Alloy Steel Pipes

Materials of alloy steel pipes 
Alloy steel pipes have good hardness, which are widely used for pipelines for transporting oil, natural gas, gas, water and certain solid materials. The common alloys are ferroalloys, ferro-chromium alloys, iron-nickel alloys, aluminum alloys(light weights) and copper alloys(good thermal conductivity). The main materials include 16-50Mn, 27SiMn, 20-40Cr, 12-42CrMo, 16Mn, 12Cr1MoV, T91, 27SiMn, 30CrMo, 15CrMo, 20G, Cr9Mo, 10CrMo910, etc. Alloy steel pipes made from 16Mn belong to low alloy steel pipes.
 
Applications of alloy steel pipes
Alloy steel pipes are mainly used for high-pressure and high temperature pipelines and equipment such as power plants, nuclear power, high-pressure boilers, high temperature superheaters and reheaters.
 
Three expressions of alloy steel pipe specifications
1. The first one is the outer diameter plus wall thickness. For example, an alloy steel pipe with an outer diameter of 57mm can be indicated by 57x3.
2. The second one is using the inner diameter, that is, the nominal inner diameter. For example, an alloy steel pipe with an outer diameter of 57mm is indicated by DN50.
3. The third one is the inch. For example, an alloy steel pipe with an outer diameter of 57mm can be indicated by 2 inches (1 inch equals to 25.4mm.)
 
Specific welding steps of alloy steel pipes
Welding processes of alloy steel pipes are heating before welding, quenching and tempering after welding.
 
Heating
Before welding the alloy steel pipe, it should be heated, and weld it after the temperature is controlled for 30 minutes. The heating and virtual beam temperature tempering of welding are actively operated by the temperature control cabinet for temperature adjustment. Adopt far infrared tracking heat treatment furnace plates. Intelligently and actively set the graph and record the graph, and use the thermal resistance to accurately measure the temperature. The thermal resistance measuring point is from 15mm to 20mm away from the edge of the weld during heating.
 
Welding methods
1. In order to prevent welding deformation of the alloy steel pipe, each column joint is welded symmetrically by two people, and the welding direction is from the middle to the two sides. After welding one to three layers, reverse planing should be carried out. After the carbon arc gouging is used, the welding equipment needs to be polished. The welding surface should be nitridation treated to show the metal texture and prevent the surface carbonization from causing cracks. The outer hole is welded once, and the remaining inner holes are welded once.
2. When welding alloy steel pipes with two layers, the welding direction should be opposite to that of the layer of alloy steel pipes. The butt welds of each layer are separated by 15 to 20mm.
3. The welding current, welding speed and number of overlapping layers of multiple welding machines should be maintained.
4. In welding, you must start welding from the pilot arc board and finish welding on the pilot arc board. Cut, polish and clean after welding.
 
Quenching and tempering after welding
After the seam are welded, it should be tempered within 12 hours. If the alloy steel pipe cannot be quenched and tempered immediately, heat preservation and slow cooling should be adopted. When the alloy steel pipe is tempered, temperatures of the two thermal resistances should be measured and the thermal resistance should be welded on both sides of the seam.

Technical requirements for steel pipes

This technical specification is suitable for the bidding for the procurement of steel pipe projects.

Executive standards

The steel pipe shall meet the following standards:

Quality standard like Spiral Welded Submerged Arc Welded Steel Pipes for Urban Heating CJ/T3022-1993 or Technical Delivery Conditions of Oil and Gas Industry Transportation Steel Pipes GB/T9711.1-2017 should be implemented for spiral welded pipes.

Seamless Steel Pipe for Fluid Transportation GB/T8163-2008 should be carried out as quality standards for seamless steel pipes.

Technical requirements for steel pipes

Materials

The steel pipe should be made of spiral seam welded steel pipes with Q235B.  The seamless steel pipe should adopt 20# steel.

Technical specifications

The quality and size of spiral seam welded steel pipes should conform to IS09330-1 or GB9711.1~2017 standards.

Spiral seam welded steel pipes should ensure that the minimum yield strength is greater than 235N/mm2.

Weld joints of steel pipes must meet the technical requirements of DIN1626 or GB3323-87.

Specifications, weights and errors of steel pipes

The supply of steel pipes shall comply with the relevant regulations in the latest GB9711.1-2017 or GB8163-2008.

The normal supply length of the steel pipe should be 12m with a length deviation of 0/+25mm.  When the length of the steel pipe is less than 12m due to the valve, compensator or pipeline turning, it should be supplied according to the actual length on site.

