ERW (Electrical Resistance Welding) pipes are made by cold forming steel coil into a round cylindrical shape. ERW pipe is formed of steel coil, and the weld seam runs parallel to the pipe. Because the breadth of the coil is the same as the circle of the pipe, widths are limited to 24 inches. It is used to transport oil, natural gas, and other vapor-liquid items and may meet a variety of high and low pressure requirements.
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What is Internal Coated Pipe?
Internal pipeline coatings must be constructed to withstand the high impact caused by these fast-moving particulates. Solid particles in oil and gas fluids include sodium chloride, potassium chloride, other salts, carbonates, and sulfates, partially polymerized oils such as waxes and paraffin, as well as silica, dirt, and greases. Some of the particles disintegrate in the fluid, while others remain suspended. These particulates become fiercely corrosive missiles when they travel through pipes at speeds nearing 200 mph.
For steel potable water transmission coated pipe, there are five common types of interior coating or lining material. Coal tar enamel, cement mortar, liquid-applied epoxy, fusion-bonded epoxy (FBE), and polyurethane are among the materials on the list (PU). Each of these lining technologies has advantages and disadvantages. Furthermore, each interior coating type has surface preparation and application requirements.
What is External Coated Pipe?
Coated pipelines for the oil and gas industry can be located all over the world. Pipelines can be installed above ground, underground, or immersed in fresh or saltwater. External pipeline coatings must be built to resist such a wide range of climatic conditions. Soil stress, soil-borne pollutants, and saltwater all pose significant difficulties to the performance of external pipeline coatings. External coatings must also be resistant to indigenous bacteria, other flora, wastewater, and the chemicals and solvents used in hydrocarbon processing. Pipelines can be found in the hot desert, where temperatures frequently surpass 100°F, and in Alaska, where temperatures can drop below -76°F. Subsurface conditions in permafrost zones, where ground temperatures rarely surpass 32°F, make subterranean pipe construction challenging and virtually always necessitate above-ground pipeline installations.
Why pipe coating is important?
Pipeline coating is critical to the design and durability of any pipeline. The coating protects the pipe from extremes in temperature, chemicals, pressure, abrasion and other harsh conditions. Pipeline coating can be done on both internal and external surfaces of the pipe using a variety of materials that range from soft metallic compounds to rigid thermoplastics. It also can serve as an outer layer for externally laid pipelines on land or in water.
Types of Coated Pipes
FBE Coated Pipe
The Fusion Bonded Epoxy (FBE) coating prevents corrosion on pipe surfaces. Double or triple layers of FBE may even improve friction and abrasion resistance. In 3-layer PE/PP coating systems, FBE coating is also employed as the priming layer.
At temperatures ranging from 220 to 235°C, the electrostatic epoxy powder is sprayed onto a pipe. When the epoxy powder reaches the hot pipe surface, it melts and forms a uniform layer of epoxy coating on the pipe.
Dual Layer FBE Coated Pipe
Dual-layer FBE is used for a variety of service applications, including directional drilling, anti-abrasion for road and river crossings, and oil, gas, and waterworks pipes. This coating, like single layer FBE (above), can be applied on a wide range of outer diameter (OD) sizes, from 3.5″ to 48″. In most situations, the top layer of abrasion resistance protects against erosion.
2LPE Coated Pipe
Two-layer extruded polyethylene coating (2LPE) refers to two layers of pipeline protection. Mastic-based adhesives and polyethylene copolymers are used in the two-layer construction. This provides excellent corrosion prevention, especially at high temperatures.
2LPP Coated Pipe
The 2LPP System is a multi-layer powder coating system made up of two functional components. This anti-corrosion system is made up of a layer of polypropylene followed by a coating of high-performance fusion-bonded epoxy (FBE).
3PE Coated Pipe
To solve the disadvantages of each anti-corrosive procedure, the three-layer polyethylene (3PE) anti-corrosive coating combines the properties of epoxy powder FBE and two-layer PE coating. The principal anti-corrosive agent is FBE. PE primarily protects FBE (mechanical damage resistance) and has excellent water penetration resistance. The three-layer polyethylene coating method provides outstanding mechanical qualities to satisfy the coating material’s properties, and the coating can operate at temperatures as high as 50°C (low density and medium density POLYETHYLENE) or 70°C (high-density POLYETHYLENE) (high-density polyethylene).
3PP Coated Pipe
A bottom layer of epoxy powder, an intermediate layer of binder, and an outside LAYER of PP (polypropylene) jacket comprise the three-layer polypropylene (3PP) anti-corrosive coating. The 3PP incorporates all of the benefits of the 3PE while significantly improving its temperature performance in service. 3PP coating is mostly utilized as an anti-corrosion pipeline for transporting high-temperature media and as a pipeline anti-corrosion layer in desert locations with high surface temperatures and lengthy sunshine duration. As a result, subterranean water, gas, and oil pipelines have become increasingly popular in places with high surface temperatures and long daylight duration.