A design calculation problem for integrate reinforced straight tee in major tapping

Combined with problems found in execution of SY 0518-92 "Design Regulations for Butt Welding Steel Fittings in Oil & Gas Pipeline" and design experience, puts forward that following attention shall be paid to in speeding design and ensure design quality; (1) value taking method of weld coefficient; (2) value taking method of increment Δ₁ and Δ₂; (3) weakening calculation problem of factor η.