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As Chinese Lunar Year coming soon ,we got the feedback from our customer who order 4140 Round Bar Hot Rolled Alloy Steel from us that they need to delay their import process ,and let us help to ” Freetime extention ” of containers shipment .

4140 Round Bar Hot Rolled Steel shipment

We got the news from our customer 2 days ago as follow :

Dear Elwa : MSC  local agent received confirmation from that  free time appears here only  7 days . Please contact your installer agent for free time extension in China.

Some of manufacture industry starting holiday from Jan,2020 (about 20-30 days holiday ) during spring festival .The shipment company and vessel company also start to arrange the holiday schedule .

We  inform to all of customer that please do the import custom process on time ,especially during Chinese Spring festvial .Time is money ,there is not need to pay more other fee for local fee or demurrage because of the import process delay .

Because all extention process of the demurrange / Storage free day will stop during holiday , there is nobody to handle those specail request while on holiday.

Ms Elwa Lee

Mobile/WhatsApp: 0086-15899675236

Tel: 0086-769-23190193

Fax: 0086-769-88705839

Email: Elwa@otaisteel.com

4140 plate hot rolled, Otai has storage over 500 tons daily, if you have the demand, please feel free connect with us, the delivery time is very short, once you place an order, you will repeat again。

Time flies, this is the third month I worked at Otai special steel company. From the first day I came to Otai, I heard a lot about the 4140  steel.This is one of the best-seller product of our company, not only my boss but also my colleagues, love the 4140 steel very much, do you know the reason? because 4140 is popular by many customers,otai provides high quality 4140 steel, our 4140 is produced by china’s famous mills such as baogang steel, wugang steel.

Maybe you do not know much about the 4140 plate hot rolled, I ‘m glad to share the information with you.

4140 steel is common chromium-molybdenum steel that usually used after quenched and tempered, with high intensity, high hardenability. It has good workability, slight processing deformation, fatigue resistance is quite good, is a medium and so on hardenable steel.

4140 is used to manufacture forgings that require higher strength ,and larger quenched and tempered section. such as large gears for locomotive traction, supercharger transmission gears, rear axles, heavily loaded connecting rods and spring clips.

4140 is also used to Petroleum deep well drills pipe joints ,and fishing tools below 2000m and can be used in the mold of the bending machine.

What’s the meaning of hot rolled?

it’s a method of manufacture steel. Hot-rolling refers to a mill process in which you roll the steel at a temperature above its recrystallization temperature; a heat that typically exceeds 1000° F.

hot-rolled steel most suitable for structural components ,and other applications where incredibly precise shapes, and tolerances are of less importance.

4140 plate hot rolled, Otai has storage over 500 tons daily, if you have the demand, please feel free connect with us, the delivery time is very short, once you place an order, you will repeat again.

Mr Jack Tan

Tel: 0086-769-23190193

Fax: 0086-769-88705839

Email: jack@otaisteel.com

OTAI Steel focus on alloy steel business more than 20 years, become one of leading special steel stock holder in South of China step by step. Steel 4140 | 42CD4 plate hot rolled become our key product. We keep daily stock 500 tons, black surface plate can support immediately shipment after order confirmed, and milled plate can proceed per customer’s requirement. OTAI have 10 band saw and milling machine, cut to different size and milling precision requirement per different customer. 4140 | 42CD4 alloy steel material is a high quality Quenched and Tempered Alloy Structural steel, It belong to the high quality medium carbon alloy steel, Oil Quenched & Tempered Hardenss is 28-34 HRC.4140 | 42CD4 Annealing delivery hardenss less than 250HB.

In this article let’s introduce 4140 |42CD4 plate hot rolled supply information

4140 |42CD4 plate hot rolled dimension

1) Steel Plate:

Thickness 12-120mm

Width 2000-2300mm

Length 3000-5800mm

2) Flat Bar

Thickness 12-120mm

Width 200-1000mm

Length: 2000-2300mm

3) Fixed Size

Per customer’s requirement

 4140 |42CD4 plate hot rolled delivery condition

1) Black surface as rolled
2) Milled plate per different milling precision requirement

4140 |42CD4 plate hot rolled heat treatment in our stock

1) Without any heat treatment
2) Annealed
3) Quenched and tempered (Q+T)

4140 |42CD4 plate hot rolled delivery time

1) Black big steel plate: Available in stock, immediately shipment

2) Flat bars cut per need: 3-7 days

3) Milled plate per need: 3-7 days

4) Lead time for Q+T: 10-15 days

If any special dimension and other technique specification requirement, please contact us for detail discussion. OTAI Steel are professional and competitive enough for 4140 |42CD4 plate

OTAI 4140 |42CD4 plate hot rolled steel is directly from top 3 China mill, quality is good and stable, price is competitive. This March, OTAI Steel will increase the daily stock to 800 tons.

