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The invention patent of Pre-treating agent we just achieved is based on Zr, Al, Ca, Ba, Y as the main elements of the Fe-Si alloy, these elements and liquid iron sulfur, oxygen, nitrogen and other stable compounds, the density of these compounds and liquid iron density is close, easy to disperse in the liquid iron, is very suitable for graphite heterogeneous nucleation particle.And in the process of molten iron smelting, even at a higher melting temperature, decomposition will not occur, which ensures the graphite nucleation particle has a strong stability. The benefits of the invention are as follows: remarkable pre-treatment effect, Strong anti-decay ability, and stability and consistency of the performance of molten iron are guaranteed; The agent can be applied in gray cast iron, ductile cast iron, vermicular cast iron casting production process; which can effectively purify molten iron, de-oxidation, de-sulfurization, denitrification effect; Reduce the super cooling degree of molten iron, improve the metallurgical conditions of molten iron, and increase the amount of graphite in cast iron;Reduce the casting white mouth tendency, Thus to get good casting section uniformity; Improvement of the mechanical properties and outstanding stability. of the Cast iron products.

The range of chemical composition of high speed steel roll is very wide in national standard, such as Cr is 3.00-8.00, Mo is 2.0-8.00, V is 2.00-9.00, W is 0.00-8.00. The manufacturing costs of Mo and V containing 2%~3% of the chemical composition are different from of the rolls containing 7% and 8% of the Mo and V, and the manufacturing costs of the rolls with the same chemical composition except W are big different. This is the reason why there is a big gap in the sales price of high-speed steel roll produced by different roll manufacturing enterprises. Similarly, there is a big gap between the performance and use effect of the product. The comprehensive performance and application effect of the roll depend on the texture of the roll, and the texture of the rolls depends not only on the heat treatment control of the roll, but also on the composition control of the roll and the content of the alloy elements We are committed to supplying high quality HSS rolls. any inquiry, feel free to contact with myron.zhu@bkdrtech.com

Dear Firends We have resumed work from our new year holiday, I wish you every happiness and prosperity in your new year 2021. Any inquiry for mill rolls, feel free to contact with myron.zhu@bkdrtech.com. We will supply best quality rolls with lower price.

German industrial giant thyssenkrupp said on May 12 that its second-quarter net loss more than quadrupled to 948 million euros ($1.02 billion) in the year to the end of march, as the coronavirus outbreak hit all of its business lines, from steel to submarines. Separately, the group forecast that the third-quarter loss could widen further to 1 billion euros Thyssenkrupp group management is currently in talks with representatives of other steelmakers about the sale of the steel unit, according to German media sources within the group and the industry.Interested investors include China's BaoWusteel, Sweden Steel AB and the European arm of India's tata, after thyssenkrupp sought to merge with tata Steel Europe but was blocked by eu antitrust authorities.Thyssenkrupp is still not giving up on plans to merge with tata steel Europe, according to insiders, as the group has long argued that the European steel industry needs consolidation. The state of negotiations in thyssenkrupp's steel division has been closely watched and discussed within IG Metall, a trade union.The union, like the company's internal management committee, is worried that the steel sector will be sold off abroad.Both baosteel and SSAB want majority stakes, and tata steel should feel the same way, according to a person familiar with the matter. IG Metall, on the other hand, prefers the merger of thyssenkrupp steel, the Saarhutten association (the professional and employers' association of the steel industry in the saarland state of Germany) and Salzgitter.There were also earlier reports that thyssenkrupp's steel unit would merge with rival salzgeet, which were denied by both sides.Thyssenkrupp has yet to make a final decision We supply high quality rolls to many European steel plants, any inquiry, feel free to contact with myron.zhu@bkdrtech.com

Compared with ordinary centrifugal cast high speed steel rollers, the CPC method has the following characteristics: The molten metal solidifies from the bottom up, which is conducive to the filling of liquid metal.Because there is no density segregation in the special casting method, high carbon, high tungsten and high vanadium high speed steel can be used for the outer layer of the roller, which has good red hardness and high temperature wear resistance.The outer layer of the roll solidifies in a water-cooled crystallizer to obtain fine solidification structure and improve the strength and toughness of the roll and thermal fatigue resistance.The forging steel is used as the core material, which has high strength, the core is not in danger of breaking, and the bending load of the roll is increased, so that the rolled steel plate has a better shape.The wide range of material selection and high bonding strength of the inner and outer layers of the roller make it possible to produce materials that could not be produced by centrifugal casting method before, such as supereutectic materials and particle reinforced high speed steel matrix composites.The transition layer between the outer layer and the core is well bonded by metal diffusion. The outer layer of the composite roller has a large residual compressive stress, which can prevent the cracks on the surface of the roll from infiltrating into the core and causing the roll to peel off.CPC process can be used not only to prepare new rollers, but also to repair old ones. The cost of CPC equipement is higher and production efficiency is lower that centrifugal method. We are committed to supplying high quality HSS rolls. any inquiry, feel free to contact with myron.zhu@bkdrtech.com