The thickness deviation requirements of the raw material steel plate of the steel pipe: when DN is 800mm, the negative thickness deviation should be smaller than or equal to 0mm.  When DN is greater than 800 and smaller than or equal to 1100mm, the thickness negative deviation should be less than or equal to 0mm.  When DN is greater than 1100 and smaller than or equal to 1200mm, the thickness negative deviation should be less than or equal to 3%.

The end of the steel pipe should be grooved.  The groove angle should be 30° and the deviation 0°/5°.  The size of the blunt edge should be 1.6±0.8mm.

The end surface of the steel pipe shall be perpendicular to the axis of the steel pipe.  When the nominal outer diameter is less than 508mm, the limit deviation shall not be greater than 1.5mm.  When the nominal outer diameter is greater than or equal to 508, the limit deviation shall not be greater than 2.0mm.

The ovality of the steel pipe end within 100mm shall not exceed ±1%D.

Requirements for manufacturers

In order to ensure the quality of the project, the following requirements are put forward for the materials and manufacturers of steel pipes and fittings:

The steel quality standards of steel pipes are equal to or higher than those of famous steel pipe manufacturers in China.

The quality standard of the steel pipe is equal to or higher than the product standard produced by the bidder, and the selected manufacturer must be approved by the tenderer and indicate in the bidding document.

At the same time, photocopies of the delivery quality certificate of the steel pipe raw materials, the quality certificate of the steel pipe, the special equipment manufacturing license (pressure pipe) that the manufacturer should have, and the inspection report issued by the local quality inspection department must be attached to the bidding documents.

Large-Diameter Seamless Steel Pipe Related Details

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.

Introduction of carbon steel flanges

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.

Manufacturing method of seamless steel pipe

Seamless steel pipe is a kind of long steel with hollow section and no joint around.  The seamless steel pipe has hollow section and can be used as the pipeline for conveying fluid, such as oil, natural gas, gas, water and some solid materials.  Compared with solid steel such as round steel, seamless steel pipe is lighter in weight when its bending and torsion strength is the same.  It is a kind of economic section steel, which is widely used in the manufacture of structural parts and mechanical parts, such as oil drill pipe, automobile transmission shaft, bicycle frame and steel scaffold used in construction.  Using seamless steel pipe to make annular parts can improve the material utilization rate, simplify the manufacturing process, save materials and working hours, such as rolling bearing rings, Jack sleeves and so on.  Steel pipe is also an indispensable material for all kinds of conventional weapons.  Gun barrel and barrel should be made of steel pipe.

 

According to different production methods, it can be divided into hot-rolled pipe, cold-rolled pipe, cold drawn pipe, extruded pipe, etc.

1.Hot rolled seamless steel pipe is usually produced on the automatic pipe mill.  After checking and removing the surface defects of the solid tube blank, it is cut into the required length, centring on the end face of the piercing end of the tube blank, and then sent to the heating furnace for heating and piercing on the piercing machine.  In the process of piercing, a cavity is gradually formed inside the tube blank under the action of the roller and the plug, which is called the blank tube.  Then it is sent to the automatic pipe rolling mill to continue rolling.  Finally, the wall thickness is adjusted by the whole machine, and the diameter is calibrated by the sizing machine to meet the specification requirements.  It is an advanced method to produce hot rolled seamless steel tube by continuous pipe mill.

2.  In order to obtain smaller size and better quality seamless tubes, cold rolling, cold drawing or a combination of both must be used.  Cold rolling is usually carried out on a two high mill.  The steel tube is rolled in an annular pass composed of a variable cross-section circular groove and a stationary conical plug.  Cold drawing is usually carried out on 0.5-100t single chain or double chain cold drawing machines.

 

3.  In extrusion process, the heated tube blank is placed in a closed extrusion cylinder, and the piercing rod and the extrusion rod move together to extrude the extruded part from the smaller die hole.  This method can produce small diameter steel pipe.

Rust removal method of steel pipe

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.

Why use cores in transformers?

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.

Knives for paper industry

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.

Step-by-Step Guide for Using a Synchronized Frameless Sliding Door Roller Kit

Introduction:

Synchronized frameless sliding door roller kits have revolutionized the way we design and use doors. With their sleek and modern appearance, these kits are becoming increasingly popular in homes and offices alike. If you’re a beginner looking to install and use a synchronized frameless sliding door roller kit, this step-by-step guide is here to help you navigate the process with ease. So let’s get started!

Step 1: Gather the Necessary Tools and Materials

Before you begin the installation process, ensure that you have all the required tools and materials. These typically include the roller kit, a measuring tape, a screwdriver, a level, drill bits, screws, and a pencil. It’s important to have everything ready before you start to avoid interruptions during the installation.

