The invention discloses a solder wire for submerged arc welding of X100 pipeline steel, which consists of the following components in percentage by weight: 0.03 to 0.06 percent of C, 0.1 to 0.3 percent of Si, 1.0 to 2.0 percent of Mn, 0.7 to 1.0 percent of Ni, 0.3 to 0.6 percent of Mo, 0.3 to 0.6 percent of Cr, 0.01 to 0.04 percent of Nb, 0.1 to 0.3 percent of Ti, 0.0015 to 0.005 percent of B, 0.1 to 0.3 percent of Cu, 0.1 to 0.3 percent of Ce, 0.01 to 0.05 percent of Al, less than 0.01 percent of S, less than 0.01 percent of P and the balance of Fe. The solder wire has the advantages of high strength of welding lines, good impact property and the like. The invention also discloses a preparation method for the solder wire, which comprises the following steps of: smelting Fe, Nb and the like in a vacuum induction furnace, raising the temperature to 1,540 DEG C, keeping the temperature, and after the molten steel is calm, cooling and exhausting; refining, reducing temperature, performing fine adjustment on Ti content, introducing a protective gas Ar before tapping, simultaneously adding components such as Mn, Fe and the like, stirring, tapping and casting to obtain steel ingots; and performing subsequent forging, rolling and drawing on the steel ingots, and finally obtain solder wires. The preparation method for the solder wire is stable in smelting process and easy to implement; and the product has good properties.

Solder wire for submerged arc welding of X100 pipeline steel and preparation method thereof

The invention discloses a multiple-wire submerged arc welding process suitable for thick-wall straight-seam steel pipes X70. According to the process, by means of the JCOE forming process, a steel pate is made into a steel pipe, and a pipe seam is closed the steel pipe; the steel pipe is pre-welded by high-power mixed gas shielded welding to obtain a continuous, standard and stable-quality pre-weld; internal and external welds of the steel pipe are welded by automatic submerged arc welding with four wires for internal welding and five wires for external welding; the internal welding wires and the external welding wires are all H08C wires 4.0mm in diameter; flux 998N is used. The problem that a heat affected zone of a welded joint is softened and embrittled under the condition of multiple-wire common-path High heat input welding is solved; the welded joint of the thick-wall straight-seam steel pipe X70, manufacture by the process, has good low-temperature toughness and fracture toughness and good crack resistance and void resistance, and meets the special requirements on multiple comprehensive performances of the welded joints of deep-sea oil and gas transmission pipelines for deep-sea services, such as high toughness, high plasticity, fatigue resistance and corrosion resistance.

Multiple-wire submerged arc welding process suitable for thick-wall straight-seam steel pipes X70

The invention provides an equal-strength matching submerged arc welding method for strong-strength P690QL1 steel. The method comprises the following steps of (1) adopting an asymmetric X-shaped groove as a submerged arc welding groove, and adopting an S3Ni2 welding wire and an SA FB155AC welding flux as submerged arc welding materials; (2) preheating a P690QL1 steel plate; (3) adopting direct current reverse polarity, wherein current is 500 to 550A, voltage is 28 to 32V, welding speed is 35 to 40cm/min, linear energy is 20 to 32kJ/cm, and the baking temperature of the welding flux is 350 DEG C*2h; (4) performing dehydrogenation heat treatment after welding; and (5) performing after-welding SR (stress relieving) heat treatment after a weld joint passes nondestructive detection. According to the submerged arc welding method, high toughness of a welded joint formed by the automatic strong-strength steel submerged arc welding of the P690QL1 steel at -20 DEG C is achieved after the welded joint is subjected to the SR treatment, and a requirement on the strength matching of the welded joint and base metal is met.

Equal-strength matching submerged arc welding method for strong-strength P690QL1 steel

