Single-layer pipe
Single-layer anti-corrosion epoxy powder pipe
3PP anticorrosive steel pipe is a steel pipe polypropylene anticorrosive coating, which is characterized by good heat resistance.
3PP Pipes (Three-layer Polypropylene pipes) are known for their enhanced resistance to mechanical damage and corrosion, making them a preferred choice for pipeline infrastructure in various industries.
A 3PP pipe consists of a steel pipe coated with three layers of polypropylene for maximum protection. The three - layer system comprises:
It is widely used in coating for all kinds of major pipeline engineering.
Most of the large pipeline anti - corrosion in China is 3PE coating, and 3PP and 3PE coating belong to the multi - layer coating system, which consists of the bottom epoxy powder, the intermediate layer binder and the outer PP jacket. The performance of PP is similar to that of PE, and 3PP coating is fully capable of being produced with a 3PE production line, and no special 3PP coating operation line is required. However, due to the difference in performance of PP and PE materials, the performance of 3PP and 3PE coatings can be applied to different environments. The advantages of 3PP coating in certain properties make it possible to play a role in areas where 3PE coatings are not applicable. So, there are many pipeline projects abroad that use 3PP anti - corrosion coatings. At present, it is mainly foreign products that are related to the environment. For some countries with high environmental temperatures, and since PP is harder than PE, it can avoid scratch coating.
PP three - tier structure of anti - corrosion pipeline: the first layer of epoxy powder (FBE50 - 100um), the second adhesive (AD) 250 - 400um, the third layer of polypropylene (PP) 1.4 - 4.0mm. The three layers integrate well with the steel pipe, forming a solid coating. The coating temperature can reach up to 110 degrees.
Diameter of Φ159 - Φ1220
Some anti-corrosion methods include painting, covering, and electroplating.
Anti-corrosion coatings act as a barrier layer that prohibits or slows down the formation of corrosion on the underlying metal surface of the carbon steel pipe. By preventing external corrosion with the use of either single or multi-layer anti-corrosion coatings, it ensures precious natural resources and other products reach their destination safely and efficiently.
Anti-corrosion steel pipe is processed through the preservation process, which can effectively prevent or slow down the process in the transport and use of chemical or electrochemical corrosion reaction of steel pipe.
Steel surface treatment is mainly for anti - rust, and the following is the anti - rust process:
First step: Clean the steel surface using a cleaning solvent emulsion. This is to remove oil, grease, dust, lubricants, and similar organic matter. However, it cannot remove rust, oxides, or soldering agents on the steel surface.
Second step: Use rust - removing tools. You need to use a wire brush to remove loose or flaking oxides, rust, and slag. To achieve the desired rust - removing effect, the type of abrasive should be selected based on the original corrosion degree of the steel surface, the required surface roughness, and the coating. For an epoxy layer or two - or three - layer polyethylene coating, using a mixed abrasive of grit and steel shot for blasting is more likely to achieve the desired effect.
Third step: Perform pickling. Generally, chemical and electrolytic pickling are two methods. Using only chemical pickling can cause pipeline corrosion. Although chemical cleaning can achieve a certain level of surface cleanliness and roughness, it causes some environmental pollution.
The three-layer PE (Polyethylene) and PP (Polypropylene) coating process is designed to enhance the corrosion resistance, durability, and mechanical strength of steel pipes.
Finally, emphasize the importance of surface treatment in production and strictly control the process parameters during anti - rust treatment.
When it comes to transporting precious natural resources or other essential products, the integrity of the pipes used plays a pivotal role. Carbon steel pipes, widely utilized in various industries, are susceptible to corrosion over time. This is where anti-corrosion coatings step in as the frontline defense, ensuring the longevity and reliability of the pipes.
Anti-corrosion steel pipe is processed through the preservation process, which can effectively prevent or slow down the process in the transport and use of chemical or electrochemical corrosion reaction of steel pipe.