Step 2: Measure and Mark the Installation Area

Using a measuring tape, carefully determine the height and width of the door frame. Mark the spots where the roller track and guides will be installed, ensuring they are level and centered. Additionally, mark the desired height for the door handle if applicable.

Step 3: Install the Roller Track and Guides

Using the screwdriver and screws provided, attach the roller track to the top of the door frame. Align the track with the marks made in step 2. Next, install the roller guides on both sides of the door frame, ensuring they are vertically aligned and level with the track. Use a level to guarantee accuracy.

Step 4: Attach the Rollers to the Door

Most roller kits come with detailed instructions on how to attach the rollers to the bottom of the door. Follow these instructions carefully, making sure the rollers are securely fastened and able to move smoothly along the track.

Step 5: Hang the Door on the Roller Track

Lift the door and carefully hang it on the roller track. Ensure that the rollers fit securely into the track and can move freely back and forth.

Step 6: Fine-tune and Test

Check if the sliding door is aligned with the frame and adjust if necessary. Test the door’s movement by sliding it open and closed, ensuring it glides smoothly along the track.

Step 7: Install Handles and Accessories (if applicable)

If your sliding door requires handles or additional accessories, follow the manufacturer’s instructions to install them securely. Pay attention to the placement and alignment of the handles for a polished and functional finished look.

Conclusion:

By following this step-by-step guide, even beginners can successfully install and use a synchronized frameless sliding door roller kit. Remember to take your time and double-check measurements and alignments throughout the process. With patience and attention to detail, you’ll have a stylish and functional sliding door that will enhance any space. Enjoy your newly installed synchronized frameless sliding door and embrace the modern aesthetic it brings!

The Evolution of Sliding Door Systems A Game-Changer in the World of Interior Design

Sliding doors have long been a popular choice when it comes to creating functional and visually appealing spaces. With the introduction of sliding door wheels and hardware for framed doors, a new level of convenience and elegance has been brought to sliding door systems. In this article, we will explore the various components of sliding door systems, with a particular focus on sliding door wheels and rollers.

Sliding Door Wheels: The Backbone of Smooth Functionality

When it comes to sliding door systems, the wheels play a crucial role in ensuring smooth and effortless movement. Traditionally, sliding doors were supported by simple tracks and guides, often resulting in frustrating and noisy operation. However, with the advancement in technology, sliding door wheels have revolutionized the way these systems function.

The sliding door wheels are designed with precision bearings, allowing them to glide effortlessly along the tracks. This not only ensures a quiet and seamless operation but also reduces the wear and tear on the tracks, leading to longer-lasting performance. The introduction of high-quality materials, such as stainless steel or nylon, ensures durability and smoothness, even with heavy doors.

Sliding Door Hardware for Framed Doors: Enhancing Aesthetics and Durability

Framed sliding doors are a popular choice for both residential and commercial spaces. These doors offer a sleek and modern look while providing structural stability. To further enhance the functionality and aesthetics of framed sliding doors, sliding door hardware is an essential component.

Sliding door hardware for framed doors includes handles, locks, guides, and hinges. These hardware pieces not only offer convenience and ease of use but also add an element of style to the doors. With various finishes and designs available, including brushed nickel, matte black, and antique brass, you can customize your sliding doors to perfectly complement your interior décor.

The Complete Sliding Door System Set: A One-Stop Solution

For those looking for a comprehensive solution, a sliding door system set is the perfect choice. These sets typically include all the necessary components for a sliding door system, including tracks, wheels, guides, handles, and more. Investing in a complete set ensures compatibility between all the components and simplifies the installation process.

Whether you are a homeowner, an interior designer, or a contractor, opting for a sliding door system set offers convenience and peace of mind. The ability to choose from various configurations, sizes, and finishes allows you to create a customized sliding door system that meets your specific needs and design preferences.

The Versatility of Sliding Door Systems

Sliding door systems offer a myriad of benefits beyond their functional and aesthetic appeal. They are an excellent space-saving solution, as they do not require additional space for door swing. This makes them ideal for smaller rooms or areas where space optimization is crucial.

Furthermore, sliding doors can seamlessly transition between indoor and outdoor spaces, creating a harmonious connection between the two. By incorporating sliding doors into your design, you can effortlessly merge your living spaces with patios, gardens, or balconies, providing a sense of openness and expanding your available space.

In conclusion, the introduction of sliding door wheels, sliding door hardware for framed doors, and sliding door system sets has transformed the way we approach interior design. These advancements in technology and design have made sliding door systems more versatile, functional, and visually pleasing than ever before. Whether you’re looking to optimize space, enhance aesthetics, or improve functionality, sliding door systems have become an indispensable element in modern architecture and design.