Correctly selecting and using 15CrMoG boiler steel pipes requires attention to several key stages: selection, installation, operation, and maintenance.
First, what are the key considerations for selecting 15CrMoG boiler steel pipes?
(1) Based on operating parameters.
Accurately consider parameters such as boiler operating temperature, pressure, and medium composition. If the operating temperature is consistently between 500-550℃, the pressure is in the medium-high pressure range, and the medium is not highly corrosive, 15CrMoG boiler steel pipes are an ideal choice. This is because their alloy composition ensures creep resistance and oxidation resistance within this temperature range, maintaining the strength and stability of the steel pipe and resisting steam pressure. If the operating temperature exceeds 550℃, higher-grade heat-resistant alloy steel pipes must be evaluated.
(2) Matching Steel Pipe Diameter and Wall Thickness: Determine the appropriate steel pipe diameter based on the steam flow requirements. Use the flow calculation formula to calculate the ideal 15CrMoG boiler steel pipe diameter that can meet the conveying capacity. Then, according to the pressure value to be borne, refer to the corresponding standard for pressure-resistant steel pipe wall thickness to select an appropriate steel pipe wall thickness to ensure that the steel pipe can withstand the internal pressure and prevent the risk of bursting.
(3) Quality Control: Prioritize products produced by reputable large steel mills. Check whether the products come with complete quality certification documents, such as material analysis reports, mechanical property test reports, and non-destructive testing results, to ensure that the initial quality of the 15CrMoG boiler steel pipe meets the standards.
Second, what should be noted during the installation of 15CrMoG boiler steel pipes?
(1) Pre-treatment of steel pipes.
Before installation, a comprehensive inspection of the 15CrMoG boiler steel pipes should be conducted to check for defects such as cracks, sand holes, and heavy scale on the surface; clean the debris, rust, and oil stains inside the 15CrMoG boiler steel pipes to maintain cleanliness; perform necessary straightening of the 15CrMoG boiler steel pipes to ensure that the straightness meets the installation requirements and reduce the potential for stress concentration later.
(2) Welding points.
Because it contains alloying elements, preheating is required in the range of 150-200℃ before welding to slow down the welding cooling rate and avoid the formation of hardened structures. Use matching heat-resistant steel welding rods, such as R307 welding rods. Strictly control the current, voltage, and welding speed during the welding process. Immediately after welding, perform tempering treatment at 680-720℃ to eliminate welding stress and optimize the performance of the weld and heat-affected zone.
(3) Rationality of Installation Layout.
The design of the 15CrMoG boiler steel pipe routing should be scientific, avoiding sharp bends and frequent changes in direction to reduce unnecessary stress; based on the principle of thermal expansion and contraction, reasonable space should be reserved for steel pipe expansion and contraction, and expansion joints, bend compensators, and other components should be added to prevent thermal stress from damaging the steel pipe.
Third, what should be paid attention to during the operation and maintenance of 15CrMoG boiler steel pipe?
(1) Start-up and Shutdown Procedures: When starting the boiler, the temperature and pressure should be increased slowly to give the steel pipe a buffer time to adapt to the temperature and pressure changes, such as controlling the heating rate at 12℃/min; when shutting down, the temperature and pressure should be decreased slowly to avoid thermal shock.
(2) Regular Inspection: During operation, the appearance of the 15CrMoG boiler steel pipe should be checked regularly for deformation, leakage, and corrosion; the wall thickness of the 15CrMoG boiler steel pipe should be monitored, and the initial wall thickness should be compared with equipment such as ultrasonic thickness gauges to predict the degree of corrosion and wear; welds in key parts should be inspected regularly to check for potential welding defects.
(3) Water quality control: Given that boiler steel pipes are in contact with steam and water for a long time, it is necessary to ensure that the feed water quality is excellent, remove impurities, dissolved oxygen, and hardness ions from the water, reduce the risk of scaling and corrosion, and extend the service life of 15CrMoG boiler steel pipes.
Post time: Jan-20-2026