Atomic emission spectrum analysis has its unique advantages, especially suitable for pre-furnace analysis, so that it has become an essential analytical means for metal smelting and casting industry, and its characteristics are as follows:

(1) Multi-element simultaneous detection capability. Simultaneous determination of multiple elements in a sample. After each sample is excited, the different elements emit characteristic spectra, so that multiple elements can be determined simultaneously. For complex products, the more analytical elements are required to heal, and the economic benefits are good.

(2) Fast analysis speed. If the photoelectric direct reading spectrometer is used to analyze the sample without chemical treatment, the sample taken in the furnace can be excited on the sample table as long as the surface oxide is polished off, eliminating the trouble of drilling the sample for chemical analysis. For aluminum and copper, zinc and other non-ferrous metal samples, you can use a small lathe to remove the surface oxide can be directly measured. From sample excitation to the computer to report the element analysis content only 20-30 seconds, the speed is very fast, which is conducive to shortening the smelting time and reducing the cost. Especially for those elements that are easy to burn, it is easier to control their final composition.

(3) High accuracy. The analysis accuracy is very high, can effectively control the chemical composition of the product, ensure that it can meet the national standard specifications, and even the alloy composition can be controlled to the lower limit of the specification to save the consumption of intermediate alloys or ferroalloys.

(4) Less sample consumption.

(5) The analytical data can be printed out from the computer or stored on a floppy disk as a permanent record.

In short, from a technical point of view, photoelectric spectral analysis, it can be said that there is no more effective instrument than it can be used for rapid analysis in front of the furnace, with so many characteristics and can replace it. Therefore, the world's smelting, casting and other metal processing enterprises are competing to use this kind of instrument to become a conventional means of analysis, from the guarantee of product quality, from the economic benefits and other aspects, it is a very favorable analysis tool.

     Demagnetization is the loss of magnetic field strength in magnets. Every magnet has a specific temperature, which is called the Curie temperature, at which it loses its magnetism. If magnets cool to room temperature, they may not regain previous super strong magnetic strength.

What causes strong neodymium magnets to demagnetize?

1. Influence of external magnetic field

     External magnetic fields, especially strong magnetic fields, can cause magnets to lose strength. The alignment of the magnetic domains can be disrupted when exposed to the north and south poles of another magnet.

2. Effects of heat exposure

     Heating permanent rare earth neodymium magnets to the Curie temperature causes its magnetic domains to randomize. Even if the magnet cools down, its original magnetic force may be reduced.

3. The role of working temperature

     Magnets' operating temperature is the highest temperature the magnets can withstand without significant loss of magnetic force. Neodymium magnets have a maximum operating temperature above which they may become demagnetized.

How to determine if neodymium magnets have been demagnetized?

     One must observe its magnetism and properties to determine whether strong power neodymium magnets have been demagnetized. Loss of strength or weakening of the magnetic field may be indicative signs. However, to understand the complete guide to demagnetization, one should understand the inherent properties of magnets such as permeability and temperature tolerance. Using tools or exposing a magnet to another magnet (such as an old magnet from the North) can provide further insight into its current state.

How to remagnetize a demagnetized neodymium magnet?

1.Make sure the demagnetized magnets are at room temperature.

2.Use stronger magnets or current to expose the demagnetized magnet to a strong magnetic field.

3.Make sure the magnets are aligned with the magnetization direction.

     PS：Make sure the magnets are only heated to its Curie point. Additionally, instruments are used to measure the strength that the magnet regains after remagnetization.

     Ndfeb magnets can be divided into bonded NdFeb and sintered NdFeb. The difference between the two magnets is mainly in the production process: bonded neodymium magnet is injection molding by adding NdFeb magnetic powder to the adhesive; sintered neodymium magnet is vacuumed and molded by high temperature heating.

     1. Custom sintered neodymium magnet

     In the process of sintering magnet manufacturing, neodymium magnet powder is mixed with appropriate additives and heated by high temperature sintering process. In the sintering process, the neodymium magnet powder particles will be combined to form a stable magnetic structure, thus forming a magnet with strong magnetism. Generally, through sintering, only blank can be produced, and then through mechanical processing (such as wire cutting, slicing, grinding, etc.) to become a magnet of various shapes. Sintered NdFeb is a hard and brittle material that is difficult to process, with large loss during processing. But the advantage is that sintered magnets usually have a high magnetic force and magnetic energy product, and have good temperature stability.

     Sintered Ndfeb is generally divided into axial magnetization and radial magnetization, and the magnetization direction can be customized according to the required work needs, while sintered Ndfeb has poor corrosion resistance and is easy to oxidize, so it is necessary to deposit on its surface, common nickel plating, galvanized, epoxy plating and so on.

     2. Custom bonded neodymium magnet

     The bonded neodymium magnet is used adhesive to bond the neodymium magnet powder with other metal elements, so it is magnetic in all directions and resistant to corrosion. In the manufacturing process, neodymium magnet powder and adhesive are mixed to form a magnet by pressure or injection molding. Because it is molded by injection molding, the density is generally only 80% of the theoretical, and the magnetism is weaker than the sintered neodymium magnet. But the manufacturing method of bonded neodymium magnets allows for more complex shapes and structures, and can be used in combination with other materials.