New year, new opportunity. Let’s work together.

Tel: 0086-769-23190193

Fax: 0086-769-88705839

Email: jack@otaisteel.com

I talked about Cr12MoV with my  friends, and a friend said that it was “junk material”

I talked about Cr12MoV with my  friends, and a friend said that it was “junk material”!

I did not agree with. Cr12MoV has five benefits at least in my mind. The first one,the hardness  is 58-60 HRC， High hardness represents high wear resistance. When heat treated, the hardenability is good, heat treatment deformation is small, the risk of cracking is reduced, and the ratio of carbon is Cr12 is low, and Cr12MoV crack resistance is better than Cr12. For many applications that require wear resistance, Cr12MoV is good for it. The fourth one has a lower price and can reduce the cost of mold making greatly. The fifth one has a wide range of uses. All Cr12MoV can be used for extrusions dies, cold extrusion dies for common requirements, circuit board dies, and parts that require wear resistance. It is such a good material.

I always believe that there no the best materials in the world,but the most suitable does.

Cr12MoV Tool Steel Chemical composition

Mechanical properties:
Hardness: annealing, 255 ～ 207HB (14-25BRC), indentation diameter 3.8 ～ 4.2mm; quenching, ≥60HRC

Cr12MoV uses
Cr12MoV mold steel has higher hardenability, hardness, strength and toughness after quenching and tempering than CR12. Workpieces with a diameter of 300 ~ 400mm can be fully hardened, and the quenching deformation is small, but the plasticity at high temperature is poor. Cr12MoV is mostly used to make compound molds and tools with large cross sections, complex shapes, and heavy workloads. Such as punching die, trimming die, piping die, steel plate and so on.
Heat treatment specifications
Heat treatment specifications: 1. Quenching, oil cooling at 950 ～ 1000 ℃; 2. Quenching at 1020 ℃, tempering at 200 ℃ for 2h.
Metallographic structure: fine granular pearlite + carbide.
Delivery status: The steel is delivered in annealed condition.
Specification for softening of cold extruded blanks
Use iron dust protection for heating, temperature 760 ~ 780 ° C, time 10h, furnace cooling, hardness 96bw, can realize cold extrusion smoothly

Ms Sharon Wan

Mobile/WhatsApp: 0086-13580960968

Tel: 0086-769-23190193

Fax: 0086-769-88705839

Email: Sharon@otaisteel.com

Din 1.2344, otai with over 20 years pre-sales and after-sales experience.

Recently, I am careful about the news of middle east, because we have a customer from middle east who bought the din 1.2344, I heard that one of middle east country’s situation is serious, the news shows US and one middle east country on the brink of war, thousands mourn soleimani vow revenge to America, I am shocked with the news, the people in that country are upset with about the safety, our customer is forced to other countries to keep safe.

I hope the situation will change better, the war is terrible, no one benefits from the war. Only the safety is assured, will the country have a prosperous future, and people live a happy life. Our customer in one middle east bought the din 1.2344 for hot forging dies, he believes the quality of our din1.2344.

Din 1.2344 consists of chromium, molybdenum, and vanadium and is known for its high hardenability and great toughness. Otai Special Steel could supplier of 1.2344 Hot Tool Steel in round bar, plate, flat bar, sheet, square and block, the measure should be regular standard. Special sizes could be custom-made.

Its main characteristics are as below:

(1) has high hardenability and high toughness;

(2) Excellent resistance to thermal cracking, which can be water-cooled in the workplace;

(3) It has medium abrasion resistance, and can also be used to improve the surface hardness of carburizing or nitriding process, but slightly reduce the resistance to thermal cracking;

(4) Because of its low carbon content, the secondary hardening ability in tempering is poor;

(5) It has softening resistance at higher temperatures, but the hardness is higher than 540 °C (1000 °F), and the hardness is rapidly decreased (ie, the working temperature is 540 °C);

(6) The deformation of the heat treatment is small;

(7) medium and high machinability;

(8) Medium resistance to decarburization.

