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Today is the first day to office in 2020 new year , and the first big good news was that Otai Special Steel have sales promotion for AISI 4140 preharded plate . We have more than 500 Tons stocklist in our warehouse with mixed size for thickness from 20MM to 180MM , we prepare this alloy steel AISI 4140 preharded plate to thanks our valued client for the support to our company in the past year of 2019 , and other special big thickness and different delivery conditions could be special ordered . If you have any interesting , please contact with me directly by e-mail : monica@otaisteel.com and whatsapp : +86 13711903397 , we will send you the quotation with best price as soon as possible .

In the past year of 2019 , we have sold more than 5000 Tons AISI 4140 preharded plate and round bar ,  4140PH is a chromium-manganese-molybdenum grade . This grade is delivered in a prehardened condition at a hardness level of 33/37HRC . The grade has a fully homogeneous martensitebainite microstructure .  4140PH grade has specific sulfur addition (0.060% typical) in order to increase strongly its machinability .

AISI 4140 preharded plate grade performs very well in drilling and in milling using high speed steel or carbide tools. The machinability of 4140PH is increased by a controlled sulfur addition which gives: • 500% increase in milling tool life (at constant cutting speed) • 300% increase in drilling speed • 30% increase in milling speed .

AISI 4140 preharded plate and steel bar, flat material can be used for as wide variety of applications where greater toughness and wear resistance is needed over lower carbon grades. Typical applications for 4140 tool steel uses include Components, Adapters, Arbors,strippers, holder blocks, mold bases, ejectors, back up and support tooling, fixtures, jigs, molds, cams, drill collars, Axle Shafts, Bolts, Crankshafts,stubs, couplings, reamer bodies, axles, shafting, piston rods, rams, hydraulic machinery shafts, gears, sprockets, gear racks, chain links, spindles, tool bodies, tool holders, tie rods, Connection Rods, Chuck Bodies, Collets, Conveyor Pins & Rolls, Ejector Pins, Forks, Gears, Guide Rods, Hydraulic Shafts & Parts,Lathe Spindles, Logging Parts, Milling Spindles, Motor Shafts, Nuts, Pinch Bars, Pinions, Pump Shafts,boring bars,tracks, slides, wear strips or parts, forming dies, brake dies, trim dies, bolsters, machinery parts and components, etc.

Tel: 0086-769-23190193

Fax: 0086-769-88705839

Email: jack@otaisteel.com

Our plastic mould steel is highly corrosion-resistant and used to process plastic moulds, which can contain chemically aggressive or abrasive fillers.

Happy new year! Time flies, the 2020 year has already come, Otai wishes you a prosperous and happy 2020.

I’d like to share the plastic mold steel with you, plastic mould steel, does it plastic or real steel? it’s real steel.

All production mold tools ought to be made out of high-quality metals suitable BS, ASTM or DIN standards.

Several unique metals are occasionally utilized.

 the principal Plastic mould steel employed fall into three types:

 Alloy Steel

Alloy steels are generally used in cavities as well as for any plates which come into straight exposure to the mould materials. Alloy steels may be utilized in their softer condition or might be entirely hardened based on the utility.

Typically, all cavity components are generally totally hardened, because they should stand up to cyclical substantial loading, wear and thermal strains. Cavity holding plates and various other shuts off places are typically manufactured from the soft model. They just don’t want the greater strength and wear prevention that the hardened metal provides but they do present a better standard of shelter against damage than would mild metal.

 Mild Steel

This metal is normally utilized for all other tool plates. Mild steel mustn’t be used in cavity inserts or get in touch with the mould material. It ought to never be applied exactly where it should be subject to extreme sliding conditions, etc for the quality control reason. Occasionally manufacturers prefer to try a higher- carbon-content metal on long-running tasks to get greater ability to resist damage.

 Beryllium-Copper

This kind of material is an alloy of beryllium and copper. Beryllium is normally preferred because of its strength and copper for the thermal characteristics. It is going to conduct heat away speedily plus much more easily than steel.

Otai Special steel company is a stable and reliable supplier for fortune 500 companies at home and abroad, such as Thyssenkrupp, china north industries group corporation limited. waiting for your good news.

