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4340 steel and 4140 steel

Otai exports various tool steel and alloy to more than 30 countries from Europe and America, Middle East and Asia. Our steel materials meet DIN / ASTM / EN / JIS etc different international standards. Today we will talk about 4340 steel and 4140 steel’s difference and its application.

4340 alloy structural steel belongs to gear steel.

It is used for important tempering parts that require good toughness, high strength, and large size, such as heavy machinery high-load shaft, turbine shaft with a diameter greater than 250mm, helicopter rotor shaft, turbojet engine turbo shaft, blade, high-load transmission parts, crankshaft fasteners.Gear, etc. It can also be used for rotor shaft and blade with an operating temperature over 400℃. It can also be used to make important parts with special performance requirements after nitriding treatment, which can be used for ultra-high strength steel after low-temperature tempering or isothermal quenching.

4140 steel, the steel has good workability, machining deformation of small, anti-fatigue performance is quite good.

On the hardenability of steel, 4140 heat treatment has good strength and good comprehensive mechanical properties, good manufacturability, high yield. The highest temperature is 427 degrees Celsius. 4140 strength, high hardenability, and good toughness, quenching deformation of small, high temperature creep rupture strength, and high. It is used for manufacturing forgings with higher strength and larger tempering cross section than 35CrMo steel, such as big gear for locomotive traction, supercharger drive gear, rear axle, connecting rod and spring clamp with great load, also can be used for drilling pipe joint and fishing tool of oil deep well below 2000m, and can be used for bending machine mold, etc.

Otai does not act as material handler. We possess proprietary technology and continuously iterates. We undertake every order to end and solve customer’s problems without any hesitation on responsibility. When customized special steel is hard to get, Otai settles satisfactorily completely.

4340 steel and 8620 steel

Otai exports various tool steel and alloy to more than 30 countries from Europe and America, Middle East, and Asia. Our steel materials meet DIN / ASTM / EN / JIS etc different international standards. Today we will talk about 4340 steel and 8620 steel’s difference and its application. 

4340 alloy structural steel belongs to gear steel.

It is used for important tempering parts that require good toughness, high strength, and large size. Such as heavy machinery high-load shaft, turbine shaft with a diameter greater than 250mm. It also used for making helicopter rotor shaft, turbojet engine turboshaft, blade, high-load transmission parts, crankshaft fasteners and etc. It can also be used for rotor shaft and blade with an operating temperature over 400℃. It can also be used to make important parts with special performance requirements after nitriding treatment. Which can be used for ultra-high-strength steel after low-temperature tempering or isothermal quenching.

8620 is the structural steel with the hardenability guaranteed by American standard, and the standard is as follows: ASTM A29/ A29m-2015 (hot forged and cold processed carbon steel and alloy steel bar).

It has high hardenability, no tempering brittleness, good weldability, little tendency to form cold crack, good maintainability, and cold strain plasticity. Generally used in quenching and tempering or carburizing state, used for manufacturing small and medium-sized automobiles, tractor engine, and gear in the transmission system. It also used in oil drilling and metallurgy open mine cone bit teeth and teeth body, manufacturing steam turbine gear whole rotor internal combustion engine connecting rod valve section forgings. At the same time, the surface of 8620 steel after carburizing heat treatment has relatively high hardness, wear-resistance and contact fatigue strength. While the core retains good toughness and can withstand high impact load. It can be used as automobile bearing, spindle, gear, mechanical parts, and other impact-resistant, wear-resistant workpieces.

Otai does not act as a material handler. We possess proprietary technology and continuously iterates. We undertake every order to end and solve customer’s problems without any hesitation on responsibility. When customized special steel is hard to get, Otai settles satisfactorily completely.

Since 2018, OTAI has increased the investment in 4140 prehardened plate, and now the daily inventory is kept at more than 800 tons. All regular size 12-180mm thickness plate is available to ship any time. The warehouse can start the delivery procedure immediately after ordering if not especially big volume. 4140 prehardened plate is 2000-2300mm wide and 3000-5800 long. It can be cut into the size required by customers. OTAI 4140 prehardened plate stock, can support 2-3 days quickly delivery.