The main problem when using HSS Roll are as below: First, the surface of the roll is easy to produce oxidation, crack, peeling and other defects.The roll with different chemical composition and metallographic structure should be selected according to different mill stand and rolling environment.The cooling condition of high speed steel roll is stronger than that of high chromium cast iron roll.The cooling water should be as sufficient as possible. It is advisable to replace the original tapered nozzle with a flat nozzle, and use 3/4 cooling water for cooling on the side of the steel outlet of the roll. The surface temperature of the roll should be controlled below 50℃.In addition, the cooling water in the middle of the roll body should double the cooling water at the side of the roll, Some steel plant even increase the cooling water by 40%~60%, so steel rolling manufacturers should consider the cooling water before using high-speed steel roll Second, the friction coefficient between the roll and the rolling material increases.The friction coefficient between the high speed steel roll and the rolled material is large, the rolling load increases, and it is easy to slip, adopt Oil lubrication, strip surface cooling, reducing the blank temperature to reduce the friction coefficient. In addition, optimizing the composition of high speed steel roll is also an effective way to reduce the friction coefficient. Third, roll damage caused by steel rolling accident.High speed steel material has low impact toughness, high brittleness and weak anti-accident performance. Therefore, it is necessary to strengthen management to ensure the normal operation of the mill and reduce the damage caused by rolling accidents. We are committed to supplying high quality HSS rolls. any inquiry, feel free to contact with myron.zhu@bkdrtech.com

The thermal expansion of HSS material is large, and the uneven roll temperature distribution is easy to produce uneven thermal expansion and abnormal oxide film fall off, which affect the thermal crown and roll gap precision.The key factor affecting the oxidation film and thermal crown of high speed steel roll is the roll surface temperature. Therefore, the good cooling system will shorten the cooling time of roll surface from the high temperature which are important to control the oxide film thickness of the roll surface, reduce the thermal crack. During the hot rolling process, the instantaneous contact temperature of the roll is 600℃~750℃, and the temperature of the roll body exceeds 50℃. After the roll surface comes out of the contact arc, the temperature must be reduced from 700℃ to below 300℃ as soon as possible to prevent further oxidation.After the roller passes through the instantaneous high temperature contact zone, the rapid operation in the 100% water-cooled environment is conducive to the formation of Fe3O4 oxide film with the best protection performance.The cooling effect of the roll can be enhanced by increasing the cooling water at the outlet side, reducing the cooling water at the inlet side and reducing the height of the water cutting plate. By optimizing the distribution of roll cooling water and increasing the cooling water in the middle of the roll, the temperature of the roll surface can be significantly reduced and the temperature distribution uniformity can be improved We are committed to supplying high quality HSS rolls. any inquiry, feel free to contact with myron.zhu@bkdrtech.com

When the work layer is thin or the work layer contains large quantity precious metals. We produce rolls by centrifugal method with two or three different materials, the work layer is wearable and heat resistant while the core with good mechanical resistance. There are two different casting method of centrifugal casting, horizontal and vertical cast. The main method produce centrifugal rolls is horizontal method, When the diameter length ratio is higher, we prefer to vertical casting method. Any inquiry, feel free to contact with myron.zhu@bkdrtech.com

Be full confident of the Medical scientists and the doctors, we are sure to conquer the virus ASAP!!!

