Stainless steel seamless pipes generally meet the requirements of various harsh working environments through material selection and process optimization, and are the preferred solution for modern industrial pipeline systems.
Stainless steel seamless pipes have a wide range of applications in the petrochemical industry, mainly due to their excellent corrosion resistance, high strength, high temperature and high pressure resistance, and good processing performance.
Here are its specific application areas and advantages:
1. Main application scenarios of seamless pipes
(1) High temperature and high pressure environment
-Refinery unit: a high-temperature and high-pressure pipeline system used in atmospheric and vacuum distillation, catalytic cracking, hydrocracking and other units, such as reactor inlet and outlet pipelines, heating furnace tubes, etc.
-Ethylene cracking unit: In high-temperature (up to 1000 ℃ or above) environments such as cracking furnaces and rapid cooling systems, stainless steel seamless pipes (such as 310S and 347H materials) can resist high-temperature oxidation and carburizing problems.
(2) Transport of corrosive media
-Acidic environment: Oil and gas extraction in corrosive media such as hydrogen sulfide (H ? S), carbon dioxide (CO ?), chloride, etc
Austenitic stainless steel (such as 316L, 904L) or duplex steel (such as 2205) can effectively resist pitting corrosion and stress corrosion in processes such as natural gas purification and sulfur recovery.
-Acid alkali storage and transportation: a pipeline system used for transporting chemicals such as concentrated sulfuric acid, nitric acid, alkaline solution, etc.
(3) Heat exchange equipment
-Tube bundles of heat exchangers: Stainless steel seamless tubes (such as 304, 316) are widely used in heat exchange equipment such as condensers and reboilers due to their corrosion resistance and thermal conductivity.
(4) Instrumentation and Control System
-Instrument pipeline: Small caliber stainless steel seamlesstubings (such as 1/4 "~2") are used as impulse pipes for pressure gauges, flow meters, and other instruments to ensure measurement accuracy and safety.
(5) Other key equipment
-Reactor internals: used as catalyst delivery pipes, internal cooling pipes, etc.
-LNG low-temperature pipeline: Austenitic stainless steel (such as 304L, 316L) maintains good toughness at low temperatures and is suitable for transporting liquefied natural gas (-162 ℃).
2. Commonly used stainless steel materials
-Austenitic stainless steel:
-304/304L: Universal type, used in general corrosive environments.
-316/316L: containing molybdenum, resistant to chloride corrosion, suitable for seawater or high salt environments.
-321/347H: containing titanium or niobium, resistant to high temperature oxidation, used for heating furnace tubes.
-Dual phase stainless steel (such as 2205, 2507): combines high strength and resistance to chloride stress corrosion, suitable for harsh environments (such as subsea pipelines).
-High nickel alloys (such as Inconel 625, 825): used in extreme corrosion conditions (such as high concentration acidic oil and gas fields).
3. Core advantages of seamless pipes
-Corrosion resistance: Resist common electrochemical corrosion, intergranular corrosion, and stress corrosion cracking in the petrochemical industry.
-High strength: Seamless process without any weak points in the weld seam, with better pressure bearing capacity than welded pipes.
-Cleanliness: Smooth inner wall, not prone to scaling, suitable for high-purity media (such as pharmaceutical intermediate production).
-Longevity: Reduce downtime maintenance frequency and lower overall lifecycle costs.
4. Industry standards and certifications
-International standards: ASTM A312 (austenitic stainless steel pipe), ASTM A790 (duplex seamless steel pipe), API 5LC (corrosion-resistant alloy pipeline pipe).
-Domestic standards: GB/T 14976 (Seamless Stainless Steel Pipes for Fluid Transport), GB 9948 (Seamless Pipes for Petroleum Cracking).
-Special requirements: Must pass tests such as sulfide stress corrosion (SSC) and intergranular corrosion (GB/T 4334).
5. Development trend of seamless pipes
-Material upgrade: The use of high alloying (such as super austenitic steel 654SMO) can cope with more demanding environments.
-Lightweight design: By optimizing the wall thickness of the pipe, material consumption can be reduced.
-Intelligent monitoring: Combining corrosion sensors to monitor the status of pipelines in real time.
So stainless steel seamless pipe is a key material in the petrochemical industry, especially irreplaceable in high temperature, high pressure, and corrosive environments. With the development of petrochemical processes towards high efficiency and environmental protection, the demand for high-performance stainless steel seamless pipes will continue to increase. Customers need to comprehensively consider factors such as medium characteristics, temperature, pressure, and cost when selecting, and strictly follow relevant standards.