Problems of 4140 prehardened plate in China market

First, both good and bad quality are in the market. Some supplier provide 42CrMo materials to replace the American Standard 4140. In fact, the chemical composition of the two materials is different. When foreign buyers receive the goods, the difference can be found by testing the composition. What OTAI provide is the real American Standard 4140.

Second, 4140 Prehardened plate require quenching and tempering process. Some heat treatment plant cannot control the temperature and hardness very well. It lead to the material mechanical properties not meet standard, and eventually there will be various problems in the end use. OTAI 4140 prehardened plate,is completely controlled according to the AISI Standard. All mechanical properties, including tensile strength, yield strength, elongation, shrinkage, impact energy and hardness, are tested and delivered only when they meet the standard completely.

Third, the delivery time is very long, even if the supplier promised a very short delivery time. In fact, they did not have so much inventory, and they had to transfer goods from other stockiest, agent or steel mills. In fact, few stockers can prepare all sizes all the time, and the size of out of stock will greatly extend the delivery time. Therefore, suppliers often say that 7-day delivery, in fact, they may not be able to deliver in one month, consider the long time sea transportation time, oversea buyers have missed the best sales opportunity.

Why OTAI can support quickly shipping time?

The 4140 plate is the core product of OTAI, with an average daily stock of more than 800 tons. If each dimension is lower than the limited inventory standard, it will be replenished in time to ensure that each thickness can be delivered at any time. Foreign customers often put together a container in multiple sizes. Other steel stockers need long time to gather the sizes together. However, it is very easy for OTAI to proceed such orders. For the hot-rolled black 4140 preharded plate, it takes 2-3 days to complete the shipping mark and pre delivery inspection, and then it can be delivered.

OTAI Customer Story

Half a year ago, one of our Argentina customer inquired about 4140 prehardened plate, black surface, without milling and cutting, and the thickness range is 30-100mm. This kind order is very simple for our company, and the price is very competitive as well, which is a very corresponding customer for us. The customer was satisfied with our price, asked how long the delivery time was, and I replied 2-3 days before delivery. But no further reply since then.

Eager to know why, I called my clients at night (during the day in Argentina). The customer said hat according to his previous experience, Chinese suppliers deliver goods within 30-45 days, and it is impossible to deliver goods to him within two or three days. He felt that the information I might tell lie to get his order, and then he worried about the quality and business safety with us. Although he was satisfied with the price, he still had to consider it. I learned about the customer’s concerns, and things became easier.

The next day, I went to the warehouse and took a lot of photos and videos of 4140 prehardened plate. I was in the video, show him our warehouse material, saw milling machine, cutting machine and inspection machine and test process. With these evidence, the customer dispelled all concerns, placed an order smoothly, and got the goods very quickly from us. Now this customer buy 4140 prehardened plate from us regularly.

Why choose OTAI?

For the 4140 prehardened plate, OTAI have obvious advantage compared with our competitors, because OTAI focuses on the 4140 plate, and there is no second one in China. Our company not only guarantees the complete size with sufficient stock, but also ensures that the chemical composition and all mechanical properties are 100% in line with AISI standard. If you want to purchase 4140 plate, OTAI is your rather good choice.

Tel: 0086-769-23190193

Fax: 0086-769-88705839

Email: jack@otaisteel.com

4140 plate Overseas Exclusive Agent on behalf of Otai Special Steel to sells 4140 plate outside of China . In 2020 , Otai Special Steel have big plan of 4140 plate . We keep daily inventory of 800 tons , and want to found our 4140 plate Overseas Exclusive Agent in every country or every regions outside of China .

We provide the best quality production and most competitive price . The fast delivery and the best supporting services . Hope that all the strength company and quality stockbrokers to join us . And start our win-win cooperation business relationships from here in today .

Why Otai Special Steel want to actualized 4140 plate Overseas Exclusive Agent out of China ? And Why we have this capability to achieve this project ?