Thanks for everyone around the world who are concern about the Coronavirus spreading in China. As a Chinese, a Chinese mother, i truly saw the powerful ability of our motherland how she struggle for the virus to protect us. This is another test for China and the world community after SARS. At this moment, any slamming, taunting, fanning, and gloating are all manifestations of lack of humanity. The virus does not recognize the country, nation, race, rich or poor. There is no difference in virus transmission. China's powerful system and the effective measures it has taken to prevent and control novel coronavirus-related pneumonia are rarely seen in the world, Director-General of the United Nations' World Health Organization Tedros Adhanom Ghebreyesus said last Tuesday. The WHO and the international community highly appreciates, and fully affirms the decisive measures the Chinese government has taken to deal with the outbreak and also thank China for its tremendous efforts to curb the spread of the contagion, he said. China set a record in identifying the pathogen in a short time following the outbreak of the contagious disease, Ghebreyesus said, and he praised the country's timely sharing of the virus' DNA information with the WHO and other countries. In response to the GVM's call, the school has delayed the start of school, and most companies have extended the Spring Festival holiday. This is not a sign of lack of confidence in controlling the virus, it is one of the measures to put people's lives first. Everyone knows that this is the most effective way to control the spread of the virus. I went to supermarkets, fruit shops, etc., and there was no snap-up like it was fabricated by some media. Prices have not skyrocketed. The price department is also strictly controlling the prices of daily necessities to protect people's daily lives. Relevant departments have made the unified deployment of some protective supplies such as masks to ensure timely and adequate supply. And Till now, lots of hositals have been built within the past 10 days to accommodate and cure more patients. Which country can make such an appropriate response in the first place? I am grateful for living in such a great country. I believe that our Chinese people will be able to eliminate the disease asap. Because we eliminated more severe SARS than this time in 2003, didn't we? Welcome to struggle with us. Contact me via alley.wang@bkdrtech.com if you have any inquiry or anything you`d like to learn.

The 14th International Foundry Trade Fair With Technical Forum is coming, warmly welcome you to visit us at Booth No. 16/C01-04. The Messe Düsseldorf and GIFA have been reflecting technological highlights for decades. Innovations in casting technology are traditionally the focus of the world`s leading foundry exhibition. We, Shijiazhuang BKDR Metallurgical Materials Co., Ltd as the professional manufacturer of metallic additions, mill rolls and wear parts, has been offering a wide range of products, services and customized total solution to Foundry, Steel-Making and Mining around the world. Sincerely welcome you to visit us, For more info. , please contact alley.wang@bkdrtech.com.

According to rolling mill operation and their own problems, choose a reasonable material for roll. Ensure, the implementation of the normal change slot system for rolls. The normal cycle of change slot for rolls determine by the damage manner and timing. Those are based on roll wear and the quality of rolled piece, combined with rolls or rolling tonnage mileage in a planned replacement of the rolls or exchange the slot. The various mill accident, roll to a certain degree of damage and the impact, should change slot or rolls in time. In the analysis of avoiding damage to these forms, referred to the improper operation of the rolling and the improper use of the phenomenon of rolls. When repair module of roll and lathe, you must be fully eliminate body surface defects. Establish a strict record of the detailed operation of rolling, recording repair and grind records. When Failure phenomena of rolls occurred, truly analysis, find the best way to solutions failure of rolls.

Now, two sides of supply and demand is a partnership of common development. The whole process of the use roll including maintenance techniques, the use of technology and technical services, which were got more and more attention in the supply and demand sides. Rolls use side should be provided for all rolls data for supply sides(water pressure, water, water temperature, Tap cooling form, rolling time and rolling tonnage, for roll-for-slot system, Single-off the amount of steel, with a total rolling volume, the user is using the failure occurred roll form, etc.). Roll suppliers, roller in the development of specific varieties of the program production process, it is important to combine specific mill working conditions (water quality) and rolled products, combined with other users before the success of the same material the use of mill experience, determine the best materials and processes production to meet on the roll with the use of performance requirements. According to the failure of rolls occurred, it is just supply and demand in close cooperation and common analysis of the form rolls and the reasons for the failure, according to the analysis of objective reasons, to take targeted measures to ensure good use of effects and life expectancy.

Slurry pump selection in the production practice of coal separating plant, slurry pump is not only widely used for black water, circulating water, coal slurry and heavy media suspension and other fluid transport operations, and when used as a graded concentrate cyclone, heavy medium (water) Sorting cyclone, feed pump of filter press, it also directly affect the process indicators. Therefore, as an important auxiliary coal separating plant, its operation directly affects the normal operation of the production system. ZJ series slurry pump and AH, ST series slurry pump are widely used in coal separating plant, ZJ series slurry pump is China's self-developed products, AH, ST series slurry pump is technology introduction from Warman pump.

