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The roughness of carbon steel pipe (cs pipe) refers to an index of surface quality, which is usually used to describe the smoothness of the surface of carbon steel pipe after processing. It is usually expressed in Ra value (average roughness) or Rz value (maximum peak height). The measurement of the roughness of carbon steel pipes can be carried out by optical methods, mechanical methods and electrical methods.
The greater the surface roughness of the substrate, the greater the corrosion rate, and the more serious the corresponding "over-pickling" phenomenon. Only by effectively controlling the "over-pickling" phenomenon can the clean production level of the pickling process be effectively improved. If there is galvanized Or surface treatment such as pickling, can be considered according to Ra12.5.
The impact of carbon steel pipe surface roughness on its use:
The surface roughness of carbon steel pipe has a great impact on the use of steel pipe. First, excessive surface roughness of steel pipe will affect the resistance, vortex, and friction of the fluid, reduce the pipeline transportation efficiency and the stability of fluid flow. Secondly, in some special industries, such as pharmaceuticals and food industries, excessive surface roughness of steel pipes will affect the safety of their use and even cause product quality problems. Therefore, for these industries, the requirements for the surface roughness of steel pipes are higher. In addition, excessive smoothness of the pipeline surface is also prone to insufficient fluid shear force, affecting the state and flow performance of the fluid pipeline.
How much should the surface roughness of steel pipes reach?
For different industries, the requirements for the surface roughness of steel pipes are different. Generally speaking, the surface roughness of steel pipes should be controlled between Ra 1.6-6.3μm and Rz 10-50μm. However, in special industries, such as pharmaceuticals and food industries, the requirements for the surface roughness of steel pipes are higher, reaching between Ra 0.4-1.6μm and Rz 3.2-10μm.
What are the methods for measuring the surface roughness of carbon steel pipes?
Common measurement methods include surface roughness meters, measuring the contour length of the media on a computer wave graph, etc. At present, the surface roughness meter is one of the most commonly used methods for measuring the surface roughness of pipelines. The microscopic unevenness of the pipeline surface is output as a digital signal through an electronic detector and a scanner, and then the surface roughness value is obtained through computer processing.
What is the relationship between pipeline surface roughness and pipeline fluid operation?
The surface roughness of the pipeline is closely related to the friction resistance and damping coefficient of the pipeline fluid. At low Reynolds numbers (Re<2300), the friction resistance and damping coefficient increase with the increase of pipeline surface roughness; at high Reynolds numbers (Re>4000), the friction resistance and damping coefficient decrease with the increase of pipeline surface roughness. Therefore, in order to ensure the fluidity and accurate calculation of the flow rate of pipeline fluids, it is necessary to reasonably control and optimize the pipeline surface roughness.
How to control the surface roughness of steel pipes?
To control the surface roughness of steel pipes, it is necessary to start from multiple aspects such as raw materials, production processes, lubrication, and maintenance. First of all, it is very important to choose the right raw materials to control the surface roughness of the steel pipe. Secondly, during the production process, technical control should be strengthened, the production process should be strictly implemented, and the operation of each link should be standardized and normalized. In addition, during use, lubrication and maintenance should be done well, and steel pipes with unqualified surface roughness should be discovered and handled in time.
How to optimize the surface roughness of carbon steel pipes?
To optimize the surface roughness of pipelines, effective measures need to be taken to treat and improve the surface of pipelines, including galvanizing, polishing, internal coating and lining. It can not only improve the compressive strength and corrosion resistance of the pipeline, but also reduce the roughness of the pipeline surface, reduce the retention of scale, sediment and bacteria, and ensure the stability and safety of pipeline operation.
What is the surface roughness of copper pipes?
The surface roughness of copper pipes refers to the microscopic geometric shape characteristics of tiny peaks and valleys on the processed surface, which is usually expressed by the following parameters:
Ra (arithmetic mean deviation): the most commonly used indicator, indicating the arithmetic mean of the absolute value of the profile deviation
Rz (maximum height roughness): evaluates the peak-to-valley range of the surface
Rmax (maximum height at a single point): the maximum drop within a single measurement section
Standard range of copper tube surface roughness:
As a common metal material, copper tubes are widely used in refrigeration, heating, water supply and drainage, etc. Its surface roughness is one of the important indicators for measuring the quality of copper tubes, which directly affects the performance and appearance of copper tubes. According to industry standards, the surface roughness of copper tubes is usually between Ra 0.4 and 0.8 microns. This range can not only ensure the smoothness of the inner wall of the copper tube, reduce fluid resistance, but also ensure the beauty of the outer surface of the copper tube.
Factors affecting the surface roughness of copper tubes:
1. Grain size: The surface roughness of copper tubes is closely related to grain size. Experiments show that within a certain range, as the grain size increases, the surface roughness of the copper tube will also increase accordingly. However, when the grain size exceeds a certain range, the surface roughness begins to decrease. This is related to the abnormal growth of grains and the formation of recrystallization texture.
2. Recrystallization texture component: Recrystallization texture refers to a specific crystal structure formed during the processing of metal materials. The Gaussian texture component with "soft orientation" has a significant mitigating effect on the surface roughness of the copper tube. When the content of the Gaussian texture component increases, the surface roughness value of the copper tube will decrease and the surface quality will be improved.
Tips: Carbon steel pipe is made of steel ingots or solid round steel through perforation into capillary, and then made by hot rolling, cold rolling or cold drawing. Carbon steel pipe is the most common type of steel pipe. It is a steel pipe produced from carbon steel. Carbon steel pipes can be divided into seamless pipes, straight seam steel pipes and spiral steel pipes. Rolled seamless carbon steel pipe is made of steel ingot or solid round steel through perforation to make capillary, and then hot rolled, cold rolled or cold drawn.
