxygen compound, such as carbon dioxide, quickly contaminates the tungsten electrode, making it unsuitable for the TIG process. In 1953, a new process based on GTAW was developed, called plasma arc welding. It affords greater control and improves weld quality by using a nozzle to focus the electric arc, but is largely limited to automated systems, whereas GTAW remains primarily a manual, hand-held method.[10] Development within the GTAW process has continued as well, and today a number of variations exist. Among the most popular are the pulsed-current, manual programmed, hot-wire, dabber, and increased penetration GTAW methods.
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Suggested Reading:Production and Distribution of Iron Ore around the World(2

How to operate the gas tungsten arc welding machine?

Manual gas tungsten arc welding is a relatively difficult welding method, due to the coordination required by the welder. Similar to torch welding, GTAW normally requires two hands, since most applications require that the welder manually feed a filler metal into the weld area with one hand while manipulating the welding torch in the other. Maintaining a short arc length, while preventing contact between the electrode and the workpiece, is also important.
To strike the welding arc, a high frequency generator (similar to a Tesla coil) provides an electric spark. This spark is a conductive path for the welding current through the shielding gas and allows the arc to be initiated while the electrode and the workpiece are separated, typically about 1.5–3 mm (0.06–0.12 in) apart.

Once the arc is struck, the welder moves the torch in a small circle to create a welding pool, the size of which depends on the size of the electrode and the amount of current. While maintaining a constant separation between the electrode and the workpiece, the operator then moves the torch back slightly and tilts it backward about 10–15 degrees from vertical. Filler metal is added manually to the front end of the weld pool as it is needed.

Welders often develop a technique of rapidly alternating between moving the torch forward (to advance the weld pool) and adding filler metal. The filler rod is withdrawn from the weld pool each time the electrode advances, but it is always kept inside the gas shield to prevent oxidation of its surface and contamination of the weld. Filler rods composed of metals with a low melting temperature, such as aluminum, require that the operator maintain some distance from the arc while staying inside the gas shield. If held too close to the arc, the filler rod can melt before it makes contact with the weld puddle. As the weld nears completion, the arc current is often gradually reduced to allow the weld crater to solidify and prevent the formation of crater cracks at the end of the weld



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Suggested Reading:Production and Distribution of Iron Ore around the World(2

2015年10月17日星期六

The raw materials of iron and steel

Iron ores are rocks and minerals from which metallic iron can be economically extracted. The ores are usually rich in iron oxides and vary in color from dark grey, bright yellow, deep purple, to rusty red. The iron itself is usually found in the form of magnetite (Fe3O4, 72.4% Fe), hematite (Fe2O3, 69.9% Fe), goethite (FeO(OH), 62.9% Fe), limonite (FeO(OH).n(H2O)) or siderite (FeCO3, 48.2% Fe).
Ores containing very high quantities of hematite or magnetite (greater than ~60% iron) are known as "natural ore" or "direct shipping ore", meaning they can be fed directly into iron-making blast furnaces. Iron ore is the raw material used to make pig iron, which is one of the main raw materials to make steel. 98% of the mined iron ore is used to make steel. Indeed, it has been argued that iron ore is "more integral to the global economy than any other commodity, except perhaps oil".

Metallic iron is virtually unknown on the surface of the Earth except as iron-nickel alloys from meteorites and very rare forms of deep mantle xenoliths. Although iron is the fourth most abundant element in the Earth's crust, comprising about 5%, the vast majority is bound in silicate or more rarely carbonate minerals. The thermodynamic barriers to separating pure iron from these minerals are formidable and energy intensive, therefore all sources of iron used by human industry exploit comparatively rarer iron oxide minerals, primarily hematite.

Prior to the industrial revolution, most iron was obtained from widely available goethite or bog ore, for example during the American Revolution and the Napoleonic wars. Prehistoric societies used laterite as a source of iron ore. Historically, much of the iron ore utilized by industrialized societies has been mined from predominantly hematite deposits with grades of around 70% Fe. These deposits are commonly referred to as "direct shipping ores" or "natural ores". Increasing iron ore demand, coupled with the depletion of high-grade hematite ores in the United States, after World War II led to development of lower-grade iron ore sources, principally the utilization of magnetite and taconite. (Taconite is a rock whose iron content, commonly present as finely dispersed magnetite, is generally 25 to 30%.)