1. Otai Special Steel have specialized in provide 4140 plate  . We have  export steel experience all over the world for more than 16 years . We have more than 100 repeat customer from Spain , Argentina , Chile , Ecuador , Brazil , Italy  , Ukraine , Qatar , Turkey , U.A.E , Egypt ,  Kuwait , Bulgaria , Japan , Thailand , Singapore , Malaysia , Vietnam … … . And all our steel have provided to the steel giants like Dyson Krupp, Mitsubishi … …
2. Otai Special Steel was the sole supplier of more than 800 tons 4140 plate of inventory in South China . From June , our dailly warehouse number may exceed 800 tons . Which size was sold out , we may replenish inventory accordingly . We will make sure any size any time have more stock list . I promise no other supplier could do this .
3. Excellent quality . BaoSteel makes the quality originals the best. And Otai Special Steel has our own quality inspection instrument. Hand-held spectrometer use on Chemical composition analysis per heat and conform to the standard . UT test to check the material inside quality. Hardness test to guarantee the requirement. Physical checking to ensure tolerance .
4. The best service from Otai Special Steel  ensure that . All the other difficult could be handle by Otai before shipment. The end-use guiding. Technical problems in the use of processing . Delivery problems. Shipping documents problems …… All the problems we could solve for you.

Tel: 0086-769-23190193

Fax: 0086-769-88705839

Email: jack@otaisteel.com

4140 steel and 8620 steel

Otai exports various tool steel and alloy to more than 30 countries from Europe and America, Middle East, and Asia. Our steel materials meet DIN / ASTM / EN / JIS etc different international standards. Today we will talk about 4140 steel and 8620 steel’s difference and its application. 

4140 steel, the steel has good workability, machining deformation of small, anti-fatigue performance is quite good.

On the hardenability of steel, 4140 heat treatment has good strength and good comprehensive mechanical properties, good manufacturability, high yield. The highest temperature is 427 degrees Celsius. 4140 strength, high hardenability, and good toughness, quenching deformation of small, high temperature creep rupture strength, and high. It is used for manufacturing forgings with higher strength and larger tempering cross-section than 35CrMo steel, such as big gear for locomotive traction, supercharger drive gear, rear axle, connecting rod and spring clamp with great load, also can be used for drilling pipe joint and fishing tool of oil deep well below 2000m, and can be used for bending machine mold, etc.

8620 is the structural steel with the hardenability guaranteed by American standard, and the standard is as follows: ASTM A29/ A29m-2015 (hot forged and cold processed carbon steel and alloy steel bar).

It has high hardenability, no tempering brittleness, good weldability, little tendency to form cold crack, good maintainability, and cold strain plasticity. Generally used in quenching and tempering or carburizing state, used for manufacturing small and medium-sized automobile, tractor engine and gear in the transmission system, oil drilling and metallurgy open mine cone bit teeth and teeth body, manufacturing steam turbine gear whole rotor internal combustion engine connecting rod valve section forgings. At the same time, the surface of 8620 steel after carburizing heat treatment has relatively high hardness, wear-resistance, and contact fatigue strength, while the core retains good toughness and can withstand high impact load. It can be used as automobile bearing, spindle, gear, mechanical parts, and other impact-resistant, wear-resistant workpieces.

Otai does not act as a material handler. We possess proprietary technology and continuously iterates. We undertake every order to end and solve customer’s problems without any hesitation on responsibility. When customized special steel is hard to get, Otai settles satisfactorily completely.

9310 steel and 8620 steel

Otai exports various tool steel and alloy to more than 30 countries from Europe and America, Middle East, and Asia. Our steel materials meet DIN / ASTM / EN / JIS etc different international standards. Today we will talk about 9310 steel and 8620 steel’s difference and its application.

9310 Alloy Steel (also known as AISI 9310 steel) is low alloy steel composed primarily of nickel and chromium.

The standard is ASTM A322. It shows high hardenability, high core hardness, and high fatigue strength. It also possesses solid ductility, weldability, and machinability properties. Its Components with a large cross-section requiring high toughness and core strength, It Mainly used for such as critical aircraft engine gears, automotive applications, structural components, gears, rods, heat-treatable shafts, high-performance helicopter transmission gears, and other components.

8620 is the structural steel with the hardenability guaranteed by American standard. Its standard is as follows: ASTM A29/ A29m-2015 (hot forged and cold processed carbon steel and alloy steel bar).