The assembly precision of CMZ slurry pump internal components must be in accordance with the standards, including the impeller, seal and bearing; in the transport process, will inevitably cause the internal components of slurry pump loose, therefore, the pump is mounted to the base, to find it leveling. The outlet and entrance of the slurry pump are connected and the stress will be produced after the pipe is broken. If the alignment is not good, it is easy to cause radial movement, shaft vibration and shaft deviation in the operation, so that the power consumption increases, the bearing and sealing wear, and shorten the service life. In order to improve the suction performance of slurry pump, the suction line should be as short as possible to minimize the bend pipe pump (preferably with large curvature radius elbow), in order to reduce the resistance loss of pipeline. In order to prevent the pump from cavitation, the pump suction line should be as much as possible to avoid accumulation of gas bladder shaped parts, can not be avoided, should be located in the sac shaped exhaust valve. When the suction pipe of the pump is vertical, if the suction pipe is equipped with a reducer, it should be equipped with eccentric reducer, so as not to form the airbag

The quality factor and safety factor of the slurry pump is particularly important, but the daily maintenance is also very important. 1) Bearing water pressure, water volume have to meet the requirements, at any time to adjust (or replace) the tightness of the filler, do not cause shaft seal leakage. And replace the sleeve timely. 2) When replace the bearing, be sure to ensure that the bearing components inside without dust, lubrication oil is clean , during pump running, generally the bearing temperature less than 60- 650C is appropriate, the maximum bearing temperature does not exceed 750C. 3) To ensure that the motor and pump coaxial, to ensure that the elastic pad in coupling is complete and correct, it should be replaced timely after damage. 4) Ensure that pump components and piping systems are installed correctly, securely and reliably. 5) Part of the slurry pump parts are vulnerable parts, pay attention to the loss of wearing parts in daily use, keep its maintenance or replacement in time. During the process of maintenance or replacement of wearing parts, ensure that the assembly is correct, the gap adjustment is reasonable, to avoid the emergence of tight friction phenomenon. 6) slurry pump suction piping system must be no leakage, at the same time, we should pay attention to whether the suction mouth was blocked or not in the operation. The medium treated by slurry pump usually has solid particles, the filter placed in front of the slurry pump must control the size solid particles which can ensure pass through the slurry pump, reduce the possibility of the large particles or long fiber material go into the pump and cause congestion. When Slurry pump start to work, the pump needs to be mounted on the land, the water pipe was putted in the water, also need to irrigation pump before commencement. due to structural constraints for mud pump and Submersible Slurry Pump, the motor need to be placed on the water above, and put the pump into the water, it must be fixed, otherwise, if the motor fall into the water, then cause the motor to be scrapped. And because the length of the long axis is generally fixed, the pump installation has more trouble, the application of the occasion has a lot of restrictions.

GMZ slurry pump mechanical seal failure mainly for the following three reasons: (1) the sealing surface is opened In the repair of mechanical seals, 85% of the sealing failure is not caused by wear and tear, but before wear, it has leaked. When the sealing cover is opened, the solid particles in the medium under the action of liquid pressure into the sealing surface, the sealing surface is closed, the solid particles embedded soft ring (usually the right ink ring) on the surface of it into a "wheel" will damage the hard surface. Because the ring or rubber ring fastening on the shaft (sleeve), when moving, moving ring can not be fit, and the sealing surface and sealing surface of the open, closed backward into the sealing surface, made of solid particles in. At the same time, there are solid particles between the shaft (shaft sleeve) and the sliding parts, which affect the sliding of rubber ring or moving ring (relative dynamic sealing point, common faults). In addition, the medium will also produce a crystal in the rubber ring and the shaft (shaft sleeve), and there will be solid substances at the spring, which will make the sealing cover open. (2) overheating Because of the heat on the sealing surface, the temperature of the rubber ring should be lower than the design specification. The use of fluorine rubber and PTFE temperature is 216 DEG C, the use of NBR temperature is 162 DEG C, although they are able to withstand the high temperature, high heat but because the sealing surface is generated, so the rubber ring is dangerous to sulfide, eventually lose their elasticity and leakage. (cold zone is cold and crisp) The sealing surface will also cause crystallization of the medium due to heat, such as carbon deposition, which causes the sliding parts to be stuck and the sealing surface to be condensed. In addition, some polymers are coking because of overheating, and some fluids lose lubrication and even flame when overheated. Overheating can increase the corrosion rate as well as change the condition of the medium. The deformation of the metal parts, the cracking of the alloy surface and the cracks in some of the coatings, the design of balanced mechanical seals should be adopted to reduce the specific pressure and prevent overheating. (3) over tolerance Tolerance is correct, it is necessary for the installation of mechanical seal, shaft (sleeve) must have the appropriate surface roughness and the correct size, but the manufacturer provides little tolerance data, these data is key to the installer. (relying on experience and common sense) The dimension accuracy and form tolerance of the mechanical seal must comply with the requirements of the drawing, and the over tolerance will lead to premature sealing failure.