Iron-ore mining methods vary by the type of ore being mined. There are four main types of iron-ore deposits worked currently, depending on the mineralogy and geology of the ore deposits. These are magnetite, titanomagnetite, massive hematite and pisolitic ironstone deposits.

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Suggested Reading:The types of carbon steel

The introduction of iron

Iron is the world's most commonly used metal - steel, of which iron ore is the key ingredient, representing almost 95% of all metal used per year. It is used primarily in structural engineering applications and in maritime purposes, automobiles, and general industrial applications (machinery).
Iron-rich rocks are common worldwide, but ore-grade commercial mining operations are dominated by the countries listed in the table aside. The major constraint to economics for iron ore deposits is not necessarily the grade or size of the deposits, because it is not particularly hard to geologically prove enough tonnage of the rocks exist. The main constraint is the position of the iron ore relative to market, the cost of rail infrastructure to get it to market and the energy cost required to do so.

Mining iron ore is a high volume low margin business, as the value of iron is significantly lower than base metals. It is highly capital intensive, and requires significant investment in infrastructure such as rail in order to transport the ore from the mine to a freight ship. For these reasons, iron ore production is concentrated in the hands of a few major players.

World production averages two billion metric tons of raw ore annually. The world's largest producer of iron ore is the Brazilian mining corporation Vale, followed by Anglo-Australian companies Rio Tinto Group and then BHP Billiton. A further Australian supplier, Fortescue Metals Group Ltd has helped bring Australia's production to second in the world.

The seaborne trade in iron ore, that is, iron ore to be shipped to other countries, was 849m tonnes in 2004. Australia and Brazil dominate the seaborne trade, with 72% of the market. BHP, Rio and Vale control 66% of this market between them.

In Australia iron ore is won from three main sources: pisolite "channel iron deposit" ore derived by mechanical erosion of primary banded-iron formations and accumulated in alluvial channels such as at Pannawonica, Western Australia; and the dominant metasomatically-altered banded iron formation related ores such as at Newman, the Chichester Range, the Hamersley Range and Koolyanobbing, Western Australia. Other types of ore are coming to the fore recently, such as oxidised ferruginous hardcaps, for instance laterite iron ore deposits near Lake Argyle in Western Australia.

The total recoverable reserves of iron ore in India are about 9,602 million tones of hematite and 3,408 million tones of magnetite[citation needed].Chhattisgarh, Madhya Pradesh, Karnataka, Jharkhand, Odisha, Goa, Maharashtra, Andhra Pradesh, Kerala, Rajasthan and Tamil Nadu are the principal Indian producers of iron ore. World consumption of iron ore grows 10% per annum on average with the main consumers being China, Japan, Korea, the United States and the European Union.

China is currently the largest consumer of iron ore, which translates to be the world's largest steel producing country. It is also the largest importer, buying 52% of the seaborne trade in iron ore in 2004. China is followed by Japan and Korea, which consume a significant amount of raw iron ore and metallurgical coal. In 2006, China produced 588 million tons of iron ore, with an annual growth of 38%.

Guangdong Shunde Seko Machinery & Technology Co.,Ltd.www.gdseko.com
Lucy Xie

sevvice@gdseko.com
Skype:Lucy Xie,SEKO Machinery

Suggested Reading:The raw materials of iron and steel

Guangdong shunde SEKO Machinery Co.LTD.—— 5S mnagement

SEKO Machinery has been promoting 5S management, because the general manager Mr Nv Haihui to lead. 5S including seiri, seiton, seiso, seiketsu and shitsuke.It is held once a week a small comparison, once a month the big appraisal. And aslo set up a special 5S management committee, in order to make the managers and ordinary employees can be fully integrated into the 5S management, better for the standardization of enterprise management. Another set up the 5S special fund to motivate employees, to ensure the 5S results, make the whole company always maintain a clean and tidy appearance, with a thriving vitality!

Guangdong Shunde Seko Machinery & Technology Co.,Ltd.www.gdseko.com
Lucy Xie

sevvice@gdseko.com
Skype:Lucy Xie,SEKO Machinery

Suggested Reading:The introduction of iron

Comparison of standardized steels

Comparison of standardized steels


Time:2015-10-16 17:29:23