Din 1.2344  steel is the most widely used and most representative hot work die steel.Even more noteworthy is that it can also be used to make important components in the aerospace industry.

Mr Jack Tan

Tel: 0086-769-23190193

Fax: 0086-769-88705839

Email: jack@otaisteel.com

A new customer asked me which country bought low carbon steel from us before,I have no idea about the point of this question.

A new customer asked me which country bought low carbon steel from us before,I have no idea about the point of this question,but we did sale a lot of 1020 round bar and low carbon steel pipe to some counties.most of them are from South America.Such as Chile, Mexico, Argentina.And 80% reorder of 1020 low carbon steel pipe every 2 month.After offering quotation,he said our price was to high,someone offer him a cheaper price,I asked how much lower.he told me $150/ton around.I told him that the price was not make sense at all,I am sure he will never get the steel .

After afew month,he contact me again,he sent the same inquiry to me,I asked him why disappear last time?he told me that after he finished the payment,he never catch the company anymore,and this time,he is very careful,not only care about the unit price anymore,he ask me to send sample.I did not send him sample,I told him,it’s very easy to buy a sample in Chinese market,after that,I show him our stock picture and I,and share the loading pictures and BL copy.

Finally ,he got the low carbon steel pipe,by paying the second time.and he told me he will never change supplier,we made him feel save.

If you want to know more about low carbon steel,please click the link or see as below

AISI 1020 Steel is a mild carbon steel, 1020 steel belong to the high quality low carbon steel, cold extrusion, carburizing and hardening steel. The low steel strength, toughness, plasticity and weldability are good. Tensile strength of 253-500 mpa, the elongation is 24% or higher.

Chemical composition

Equivalent Of 1.1151 Carbon Steel | Flat Steel Bar

Ms Sharon Wan

Mobile/WhatsApp: 0086-13580960968

Tel: 0086-769-23190193

Fax: 0086-769-88705839

Email: Sharon@otaisteel.com

h13-die steel application –chapter 10

H13  -heat treatment are decarburization, superheating, And H13  also make the mold surface gets residual tensile stress. That H13 will make the mold get failure early. If the temperature of some parts of grinding surface up to over 800℃, and not make it cool fully. Then the material of the surface layer of  H13 will be re-austenize.

1. And quenching into martensite. So H13 the surface layer of the die will get high stress. At the same time,H13 will make the possibility of getting grinding crack be higher. The technology of heat treatment .
2. Taking the heat treatment in the right way will make the mold get what it needs about the properties and raise the time of working. But if do H13 in the wrong way, H13 will cause the defects of heat treatment. H13 will harm hugely to its load capacity. The defects of H13 will be dehiscence, strength is not enough and etc.
3. After a period of time of use, the internal stress accumulates to a damage level. H13  must do a work of strain relief tempering. If not, H13  will dehiscence during work time.

The use and care of h13-die steel

The preheat of steel moldH13 steel has high content alloy elements and its thermal conductivity is bad. So it must fully preheat before the use. The temperature of preheating too high, then the temperature of the mold will be higher during the work. And its strength will get down, it will easy to get plastic deformation then make the surface subsides. However, if the temperature of the preheating is too low, the temperature of the surface has a big change. With high heat stress, get the crackle is more easily. The temperature of preheating for H13 steel mold is at the range of 250-300℃.

That can reduce the temperature difference between the mold and the forgeable piece to avoid excessive thermal stress on the surface of the mold, and effectively avoid the plastic deformation of the mold surface.

WhatsApp: +86-769-23190193

Tel: +86-769-23190193

Fax: +86-769-88705839

Email: Jack@otaisteel.com

The Bright High Speed Steel M2 is known for its balanced combination of abrasion resistance, toughness and good red hardness. it is a tungsten-molybdenum high speed tool steel, m2 tool steel is used in a variety of applications and worldwide. M2 tool steel is the most popular high speed steel because of its superior qualities. As a result of its low carbon content, M2 tool steel high speed tool steel has an outstanding combination of toughness properties and abrasion resistance when correctly hardened and tempered.

M2 tool steel equivalent with JIS SKH51, SKH9, DIN WN-r 1.3343, GB W6Mo5Cr4V2 .

