In high-pressure industrial fields such as chemical engineering, energy, and pharmaceuticals, the stress cracking resistance of pipeline materials is directly related to production safety and system lifespan. Traditional plastic pipelines often suffer from molecular chain breakage under high-temperature and high-pressure environments, leading to leaks or even explosions. However, Sinopec's domestic PB-1, with its breakthrough stress cracking resistance — featuring a stress cracking time of over 1,000 hours at 80℃C and 4MPa pressure, and a design stress reaching the highest level among similar pipes — provides a reliable material solution for high-pressure industrial scenarios.

"Crack-Resistant Endurance" in Extreme Environments

Stress cracking resistance is a core indicator of a material's ability to maintain integrity under sustained stress and environmental erosion. Under the dual effects of 80℃C hot water and 4MPa high pressure, most plastic pipes develop cracks within hundreds of hours, while Sinopec PB-1 can remain intact for over 1,000 hours. This data far exceeds the industry standard threshold (400 hours specified in GB/T 1842-2008) and even reaches 1.5 times the international advanced level.

This exceptional performance stems from PB-1's unique molecular structure: the dense molecular arrangement formed by high crystallinity (48%-55%), combined with the stress-dispersing properties of long branched chains, prevents microcracks from forming under sustained high pressure. Experimental data shows that under the same test conditions, PPR pipes only have a stress cracking time of 300-500 hours, and PE pipes around 600 hours, while Sinopec PB-1 significantly outperforms them, serving as a "safety barrier" for high-pressure systems.

Precise Adaptation to High-Pressure Industrial Scenarios

In industrial production, many scenarios impose extreme requirements on the stress cracking resistance of pipelines: solvent delivery pipelines in the chemical industry must withstand long-term exposure to corrosive media and high pressure; geothermal transmission pipes in the energy sector need to cope with the dual challenges of hot water above 90℃C and formation pressure; pure water pipelines in the pharmaceutical industry must remain leak-free during high-pressure sterilization cycles.

Sinopec PB-1 stands out as the ideal choice for these scenarios with three core advantages:

· Ultra-long crack-resistant lifespan: It can operate stably for over 1,000 hours under 80℃C and 4MPa conditions. Calculated based on 24-hour daily operation of industrial systems, the single maintenance cycle can be extended to over 40 days, reducing unplanned shutdowns;

· High design stress: The design stress of similar pipes is generally 1.0-1.6MPa (at 20℃C), while Sinopec PB-1 can reach 2.5MPa, meaning the pipe wall thickness can be reduced by 30% under the same pressure, lowering material consumption and installation load;

· Excellent medium compatibility: It has superior resistance to industrial fluids such as acids, alkalis, and organic solvents. After soaking in an 80℃C solution containing 5% sulfuric acid for 30 days, the retention rate of mechanical properties still reaches over 90%.

Currently, Sinopec PB-1 pipes have been applied in an oily wastewater transmission system of an oilfield in Xinjiang (operating pressure 3.5MPa, temperature 75℃C). After 18 months of operation, no stress cracking has occurred, and the maintenance cycle has been doubled compared to traditional PE pipes; in the solvent circulation pipeline of a chemical plant in Jiangsu, its crack resistance has helped the enterprise achieve a continuous production cycle exceeding 120 days, setting an industry record.

"High-Pressure Gene" Forged by Independent Technology

This stress cracking resistance that surpasses international standards originates from Sinopec's original polymerization process and material modification technology. By regulating the regularity and branching structure of polybutene-1 molecular chains, combined with a dedicated antioxidant system, the stability of molecular chains of the material under high temperature and pressure has been significantly improved. As the core achievement of China's first 3,000-ton/year high isotactic polybutene-1 industrial demonstration plant, its production technology is completely independently controllable, breaking the technical monopoly of foreign brands in the field of high-pressure weather-resistant materials.

Compared with similar imported products, Sinopec PB-1 has a 15% longer stress cracking time under 80℃C and 4MPa conditions, while the cost is reduced by 18%, achieving the dual breakthrough of "leading performance and optimized cost". More importantly, in response to the diverse needs of domestic industrial scenarios, Sinopec can provide customized formulas — for example, the enhanced PB-1 developed for ultra-high pressure scenarios (above 6MPa) can further extend the crack resistance time to 1,500 hours through modification with nano-calcium carbonate.