Mr Jack Tan

Tel: 0086-769-23190193

Fax: 0086-769-88705839

Email: jack@otaisteel.com

We are the 4340 steel suppliers, we not only supply this alloy steel, but also the carbon steel, tool steel and high speed steel. We are happy and proud for we are expert in this steel material field for more than 20years.

Otai is as the 4340 steel suppliers, we always keep on being the one who can be reliable for all of you guys.
Today I would like to talk about “made in China”. Many many years ago, you may think that when mentioned “make in China”, Many people’s first impressions are poor quality and bad reputation.
But now not any more, in fact, China in last decades has developed super fast. Not only fast a little but fast in a big development. In many ways, such as, countries, development construction and technology.

Next I would like to summarize the important developments of China in 2019. As Chinese, we are very proud of seeing the prosperity of our motherland. We are proud because we and ours are made in China.
1) “Chang’e-4″ landed autonomously on the back of the moon, returning the world’s first close-up image of the moon back.
2) China Aerospace successfully completed its first maritime launch.
3) The 50th and 51st Beidou navigation satellite was successfully launched
4) The Great Wall V Yaoyao 3 launch vehicle was successfully launched
5) China’s 5G commercial use
6) The new super-long version of the ” Renaissance EMU” train doubled its capacity.
7)”Water Cube” changed to “Ice Cube” for the 2022 Beijing Winter Olympics
8) China’s “Bridge King” Yangsi Port Yangtze River Bridge was completed and opened to traffic.

In addition, China rectifies and reforms Chinese steel mills in 2019. And some small-scale steel mills and unqualified steel mills were closed. These are all improvements that the motherland has made for the quality and development of Chinese manufacturing.
The previous steel material market environment was quite chaotic. Some 4340 steel suppliers may attract customers with lower prices, and take the customers benefits no consideration. The 4340 steel suppliers find the steel mills with small-scale or unqualified to produce it.

Of course, this does not mean that such problems have been completely avoided after rectification. Everyone has different values, so each company has different culture and values. We cannot guarantee or require that someone need to be reliable, but our OTAI Special Steel insist on being ourselves. We are being the one who can be reliable by our dear customers. This is the most basic and best we could do for them.

Tel: 0086-769-23190193

Fax: 0086-769-88705839

Email: jack@otaisteel.com

H13 application –Chapter 8

H13 steel is the most widely used of the hot work mold steel in the world. H13 has great heat intensity properties, hardness and wear resistance. The toughness and anti-fatigue performance of H13  are good.H13 is widely used to make all kinds of hammer dies, hot-extrusion dies and etc. H13  -Hot die steel needs to sustain huge impulse load, friction and high-temperature oxidation. But h13 something always happens during work time. Such as the crack, dent, abrasion, formation of cracking and etc. The chemical composition chart of H13 die steel as below.

Its characteristics of chemical composition of   H13

H13  carbon content can make sure the high hardness, toughness and other properties.

Adding the elements Cr, Mn, Si, Mn, H13  can make the hardenability get better to change the nature and shape of the oxide in the time of steel become solidification. H13 That move can avoid the formation of low melting point Fes on the grain boundary. Instead, existence as Mns with certain plasticity. Then it will clean out the bad influence of sulfur to make the hot workability of H13 mold steel. Adding the elements of Mo, V to make it harden secondary. And it can enhance temper resistance.

The factors of failure-H13 STEEL

H13  is a complicated question. But we can analysis it on four ways of material, design, manufacture and use.

• Chemical composition and the quality of material of H13

H13 steel belongs to the type of graphitic alloy steel. H13 have  so many nonmetallic inclusion in it. And H13 has the defects of the center be loosen and etc. H13  will make the strength, toughness and etc get down. And the quality of H13 steel has two levels for common and high-quality. High quality H13 steel is made from high technology and material. H13 has better toughness and thermal fatigue property. However, the common one needs the processing of forging. H13 will destroy the big non-metallic inclusion and make the carbide get small.

WhatsApp: +86-769-23190193

Tel: +86-769-23190193

Fax: +86-769-88705839

Email: Jack@otaisteel.com

OTAI, as special steel supplier, works at steel industry over 20 years, export special steel to more than 30 countries include Europe, North America, South American, Middle East and Asia. OTAI is stable and reliable special steel supplier for Fortune 500 companies at home and abroad, such as Thyssenkrupp, China North Industries Group Corporation Limited. OTAI supply special steel for US oil field giant and one military industry well-known enterprise. OTAI steel materials meet DIN / ASTM / EN / JIS etc different international standards.

