Carbon steel pipes come in various grades, each with specific properties and applications. The choice of grade depends on factors such as the intended use, operating conditions, and required mechanical properties. Here are some common grades of carbon steel pipes: ASTM A53/A53M: Grade A: This grade is typically used for non-pressure applications and is suitable for welding and forming operations. Grade B: Grade B is the most commonly used grade and is suitable for conveying fluids and gases under high pressure and temperature conditions. ASTM A106/A106M: Grade A: This grade is suitable for low-temperature applications and is commonly used in refineries and plants where corrosion resistance is not a concern. Grade B: Grade B is the most commonly used grade and is suitable for high-temperature and high-pressure applications such as steam, water, and oil transportation in refineries and plants. Grade C: This grade is commonly used for low-temperature applications and offers better impact properties than Grades A and B. ASTM A333/A333M: Grade 1: This grade is suitable for low-temperature applications down to -50�°F (-45�°C) and is commonly used in refineries, chemical plants, and power plants. Grade 3: Grade 3 offers good impact properties and is suitable for low-temperature applications down to -150�°F (-101�°C). Grade 6: Grade 6 is the most commonly used grade and offers excellent impact properties at low temperatures down to -50�°F (-45�°C). API 5L: Grade A: This grade is suitable for conveying low-pressure fluids and is commonly used in the transportation of natural gas and petroleum products. Grade B: Grade B is the most commonly used grade and is suitable for conveying fluids under high pressure and temperature conditions. X42, X52, X60, X65, X70, X80: These grades offer higher strength and are suitable for conveying fluids in demanding environments such as offshore drilling rigs and pipelines. ASTM A672/A672M: Grades A45, A50, A55, A60, A65, A70: These grades are electric-fusion-welded steel pipes suitable for high-pressure service at moderate temperatures. ASTM A691/A691M: Grades CM-65, CM-70, CM-75: These grades are electric-fusion-welded steel pipes suitable for high-pressure service at high temperatures. These are some of the commonly used grades of carbon steel pipes. Each grade has specific chemical composition and mechanical properties designed to meet various industry standards and applications. It's essential to consult relevant standards and specifications to select the appropriate grade for specific project requirements.