Today i have received a new inquiry from my client , he request for the Bright High Speed Steel M2 Round bar . The client was a wholesaler have business in Serbia, also their activities are in industrial spare parts like machine spare parts, Cutting and Grinding wheels, ball Bearing, Roller chains, Twist drill bits, hand and Machines TAPS AND DIE, Hoists and Cranes, screwdriver Bits, Crown wheel and pinion for passenger car and Gundrills/Masonry drill bits and etc… .

They would like purchase Bright High Speed Steel M2 with high quality round bars or raw materials that suitable for Twist Drill Bits DIN 338 HSS/HSS Co5%/HSS Co8% sizes of 1.0 mm to 20 mm .

And after communicate with customers , we found that he did not need Bright High Speed Steel M2 . Also the M42 have Cobalt 7.75-8.75 , M35 have Cobalt 4.6-5.0 did not meeting his requirement of Cobalt less than 5% . Which he needed was High Speed Steel 1.3243 . The standards should be W-Nr. German rules .

Tel: 0086-769-23190193

Fax: 0086-769-88705839

Email: jack@otaisteel.com

42CrMo4 material is the Germany standard, another number is 1.7225. In American standard, it is AISI 4140 or SAE 4140.

We met some overseas customers who purchase the 42CrMo4 material very frequently from us afterwards. They asked us the question before, compared the steel mill, what is your company’s advantages?

We are the professional stockist including the tooling steel, high speed steel, alloy steel and carbon steel for more than 20 years.We have our own warehouse for stocking the different steel material, like the 42CrMo4 material.

As we have our machine equipments, such as CNC flame cutting , horizontal and vertical saw cutting machine, Grinding and Milling machine. Therefore, we could make the different machining as the customer’s special request. However, the factory mills are difficult on supporting it by tailor-made.

For making sure and testing the quality, we have Chemical Spectrometer, Ultrasonic Tester and hardness tester.
We could support the customer in lower MOQ, say 2-3Tons for each size.But from the mill, the MOQ is very huge. Usually in the mill, the MOQ for each size is ranged in 30 to 50Tons.

What’s more, we could make the more flexible payment terms as customers’ request. For example T/T, D/A,D/P, L/C, Western Union, MoneyGram. But for the Mills, they only accept the payment terms in 100% pay in advance.
At last, for the packing way, we could fulfill different customers’ request accordingly. But the mills will follow their own packing way by company’s policy.

Now for supporting and fulfilling the customers’ request, our company stocked many steel plates for the running 42CrMo4 material. For this 42CrMo4 material we would like to special highlight on this. It is produced by the only imported advanced steel making equipment. Moreover, the quality is approved by Uddeholm and certificated by the 3rd party SGS. Most of the customers often place the 42CrMo4 material repeat order to us because of the guaranteed quality, competitive price and fast delivery time.

Tel: 0086-769-23190193

Fax: 0086-769-88705839

Email: jack@otaisteel.com

H13 application –Chapter 9

• The design of the H13 die steel

The design of mold depends on the shapes and specifications of products to make sure the size of the die for H13. H13 die steel was good for the strength of die in tooling steel.

Furthermore, too small a radius of a rounded corner, ill-suited groove position and etc will make the die gets big pressure during the heat treatment. H13  is easy to cause crackle. So H13 must make the taper angle, hole and etc at the right position in the mold.

• Production technique-H13

1. Forging ProcessThere are so many alloy elements in H13 steel. The resistance of deformation is big at the time of forging. And the thermal conductivity of the material is bad. So the eutectic temperature is low.  H13  is easy to burn. So the preheated temperature range must be at 800-900℃. Then heated to the initial forging temperature of 1065-1175℃. In order to crush large non-metallic inclusions and make the carbide get small, the forging ratio needs to be bigger than four. At the cooling process after forging, it is possible to get quenching crack. And the core is easy to get transverse cracks. So H13 steel must be slowly cooled after the forging.  The machining of cutting The roughness of the surface of H13  after the machining of cutting, H13has a large impact on the thermal fatigue property of steel mold. The roughness of the steel mold surface of H13 must be lower. The knife mark and cullet cut are not supposed at here. Those shortages will cause pressure over control to make the thermal fatigue crack. So, must pay attention to handle these things in the mold at the time of processing. 3. The machining of grinding At the process of grinding, the generation of heat by friction at the parts which is easy to cause the problems of crack, pyrosis and etc.

WhatsApp: +86-769-23190193

Tel: +86-769-23190193

Fax: +86-769-88705839

Email: Jack@otaisteel.com