We are familiar about China market, have abundant knowledge at steel industry, and we have confidence about the material we supply, but we understand our customer do not trust us until they receive our material. As a steel supplier, for business cooperation, the most important and most difficult point is how to start the first order, especially when the buyer already have stable steel supplier. This article I would like share an Argentina customer’s story.

Argentina customer story, try to be their alternative steel supplier

This Argentina customer is important steel supplier in local market, they import steel in China, Turkey, Brazil and America. They also sell special steel 1045, 4140, 4340, D2, H13, P20, all mentioned are our main product. I try to contact this company since one year ago. I shared with them our company information, video, certification, inspection report, price promotion information, shipping information, and price trend analysis, try to show them OTAI Steel is professional steel supplier. The buyer read each of my email, but always keep silence. Until last month, I shared with them 4340 SGS inspection report and our sales data in Latin American market, the buyer Mr Alex reply me, they already have stable steel supplier, worked with them smoothly, and will not change supplier this moment.

I admit I am a sales person not easy to give up. I replied him an email the same day.

Dear Alex:

We just hope can be your secondary source.

I understand you do not want spend additional time and energy to explore new supplier. I worked as international purchaser before. Our supply chain was fragile when we are limited to a single supplier, I remember we have face problems as follow:

1) We could not ship the order to customer because quality issue of one key part (sole supplier) quality issue.

2) Customer increase order a lot, lead to bad result that we cannot fulfil the order in time.

3) Suppler increase price in a sudden and not reasonable, no enough time to explore new supplier, then have to cut our profit.

4) Our company missed high-quality customers due to the supplier’s non-cooperation.

All above lead to us must explore 1-2 alternative suppliers for any material since then.

OTAI hope can be your alternative special steel supplier. You can send us RFQ, then we will send you quotation, then you can compare our price with currently steel supplier. We also can send you samples for inspection.

If our price accepted, our quality approved, I believe, your currently steel supplier also will provide you better price, more stable quality, better communication as well.

That night, I received RFQ from this customer, about plastic mold steel P20 and 1.2738. We discuss details, and Mr Alex consider a trail order to see our material quality. That’s a good start. We will be qualified alternative special steel supplier.

Tel: 0086-769-23190193

Fax: 0086-769-88705839

Email: jack@otaisteel.com

The fluctuation of steel prices being  narrowed throughout 2019 , the pace of changes in prices quickly , and both the price and the industry’s profit center was fell in 2019.

Chinese Lunnar Year coming soon ( 26-Jan,2020 ), there is about 10-20 days holiday for Chinese Manufacture Industry. Here we talk about the Alloy steel  price infulecing factors 2 weeks  before and after Spring Festival .

The Factor of  Alloy steel USD unit price goes up :

• The average freight cost higher .

It is shipping season before Chinese Spring festival ,there is many vessel shchedule line will stop shipment or reduce their shipment line during Chinese Festival holiday .

As you know ,the price will go up in great shipment demand . According the newest offer from our shipment agent ,all the shipment cost by sea was go up 30% at least . Some shipment line ‘s freight twice as much as usual . (such as the Freight from Shanghai to Dubai ： 40GP ：800 USD on Oct.， now it is 1700 USD )

If the the Alloy steel offer base on CIF trade terms ,the offer will be higher even EXW price keep same as before .

• Machined process fee /Heat treatment cost /Domestic cost higher than usual

The new year coming soon ,and all the machined factory or heat treatment shop being crazy busy . And it is easy suffer Labor shortage before the Spring holiday . There is too many drivers for heavy trucks  also will have a holiday and back to hometown in advance ,it will lead to difficult to found a driver to help us shipment the Alloy steel from warehouse to Loading port .

Many production workers will leave their job ,and  look for a new job after Spring Holiday .It will lead to the labor cost higher than before ,then leadto the processing fee higher a little than usual .

Those reason have some influence of alloy steel order which need to processing again , such as do the Quenching and Tempering process ,or milling /Turning  process .

• The USD & RMB currency rate go down compared with Nov.2019 .