Anti - corrosion coatings serve as a protective shield against the relentless forces of corrosion that can compromise the structural integrity of carbon steel pipes. These coatings act as a robust barrier layer, strategically designed to inhibit or significantly slow down the formation of corrosion on the metal surface.
In the realm of carbon steel pipes, the battle against corrosion is ongoing. Anti - corrosion coatings emerge as the frontline warriors, safeguarding the structural integrity of pipes and ensuring that resources and products reach their destinations without compromise.
To improve anticorrosion performance and adhesion, an additional layer of epoxy primer is sprayed onto pipe surfaces prior to the adhesive layer and Polyethylene top - layer application. Three Layer Polyethylene is suitable for service temperatures from 60°C to 80°C (85°C peaks). Typical coating thickness is from 1 - 2 mm to 3 - 5 mm.
If a wider service temperature range and high stiffness is required, adhesive and top layers, applied over the primer layer, are based on polypropylene instead of polyethylene. Three Layer Polypropylene is suitable for service temperatures up to 135 °C (140°C peaks). Typical coating thickness is from 1 - 2 mm to 3 - 5 mm.
Three - Layer applications involve a thermoplastic coating applied to steel pipelines as a form of anticorrosion protection. This mechanical resistance is appropriate when the risk of particularly severe coating damages exists. The Three - Layer process involves several steps. First, the pipe surface is blast - cleaned to remove any external residue from the mill or storage. It is then heated and sprayed with a Fusion Bond Epoxy (FBE) primer followed by the application of an adhesive copolymer and polyolefin polymers that are wrap - extruded, one over the other.
Pipeline coating is the most consistent and successful solution for protecting ERW pipes from corrosion, from moisture, other harmful chemicals.
Therefore pipe anti-corrosion layer is an important barrier to prevent soil erosion. A well-known foreign scholar put forward" 3PE france protective layer", so far, anti-corrosion methods is widely used.
1. Increased Flow Capacity – A coating on pipes helps provide a smoother surface thus improving gas and liquid flow within pipes.
2. Reduced Cost – The pipeline coating increases the pipes durability so they can be deployed with minimum maintenance cost even in the harshest environments.
3. Lower energy usage – Various studies have shown that pipelines that are internally coated use less energy for pumping and compression of products through pipes. This helps in increased saving over time.
4. Clean delivery of products – The inhibitors used for the protection products can also be minimized by the use of coated pipes for delivery of products.
Thus, coating of pipelines can help you in reducing your maintenance cost and at the same time providing a corrosion free reliable protection.
The basic principles of urban gas pipeline coating selection:
Product Name | Executive Standard | Dimension (mm) | Steel Code / Steel Grade |
---|---|---|---|
Casting | API 5CT | Ø48.3~273 x WT2.77~11.43 | J55, K55, N80, L80 |
Tubing | API 5CT | Ø48.3~273 x WT2.77~11.43 | J55, K55, N80, L80, H40 |
Product Name | Executive Standard | Dimension (mm) | Steel Code / Steel Grade |
---|---|---|---|
Line Pipes | API 5L | Ø60.3~273.1 x WT2.77~12.7 | A25, A, B, X42, X46, X52, X56, X60, X65, X70, X80 |
Product Name | Executive Standard | Dimension (mm) | Steel Code / Steel Grade |
---|---|---|---|
