Manufacturing method for X90 pipeline steel longitudinal submerged arc welding pipe

The invention discloses a manufacturing method for X90 pipeline steel longitudinal submerged arc welding pipe, the mass percent of the X90 pipeline steel consisting of: C 0.04-0.08%, Mn1.60-2.0%, Si 0.15-0.45%, S<=0.006%, P<=0.010%, Ni 0.20-0.50%, Mo 0.10-0.30%, Ti 0.010-0.020%, Al 0.015-0.050%, Nb 0.05-0.10%, V<= 0.05%, N <= 0.01%, Cu 0.10-0.30%, Cr <= 0.35%, B <= 0.004%, the rest is Fe, wherein Ceq <= 0.50, Pcm<= 0.25; the inside welding and outside welding adopt 4-wire submerged arc automatic welding. The welding pipe of the invention has advantages of tenacious welding joints and uniform performance.