Ms Elwa Lee

Mobile/WhatsApp: 0086-15899675236

Tel: 0086-769-23190193

Fax: 0086-769-88705839

Email: Elwa@otaisteel.com

A36 carbon steel plate belongs to carbon steel. it is usually used in construction. A36 carbon steel’s strength, formability, and excellent welding properties make it suitable for a large variety of applications.

A36 carbon steel plate belongs to carbon steel. it is usually used in construction. A36 carbon steel’s strength, formability, and excellent welding properties make it suitable for a large variety of applications, including welding, fabricating, and bending. A36 Steel is available from otai Steel in angles, flats, plates, and sheets.

A36 carbon steel plate is known for its superior mechanical properties over commodity grades of merchant bar. The products are made to specific chemistry and mechanical properties ranges, allowing them to be used in engineered applications. Resulting shafts, axles, and gears can be used in the automotive industry and agriculture equipment.

We have a customer from Jordan, he sends me the email about the requirements of the quotation, bought the a36 carbon steel plate, Size: 8 -12mm x 1-meter x 2 meters. Quantity/ 2 each. it is a trade and engineering supplier company, our customer is satisfied with our product.

The property of the a36 carbon steel plate

• Popular steel plate grade used for a variety of structural applications.
• Available for heavy steel plate applications in up to 18” thickness.
• May have multiple specs certified on Mill Test Report, but guaranteed to be certified to meet ASTM A36.
• Ability to be riveted, bolted or welded.

Due to its wide variety of uses ,Otai Steel keeps a ready stock of the standard sizes of the A36 carbon steel plate, but other sizes may be available for special orders., Otai steel is a stable and reliable supplier for fortune 500 companies at home and abroad, such as thyssenkrupp, china north industries group corporation limited. Otai exports various tool steel and alloy to more than 30 countries from Europe and American, Middle East, and Asia. our steel materials meet DIN/ ASTM/EN/JIS etc different international standards. Welcome to connect with me.

Mr Jack Tan

Tel: 0086-769-23190193

Fax: 0086-769-88705839

Email: jack@otaisteel.com

_{Our H13 STEEL -chapter 7}

_{We can still easily understand the alloy carbide phase in H13 steel from the Fe-Cr-C ternary phase diagram. According to the phase diagrams of the ternary isothermal sections of the Fe-Cr-C series at 700 ℃ [18 ~ 20] and 870 ℃ [9], for 0.4% C steel, (FeCr) 3C (M3C) and (CrFe) 7C3 (M7C3) type alloy carbide. Note that on the 870 ° C chart, M23C6 will only appear if the Cr content is greater than 11%). In addition, according to the vertical section of the Fe-Cr-C ternary system at 5% Cr, the steel containing 0.40% C is an α phase (about 1% Cr solid solution) and (CrFe) 7C3 alloy C compound in the annealed state. When heated above 791 ° C, austenite A is formed and enters the (α + A + M7C3) three-phase region, and enters the (A + M7C3) two-phase region at about 795 ° C. (CrFe) 7C3 disappears at about 970 ° C. Enter single phase A area. When the matrix contains ﹤ 0.33%, the three-phase region (M7C3 + M23C6 and A) only exists at about 793 ° C, and enters the (A + M7C3) region (at 0.30% C) at 796 ° C, and will remain until the phase. The residual M7C3 in the steel has the effect of preventing A grains from growing. Nilson proposed that for a 1.5% C-13% Cr component alloy, less stable (CrFe) 23C6 does not form [20]. Of course, the analysis of Fe-Cr-C ternary system alone will have some deviations, and the effect of adding alloy elements must be considered.}

_{Kindly reminder :}

Designation by Standards Mat. No. DIN EN AISI 1.2344 X40CrMoV51 X40CrMoV51 H13 Chemical Composition (in weight %) C Si Mn Cr Mo Ni V W Others 0.39 1.00 0.38 5.15 1.35 – 1.00 – – Description This alloy is one of the hot work, chromium type tool steels. It also contains molybdenum and vanadium as strengthening agents. The chromium content assists this alloy to resist softening if used at higher temperatures. Secondary hardening steels with good tempering reistance. It maintains …

WhatsApp: +86-769-23190193

Tel: +86-769-23190193

Fax: +86-769-88705839

Email: Jack@otaisteel.com

In 2020 new year ,different exihibitions under processing now .and I want to share a fare news of  foundry, diecasting and forge industry exihibition .

