What role does petroleum cracking pipe play in the petroleum industry

2025-09-08 09:54:23

　　As a key equipment component in the petroleum industry, petroleum cracking pipes play a role throughout the entire process of crude oil processing, directly affecting refining efficiency, safety, and economic benefits. This special material seamless steel pipe exhibits irreplaceable performance in high temperature, high pressure, and corrosive environments, becoming one of the core components of modern refining equipment.

　　1、 Technical characteristics and manufacturing requirements of petroleum cracking pipes

　　Petroleum cracking pipes are usually made of chromium molybdenum alloy steel (such as 15CrMo, 12Cr1MoV, etc.) or austenitic stainless steel, which must meet three core indicators: firstly, they can maintain strength and excellent creep resistance in high temperature environments above 550 ℃; Secondly, it needs to withstand the corrosion of corrosive media such as hydrogen sulfide and cyclic acid, and some high-end products adopt lining anti-corrosion coating technology; Finally, the blasting pressure must reach at least three times the working pressure to ensure safety. Taking the Φ 219 × 18mm cracking pipe used in a large refinery as an example, its high-temperature endurance strength can reach 80MPa (550 ℃/100000 hours), which is much higher than the 35MPa standard of ordinary transportation pipelines.

　　The manufacturing process adopts a combination of hot rolling and cold drawing, and Baosteel and other enterprises have achieved precision control of wall thickness tolerance within ± 5%. The latest developed TP347HFC stainless steel cracking tube has extended its service life to 1.8 times that of traditional materials through grain boundary engineering technology. This technology has been successfully applied in the Sinopec Zhenhai Refining and Chemical Phase II project.

　　2、 Specific application scenarios in refining equipment

　　1. Catalytic cracking unit: In the reactor regenerator system, the cracking tubes need to withstand high temperatures of 720 ℃ and catalyst erosion. After using a double-layer structure cracking tube in a certain refinery, the wear rate decreased from 1.2mm per year to 0.3mm. A special internal spiral structure cracking tube was used in the riser reactor, which increased the oil contact efficiency by 15%.

　　2. Hydrocracking unit: In a 15MPa hydrogen partial pressure environment, resistance to hydrogen embrittlement becomes crucial. After a refinery in Shanghai adopted 12Cr2Mo1R steel grade cracking pipes, the equipment maintenance cycle was extended from 2 years to 4 years. The cracking tubes used in high-pressure heat exchangers need to meet the alternating working conditions of -196 ℃ deep cooling and 450 ℃ high temperature simultaneously.

　　3. Delayed coking unit: The feed pipeline of the coke tower is facing high temperature of 500 ℃ and coke powder erosion. The latest developed nanocrystalline coating cracking tube has reduced erosion rate by 40% and significantly reduced unplanned downtime in the application of Maoming Petrochemical.

　　3、 Improving the quality and efficiency of refining processes

　　The use of high-performance cracking tubes can directly improve economic benefits. The data shows that:

　　-Increasing thermal intensity by 10% can increase cracking depth by 1.2 percentage points

　　-Improvement in corrosion resistance can increase the yield of distillate oil by 0.8-1.5%

　　-After replacing a new type of cracking pipe in a 10 million ton refinery, unplanned shutdowns were reduced by 7 days annually, resulting in an increase of over 200 million yuan in revenue

　　In terms of environmental protection, after using a new type of cracking pipe, a refining enterprise in Shandong Province reduced the occurrence of equipment leakage by 80% and VOCs emissions by 35%. Especially in the residue hydroprocessing stage, high-precision cracking tubes improve reaction uniformity and increase sulfur conversion rate from 92% to 96%.