Electric-Resistance-Welded Steel Pipes | ASTM A135 | Ø42.2~114.3 x WT2.11~2.63 | A |
Electric-Resistance-Welded Carbon Steel and Carbon-Manganese Steel Boiler and Superheater Tubes | ASTM A178 | 42.2-114.3 x 2.11-2.63 | A, C, D |
ERW and Hot-dip Galvanized Steel Pipes | ASTM A53 | Ø21.3~273 x WT2.11~12.7 | A, B |
Pipes for Piling Usage | ASTM A252 | Ø219.1~508 x WT3.6~12.7 | Gr.2, Gr.3 |
Tubes for General Structural Purpose | ASTM A500 | Ø21.3~273 x WT2.11~12.7 | Gr.2, Gr.3 |
Square Pipes for General Structural Purpose | ASTM A500 | 25 x 25~160 x 160 x WT1.2~8.0 | Carbon Steel |
Product Name | Executive Standard | Dimension (mm) | Steel Code / Steel Grade |
---|---|---|---|
Threaded Steel Pipes | DIN 2440 | Ø21~164 x WT2.65~4.85 | Carbon Steel |
Product Name | Executive Standard | Dimension (mm) | Steel Code / Steel Grade |
---|---|---|---|
Screwed and Socketed Steel Tubes | BS 1387 | Ø21.4~113.9 x WT2~3.6 | Carbon Steel |
Scaffolding Pipes | EN 39 | Ø48.3 x WT3.2~4 | Carbon Steel |
Product Name | Executive Standard | Dimension (mm) | Steel Code / Steel Grade |
---|---|---|---|
Carbon Steel Tubes for General Structure Purpose | JIS G3444 | Ø21.7~216.3 x WT2.0~6.0 | Carbon Steel |
Carbon Steel Tubes for Machine Structure Purpose | JIS G3445 | Ø15~76 x WT0.7~3.0 | STKM11A, STKM13A |
Carbon Steel Pipes for Ordinary Piping | JIS G3452 | Ø21.9~216.3 x WT2.8~5.8 | Carbon Steel |
Carbon Steel Pipes for Pressure Service | JIS G3454 | Ø21.7~216.3 x WT2.8~7.1 | Carbon Steel |
Carbon Steel Rigid Steel Conduits | JIS G8305 | Ø21~113.4 x WT1.2~3.5 | G16~G104, C19~C75, E19~E75 |
Carbon Steel Rectangular Pipes for General Structure | JIS G3466 | 16 x 16~150 x 150 x WT0.7~6 | Carbon Steel |
The alloy content of the coil is often lower than similar grades of steel plate, improving the weldability of the spiral welded pipe. Due to the rolling direction of spiral welded pipe coil is not perpendicular to the pipe axis direction, the crack resistance of the spiral welded pipe materials.
Welded steel pipe refers to a steel pipe with seams on the surface that is welded by bending and deforming a steel strip or steel plate into a circular, square or other shape. The blanks used for welded steel pipes are steel sheets or strips.
Since the 1930s, with the rapid development of continuous rolling production of high-quality strip steel and the advancement of welding and inspection technology, the quality of welds has been continuously improved, and the varieties and specifications of welded steel pipes have been increasing.
When the T-shaped welded steel pipe contains Ni, it has strong corrosion resistance in an acidic environment. In an environment containing sulfuric acid or hydrochloric acid, the higher the Ni content in the T-shaped welded steel pipe, the stronger the corrosion resistance. Under normal circumstances, only adding Cr to the T-shaped welded steel pipe can prevent the phenomenon of corrosion. The poor edge condition of the strip is another important cause of misalignment. The effects of changes in mass flow, heat flow density and structural parameters (ratio of helical curvature diameter to T-shaped welded steel pipe diameter Dc/D) on the heat transfer coefficient of saturated bubble boiling in vertical spiral pipes.
During the production of T-shaped welded steel pipes, misalignment occurs from time to time, and there are many influencing factors. In production practice, the steel pipe is often degraded by the wrong side and out of tolerance. Therefore, it is necessary to analyze the reasons for the misalignment of the spiral steel pipe and its preventive measures.