As you know ,Otai as the raw material stockist of alloy steel /Tooling steel, we set up long-term cooperation with fountry or forged supplier / mill factories ,and also keep a partner with our docustomer who professional on Diecasting / forged industry .

Biggest trade exhibition for foundry, diecasting and forge industry

Guangzhou International Foundry Diecasting and Forge Industry Exhibition:This international is unique as it will make the foundry diecasting and forge industry conscious of the latest and technologies and the developmental changes which are taking place.

Professional experts from all over the world will take an active part in this Diecasting and Forge  expo and will make this expo more advanced and more popular.  It will bring the industries related to automobile, aerospace, motorcycle, die casting, foundry, electrical appliances, and computer accessories under one roof.

The Diecasting and Forge  Exhibition will exhibit the latest products and services including Cool Die-casting Machines.  Heat Diecasting Machine . Low pressure Diecasting Machine, Peripheral Equipments . Fittings of Diecasting Machines . Gravity Casting .Hydraulic Press Machine, Oil Press Machine, Pattern Making, Equipment. Ventilation Device, Energy Saving and Environmental Protection Device, Diecasting and forge Parts . Also included  the Equipments such as :Pneumatic Equipment, Hydraulic and Fluid Control Equipment, Robot and Peripheral Equipment.

And the Diecasting and Forge  mold & mould equipment such as :  Design and Manufacture Technology of Diecasting Mold, Mold Restoration Technology, foundry equipment, Melting Process and Casting Equipment. Molding and Core Making Equipment Ferrous and Special Casting Equipment. Dipping Equipment, Diecasting Machine and Auxiliary Equipment.

Furnace Materials, Device for Producing and Examining Heat Preservation. Drying Device, Furnace Instrument and Control System.Furnace Machine And Component, Furnace Materials, Fireproof Materials, Gas Device and Heating Material.

Diecasting and Forge

Ms Elwa Lee

Mobile/WhatsApp: 0086-15899675236

Tel: 0086-769-23190193

Fax: 0086-769-88705839

Email: Elwa@otaisteel.com

_{Our H13 STEEL -chapter 6}

_{The behavior of alloy carbides in steel is related to their own stability. In fact, the structure and stability of alloy carbides  of H13 are related to the electron deficiency of the d-electron shell and the S-electron shell of the corresponding C-forming elements [17]. As the electron deficiency decreases, the metal atomic radius decreases, the atomic radius ratio of carbon and metal elements increases, and the alloy C compounds change from interstitial phase to interstitial compound. The stability of H13 the C compound decreases, and its corresponding melting temperature and The lower the dissolution temperature in A, the absolute value of its free energy of generation decreases, and the corresponding hardness value decreases. VC carbides with face-centered cubic lattices have high stability. They begin to dissolve at about 900 ~ 950 ° C, and begin to dissolve in large quantities above 1100 ° C (dissolution end temperature is 1413 ° C) [17]; it is at 500 ~ 700 ° C. H13  precipitates during the tempering process, is not easy to grow up, and can be used as a strengthening phase in steel. M2C and MC carbides formed by medium carbide forming elements W and Mo have close-packed and simple hexagonal lattices, they are less stable, and they also have higher hardness, melting point, and melting temperature. They can still be used at 500 ~ A strengthening phase of steel is used in the 650 ° C range. M23C6 (such as Cr23C6, etc.) has a complex cubic lattice, worse stability, weaker bonding strength, lower melting point and melting temperature (dissolved in A at 1090 ℃), only after comprehensive alloying in a few heat-resistant steels Only have higher stability (such as (CrFeMoW) 23C6, can be used as a strengthening phase. M7C3 (such as Cr7C3, Fe4Cr3C3 or Fe2Cr5C3) with complex hexagonal structure) has worse stability. It is as easy to dissolve and precipitate as Fe3C type carbide , Has a large aggregation and growth rate, and generally cannot be used as a high-temperature strengthening phase [17].}

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Tel: +86-769-23190193

Fax: +86-769-88705839

Email: Jack@otaisteel.com