It has high hardenability, no tempering brittleness, good weldability, little tendency to form a cold crack, good maintainability, and cold strain plasticity. Generally used in quenching and tempering or carburizing state, used for manufacturing small and medium-sized automobile, tractor engine and gear in the transmission system, oil drilling and metallurgy open mine cone bit teeth and teeth body, manufacturing steam turbine gear whole rotor internal combustion engine connecting rod valve section forgings. At the same time, the surface of 8620 steel after carburizing heat treatment has relatively high hardness, wear-resistance, and contact fatigue strength, while the core retains good toughness and can withstand high impact load. It can be used as automobile bearing, spindle, gear, mechanical parts, and other impact-resistant, wear-resistant workpieces.

Otai does not act as a material handler. We possess proprietary technology and continuously iterates. We undertake every order to end and solve customer’s problems without any hesitation on responsibility. When customized special steel is hard to get, Otai settles satisfactorily completely.

9310 and Mild steel

Otai exports various 9310 and Mild steel to more than 30 countries from Europe and America, Middle East, and Asia. Our steel materials meet DIN / ASTM / EN / JIS etc different international standards. Today we will talk about 9310 and Mild steel’s difference and its application. 

9310 Alloy Steel (also known as AISI 9310 steel) is low alloy steel composed primarily of nickel and chromium.

The standard is ASTM A322. It shows high hardenability, high core hardness, and high fatigue strength. It also possesses solid ductility, weldability, and machinability properties. Its Components with a large cross-section requiring high toughness and core strength, It Mainly used for such as critical aircraft engine gears, automotive applications, structural components, gears, rods, heat-treatable shafts, high-performance helicopter transmission gears, and other components.

Mild steel is also known as mild steel because of its low strength and hardness.

It includes most ordinary carbon structural steel and a part of high-quality carbon structural steel, most of which are not used for engineering structural parts by heat treatment, some by carburizing and other heat treatment for mechanical parts requiring wear resistance.

The annealing structure of low carbon steel is ferrite and a small amount of pearlite. Therefore, its cold forming ability is good, can be used to roll, bend, stamping, and other methods of cold forming. The steel also has good weldability. The carbon content ranges from 0.10% to 0.30%. Low carbon steel is easy to be processed such as forging, welding, and cutting. It is often used to make chains, rivets, bolts, and shafts.

Otai does not act as a material handler. We possess proprietary technology and continuously iterates. We undertake every order to end and solve customer’s problems without any hesitation on responsibility. When customized special steel is hard to get, Otai settles satisfactorily completely.

4140 plate fast delivery  from Otai Special Steel in 7-10 days . Otai Special Steel was the sole supplier of more than 500 tons 4140 plate of inventory in South China . From June , our monthly warehouse number may exceed 500 tons . Which size was sold out , we may replenish inventory accordingly . We will make sure any size any time have more stock list . I promise no other supplier could do this .

Otai Special Steel have specialized in provide 4140 plate fast delivery . We have more than 16 years export experience . Also professional for 4140 / 8620 /4340 / 34CrNiMo6 / M2 / 18CrNiMo7-6 round bar … … . Our steel sold to all over the world . And our repeat customer from every where on the earth .

Why Otai Special steel could provide 4140 plate fast delivery in 7-10 days? And why so many repeat customer purchase 4140 plate from us. Why Dyson Krupp , Mitsubishi want to co-operate with Otai Special Steel?

1. Otai Special steel has adequate supply was first step to ensure 4140 plate fast delivery. All 4140 plate in warehouse comes from BaoSteel . Baosteel was the best steel mills in China. The quantities for 4140 plate in our warehouse arrived 500Tons, and from June, exceed to be more than 500Tons. All the sizes required by our customers are available in our warehouse.
2. Excellent quality was the second step for 4140 plate fast delivery. BaoSteel makes the quality originals the best. And Otai Special Steel has our own quality inspection instrument. Hand-held spectrometer use on Chemical composition analysis per heat and conform to the standard . UT test to check the material inside quality. Hardness test to guarantee the requirement. Physical checking to ensure tolerance . All the special size requested by the customer we have our own cutting machines. Vertical band sawing machine, Horizontal sawmill. CNC Gas Cutting Machine, Plane milling machine. End face milling machine, Large die spotting machine. Make sure the size meeting customer’s tolerance.
3. The best service from Otai Special Steel was the last step to confirm the 4140 plate fast delivery. All the other difficult could be handle by Otai before shipment. The end-use guiding. Technical problems in the use of processing . Delivery problems. Shipping documents problems …… All the problems we could solve for you.
4. Know all of the Otai Special Steel and 4140 plate. Any interesting, please contact us directly.