Due to the poor shape and dimensional accuracy of the head and tail of the uncut steel strip, it is easy to cause the steel strip to bend hard and cause misalignment during butt joint. Simulation parameter range: vertical pipe: pipe diameter D=10mm, pipe length L=660mm; three types of vertical T-shaped welded steel pipe: pipe diameter D=10mm, the change of the ratio of the curvature diameter of the T-shaped welded steel pipe to the spiral pipe diameter is Dc /D=15, 20, 25, helical pitch Pt=20mm, tube lengths are L=503mm, L=660mm, L=817mm respectively. Mass flow G=200~400Kg/(m'2 s), heat flux density q=5~15KW/m'2, saturation pressure p, saturation=0.414880MPa, saturation temperature T, saturation=283.15K.
The technical requirements and inspection of welded pipes are based on the provisions of the GB3092 "Welded Steel Pipes for Low-Pressure Fluid Transmission". It can be delivered according to fixed length or double length. The surface of the steel pipe should be smooth, and defects such as folds, cracks, delamination, and lap welding are not allowed. The surface of the steel pipe is allowed to have minor defects such as scratches, scratches, weld misalignment, burns and scars that do not exceed the negative deviation of the wall thickness. The thickening of the wall thickness and the presence of inner seam weld bars are allowed at the weld.
Welded steel pipes should be subjected to mechanical performance test, flattening test and flaring test, and must meet the requirements of the standard. When the steel pipe should be able to withstand the internal pressure, carry out a pressure test of 2.5Mpa, and keep it for one minute without leakage. The method of eddy current flaw detection is allowed to replace the hydrostatic test. The eddy current flaw detection is carried out according to the standard of GB7735 "Steel tube eddy current flaw detection inspection method". The eddy current flaw detection method is to fix the probe on the frame, keep a distance of 3~5mm between the flaw detection and the weld seam, and conduct a comprehensive scan of the weld seam by the rapid movement of the steel pipe. The flaw detection signal is automatically processed and sorted by the eddy current flaw detector. To achieve the purpose of flaw detection. The welded pipe after the flaw detection is cut off according to the specified length with a flying saw, and it is rolled off the assembly line through the turning frame. Both ends of the steel pipe should be chamfered with flat ends, printed with marks, and the finished pipes are packed in hexagonal bundles before leaving the factory.
Straight seam steel pipe is a steel pipe whose weld seam is parallel to the longitudinal direction of the steel pipe. Generally, its strength is higher than that of straight seam welded pipe. Narrower billets can be used to produce welded pipes with larger diameters, and the same width of billets can be used to produce welded pipes with different pipe diameters. But compared with the straight seam pipe of the same length, the weld length is increased by 30~100%, and the production speed is lower. So what are its processing methods?
The surface quenching and tempering heat treatment of straight seam welded pipe is usually carried out by induction heating or flame heating. The main technical parameters are surface hardness, local hardness and effective hardened layer depth. Vickers hardness tester can be used for hardness testing, and Rockwell or superficial Rockwell hardness tester can also be used. When the surface heat treatment hardened layer is thick, the Rockwell hardness tester can also be used. When the thickness of the heat-treated hardened layer is 0.4-0.8mm, the HRA scale can be used, and when the thickness of the hardened layer exceeds 0.8mm, the HRC scale can be used.
If the parts require high local hardness, local quenching heat treatment can be carried out by means of induction heating. Such longitudinal welded pipes usually need to mark the location of local quenching heat treatment and local hardness value on the drawing. Hardness testing of longitudinally welded pipes shall be carried out in the area. The hardness testing instrument can use a Rockwell hardness tester to test the HRC hardness value. If the heat-treated hardened layer is shallow, a surface Rockwell hardness tester can be used to test the HRN hardness value.
The three hardness values of Vickers, Rockwell and Superficial Rockwell can be easily converted to each other and converted into hardness values required by standards, drawings or users. The corresponding conversion tables are given in the international standard ISO, the American standard ASTM and the Chinese standard GB/T.
When you partner with Sunny Steel, you can stop worrying about meeting deadlines thanks to our responsive and timely service. You'll also say goodbye to unnecessary shopping around. Instead, you'll get white glove service from an expert who understands your needs and can get you the materials you need quickly.