     The above is the introduction of the difference between the production processing technology of bonded NdFeb and sintered NdFeb. Both types of custom neodynium permanent magnets have their advantages and application scenarios. Sintered magnet is commonly used in applications that require high magnetic force and temperature stability, such as engines, sensors, and nuclear magnetic resonance equipment. Bonded magnet is suitable for applications that require custom shapes and structures, such as magnetic pusher pins, magnetic labels, etc.

     In short, the manufacturing process of sintered magnet and bonding magnet is different, and the choice of the appropriate process depends on the specific application needs.

Inspection of Stainless Steel Reducers
1. Geometry analyses of stainless steel reducers
The distribution trends of wall thickness of big and small concentric reducers are exactly the same. From the large end face to the section close to the small end face, the wall thickness changes from thin thickness to thick one. The inner hole of the small end has been turned after forming, and part of the wall thickness has been removed. However, the wall thickness of end faces of small ends is thinner than that of end faces of large ends, which is exactly the opposite of the eccentric reducer. This is caused by the manufacturing process. When the wall thickness of the axial section changes, there is obvious regularity for changes between the warp threads, but there is also a certain degree of dispersion.

2. Analyses of strength
The distribution trends of surface hardness of the large and small eccentric reducers are roughly the same, but they are not completely the same. The main difference is the hardness of the small end. The hardness of the small end of small eccentric reducers is higher, while the hardness of that of large eccentric reducers is lower. The tensile strength of the sample is 6.1% and 11% higher than the estimated strength value of the empirical formula. The yield strength and tensile strength of the sample 1 were increased by 9.0% and 2.0% respectively before production, and those of the sample 2 were increased by 26.4% and 8.8% compared with before production).

Large-diameter seamless steel pipes can be divided into straight seam arc welded steel pipes and straight seam submerged arc welded steel pipes according to traditional processes. The production process of straight seam welded pipe is simple, low cost, rapid development, and high production efficiency.

First, the steps to explain the large-diameter seamless steel pipe
1. Large-diameter seamless steel pipes are made of a single piece of metal and have no seams on the surface. They are called seamless steel pipes. Seamless steel pipes have hollow sections and are suitable for transporting fluids such as oil, water, and some solid materials.
2. Large-diameter seamless steel pipes are widely used to manufacture structural parts and mechanical parts, such as oil drill pipes, automobile drive shafts, bicycle frames, steel scaffolding, etc. Straight seam steel pipe refers to a steel pipe in which the weld seam is parallel to the longitudinal direction of the steel pipe. When seamless pipes and straight-seam pipes have the same diameter and wall thickness, the pressure and robustness of seamless pipes are much greater than that of straight-seam pipes.
3. Large-diameter seamless steel pipes and welded steel pipes are steel pipes made by crimping steel plates or steel strips.

Second, a complete list of methods for large-diameter seamless steel pipes
1. Seamless steel pipes have much higher corrosion resistance, pressure resistance, and high-temperature resistance than welded steel pipes. When seamless pipes and straight-seam pipes have the same diameter and wall thickness, the pressure and robustness of seamless pipes are much greater than that of straight-seam pipes.
2. Large-diameter seamless steel pipe has a hollow section and is suitable for transporting fluids, such as oil, water, and some solid materials. The production process of straight seam welded pipe is simple, low cost, rapid development, and high production efficiency.
3. Seamless steel pipes have much higher corrosion resistance, pressure resistance, and high-temperature resistance than welded steel pipes. A welded steel pipe is a steel pipe made of steel plates or steel strips pressed together.

Carbon steel flange is a kind of common connecting pipe component, which is widely used in petroleum, chemical, natural gas and other industries. It is usually made of carbon steel, with high strength, corrosion resistance and high temperature characteristics, suitable for a variety of harsh working environment.

There are many types of carbon steel flanges, including blind plate, butt welding, thread, flange, etc. . Each type has a different way of connecting and usage scenarios to meet a variety of different needs. Butt-welding flange is the most common one, it can be fixed to the pipeline through welding to ensure the stability and sealing of the connection. Thread flange is suitable for low pressure environment, through the thread connection to achieve pipe connection. Blind flange used to block the flow of fluid in the pipeline, often used for pipeline closure or repair.

One of the advantages of carbon steel flanges is that the material strength is high, able to withstand high pressure and high temperature working conditions. It can be used in harsh environment for a long time, with a long life. The carbon steel flanges also have good corrosion resistance and are not easy to be corroded and oxidized when in contact with various media, thus ensuring the safety and reliability of pipelines.

Carbon steel flanges are relatively simple to install and maintain and can be quickly removed and replaced. Its structure design is reasonable, has the good sealing, can prevent the leakage and the outside impurity entering. At the same time, carbon steel flanges have lower cost and play an important role in the design and construction of pipeline system.