Tel: 0086-769-23190193

Fax: 0086-769-88705839

Email: jack@otaisteel.com

EN24 steel and mild steel

Otai exports various tool steel and alloy to more than 30 countries from Europe and America, Middle East, and Asia. Our steel materials meet DIN / ASTM / EN / JIS etc different international standards. Special Steel supplied by Otai is fully trusted by the US oil field giant and one military industry well-known enterprise. Today we will talk about EN24 steel and Mild steel’s difference and application.

EN24 steel is a kind of alloy structural steel – mechanical steel.

The first is to improve the hardenability of steel, to ensure that the steel after heat treatment to obtain a good comprehensive mechanical property, with high strength and enough toughness.

Suitable for cold pressing, thin blanking dies, punch and shear die. It is also suitable for manufacturing precision molds, precision instruments, precision side setting tools, reamer, milling cutter, roller, cold-drawn die, GAUGE, sample die, punch, cold-cut, scissors, tungsten knife, woodworking tools, spiral touch, various punching die and so on.

Mild steel is also known as mild steel because of its low strength and hardness.

It includes most ordinary carbon structural steel and a part of high-quality carbon structural steel, most of which are not used for engineering structural parts by heat treatment, some by carburizing and other heat treatment for mechanical parts requiring wear resistance.

The annealing structure of low carbon steel is ferrite and a small amount of pearlite. Therefore, its cold forming ability is good, can be used to roll, bend, stamping, and other methods of cold forming. The steel also has good weldability. The carbon content ranges from 0.10% to 0.30%. Low carbon steel is easy to be processed such as forging, welding, and cutting. It is often used to make chains, rivets, bolts, and shafts.

Otai undertakes every order to end and solve customer’s problems without any hesitation on responsibility. When customized special steel is hard to get, Otai settles satisfactorily completely.

34CrNiMo6 Round Bar with competitive price in June from Otai Special Steel . Otai Special Steel was sole supplier in South China for provide CrNiMo steel . Otai Special Steel have export steel experience all over the world for more than 16 years . We have more than 100 repeat customer from Spain , Argentina , Chile , Ecuador , Brazil , Italy , Qatar , Turkey , U.A.E , Egypt ,  Kuwait , Bulgaria , Japan , Thailand , Singapore , Malaysia , Vietnam … … . And all our steel have provided to the steel giants like Dyson Krupp , Mitsubishi … …

Otai Special Steel have the complete 34CrNiMo6 Round bar stock list . Any size any condition could be found here . Although we have many stock list and many size to be choose . The price was very competitive .

Why so many customers were Otai special Steel’s repeat customer . We have our own advantage as follow :

1. Sufficient supplies. Other suppliers may have carbon steel, alloy steel, but no one has CrNiMo steel. Otai Special steel has 34CrNiMo6 round bar, 18CrNiMo7-6 round bar, 8620 round bar, tubes, 4340 round bar, 30CrNiMo8 … … All normal sizes have a stock list, special size could place the order .
2. Best quality. All the materials from the mill factory to our warehouse have qualified. Otai Special steel has professional measurement tools. Handheld spectrometer to check Chemical composition analysis. UT test to check the material inside quality. Hardness test to guarantee the requirement. Physical checking to ensure tolerance .
3. Competitive price. As we know all this kind of steel market situation, so we could give the best price for you.
4. Good service. We could provide the steel as the customer requested. And we also could give customer suggestions to save costs, choose the correct materials. And give professional technical guidance.                                                                                           
5. Otai Special Steel no only provides steel 34CrNiMo6 round bar. But also provide the best service all according to this steel. Any inquiries, please contact us directly.

Tel: 0086-769-23190193

Fax: 0086-769-88705839

Email: jack@otaisteel.com