In a word, as an important part of connecting pipeline, carbon steel flange has the characteristics of high strength, corrosion resistance and high temperature resistance. The utility model has the advantages of reasonable structure design, simple installation, good sealing performance and lower cost, and is widely used in petroleum, chemical industry, natural gas industry and the like. Carbon steel flanges are a reliable and economical choice for both new construction and maintenance projects.

To determine the size of a flange, you will need to measure the diameter of the flange.  Here's how you can do it:

1.  Measure the outside diameter (OD) of the flange: Use a measuring tape or a caliper to measure the distance across the outer edge of the flange.  Make sure to measure from one side to the opposite side, passing through the center.

2.  Determine the flange size: Once you have the measurement of the outside diameter, you can refer to a flange size chart or consult the manufacturer's specifications to determine the corresponding flange size.

It's important to note that flange sizes are typically specified in standard dimensions, such as inches or millimeters.  Additionally, some flanges may have specific designations based on their intended application or industry standards (e.g., ANSI, ASME, DIN, etc.).

If you're unsure or need accurate measurements, it's recommended to consult a professional or refer to industry standards for precise flange sizing.

It mainly uses steel wire brush and other tools to polish the steel surface, which can remove loose or raised oxide skin, rust, welding slag, etc.

Generally, chemical and electrolytic methods are used for pickling treatment. Chemical pickling is only used for pipeline corrosion protection, which can remove oxide skin, rust and old coating. Sometimes it can be used as the reprocessing after sand blasting. Although chemical cleaning can make the surface reach a certain degree of cleanliness and roughness, its anchor pattern is shallow and easy to pollute the environment.

Spray (throwing) rust removal is a high-speed rotation of spray (throwing) blades driven by a high-power motor, so that steel sand, steel shot, wire section, minerals and other abrasives can spray (throwing) on the ASTM A106 A53 Gr. B Carbon Steel Seamless Fluid Pipe surface under the centrifugal force, which can not only completely remove rust, oxides and dirt, but also achieve the required uniform roughness under the action of strong impact and friction of abrasives. After spraying (throwing) and removing rust, not only the physical adsorption on the pipe surface can be expanded, but also the mechanical adhesion between the anticorrosive coating and the pipe surface can be enhanced. Therefore, spraying (throwing) is an ideal way to remove rust. Generally speaking, shot blasting (sand) is mainly used for inner surface treatment of pipes, while shot blasting (sand) is mainly used for outer surface treatment of pipes.

Transformers often require/use iron cores because they operate on magnetic forces, which are difficult to understand when sharing certain characteristics with good old "electricity" (ohms, volts, amperes, etc.). Let's try some simplified ways to get the overall idea.

Start with a screwdriver - just a cylindrical coil. If we let the current flow through, a magnetic field (we call it the H field) is formed. The field depicted with the imagined field line flows up through the center of the coil, then disperses again after leaving the cylinder, then reassesses and re-enters the other end. You've seen the picture in the textbook. The magnetic field is strong and contained inside the cylinder (ID), while the magnetic field strength is weak outside (OD) because it diffuses in space. If the H magnetic field interacts with "anything" around the coil, whether it is vacuum, air or iron, it produces what we call a B magnetic induction field within the "material", the strength of which depends on the strength of the magnetic field. The properties of "matter" are called "permeability". For a given magnetic field strength H, vacuum or air forms a relatively weak induction field B, while iron forms a very strong sensing field (1000 times stronger).

If we make a second coil (solenoid valve) and parallel it to the first coil in the air, a portion of the weak air sensing field B flows through the center of the second coil. If we change the current in the first coil, its B field will change slightly, as will the B field flowing through the second coil (absolutely by a small margin). This is not only because the entire B magnetic field is weak, but also because only a portion of the entire B magnetic field actually passes through the second coil. Recall maxwell's equation, saying that the voltage sensed in the coil depends on the magnitude of the change through its B field. Therefore, in our case, since the B-field change through the second magnetic field is very small, we can expect only one weak voltage to be sensed in the second coil.

To make it better, we can place a piece of iron in the center of the first coil. This will make the B field in the iron stronger than the B field in the air. In addition, we can extend the iron sheet into a ring so that it passes through the second coil. (We've made a transformer core ). Most of the enhanced B magnetic field from the first coil now passes through the iron into the second coil, and the magnetic field change caused by the current change in the first coil is amplified, resulting in a greater inductive voltage in the second coil. Coil.

That's why we use iron core simplification in many, but not all, transformers.

LC blade conventional products for paper manufacturing industry include blade for cutting rest concreted paper pulp, separating blade in pulp period, all kinds of scraper in coating period and circular rewinder cutting blade, slitter blade, crossing-cutting blade in final processing period. Among them, the lcknife circular slitting blade which used in processing paper for daily use is most popular in the market, like cutting blade, punching blade, rolled paper slitting blade and pipe cutting blade.