The invention relates to excellent-toughness large-wall-thickness X80 steel for low-temperature stations, and a manufacturing method thereof, belonging to the technical field of low-carbon microalloy steel. The steel for stations comprises the following elements in percentage by weight: 0.035-0.065% of C, 0.10-0.35% of Si, 1.60-1.85% of Mn, no more than 0.015% of P, no more than 0.003% of S, 0.05-0.09% of Nb, no more than of 0.06% of V, 0.010-0.020% of Ti, 0.15-0.50% of Ni, no more than 0.50% of Cr, no more than 0.50% of Mo, 0.010-0.040% of Al, 0.40-0.50% of Ceq, 0.15-0.21% of Pcm, and the balance of Fe and inevitable impurities. The manufacturing method comprises the following steps sequentially: blast-furnace iron melting, pre-desulfurization of molten iron, converter smelting, LF+RH refining, continuous blank casting, blank heating, rolling of a 4300 rolling machine, ACC fast cooling, stack cooling, sampling and inspection, storage and transportation. The excellent-toughness large-wall-thickness X80 steel for low-temperature stations has the advantages that the maximum thickness of a steel plate is up to 33mm, so that not only can the comprehensive performance of the excellent-toughness large-wall-thickness X80 steel for low-temperature stations meet the requirement, but also the excellent-toughness large-wall-thickness X80 steel for low-temperature stations has excellent low-temperature toughness.

Excellent-toughness large-wall-thickness X80 steel for low-temperature stations, and manufacturing method thereof

The invention discloses a high-plasticity longitudinal submerged arc welding tube for an X70 steel-grade thick-wall deep-sea pipeline and a manufacturing method of the high-plasticity longitudinal submerged arc welding tube The high-plasticity longitudinal submerged arc welding tube comprises the following ingredients in percentage by mass: 004-007 percent of C, 020-035 percent of Si, 140-170 percent of Mn, smaller than or equal to 0015 percent of P, smaller than or equal to 0003 percent of S, 010-030 percent of Ni, 010-030 percent of Cr, smaller than or equal to 035 percent of Cu, 010-030 percent of Mo, 004-007 percent of Nb, smaller than or equal to 006 percent of V, smaller than or equal to 002 percent of Ti, smaller than or equal to 004 percent of Al, smaller than or equal to 0005 percent of N, smaller than or equal to 00005 percent of B and the balance of iron and unavoidable impurities, wherein the ratio of Al to N is larger than or equal to 3, and the percentage sum of Nb, V and Ti is smaller than or equal to 012% The high-plasticity longitudinal submerged arc welding tube disclosed by the invention can be used for satisfying specific requirements of deep-sea oil gas conveying pipelines in the aspects such as conquassation resistance, high plasticity, fatigue resistance, seawater corrosion resistance and high dimensional accuracy

High-plasticity longitudinal submerged arc welding tube for X70 thick-wall deep-sea pipeline and manufacturing method of high-plasticity longitudinal submerged arc welding tube

The invention discloses an X80-level straight seam submerged-arc welded pipe with hydrogen sulfide stress corrosion resistance as well as a manufacturing method thereof. The straight seam submerged-arc welded pipe comprises a welding seam and a welded pipe body, and is characterized in that the welded pipe body consists of the following elements in percent by mass: not greater than 0.04% of C, 0.20%-0.40% of Si, 1.20%-1.80% of Mn, not greater than 0.008% of P, not greater than 0.002% of S, 0.10%-0.30% of Ni, not greater than 0.15% of Cr, not greater than 0.15% of Cu, 0.01%-0.10% of Nb, 0.01%-0.10% of Ti, 0.10%-0.30% of Mo, 0.04%-0.10% of Al, not greater than 0.0005% of B, not greater than 0.002% of Ca, and the balance of Fe and inevitable impurities. According to the X80-level straight seam submerged-arc welded pipe and the manufacturing method thereof disclosed by the invention, the X80 straight seam submerged-arc welded pipe disclosed by the invention has good strength, toughness, welding performance, ductility and corrosion resistance through reasonably deploying and controlling material components, a manufacturing process, a manufacturing technology and subsequent processing. Besides, high-pressure large-flow conveying requirements of oil gas under an acidic environment are satisfied.

X80-level straight seam submerged-arc welded pipe with hydrogen sulfide stress corrosion resistance as well as manufacturing method thereof

The invention relates to a high-strength submerged-arc welding wire for pipe line steel, which comprises the following chemical components: 0.02-0.10wt% of C, 0.10-0.60wt% of Si, 1.50-2.50wt% of Mn, less than 0.010wt% of P, less than 0.010wt% of S, 0.7-3.0wt% of NiO, 0.05-0.2wt% of Ti, 0.20-0.60wt% of Mo, 0.003-0.02wt% of B and the balance Fe. The high-strength submerged-arc welding wire of the invention can obtain optimal weld strong toughness by matching with the BGSJ101H1 flux and other special fluxes for welding of pipe line steel; the tensile strength sigma b of the weld metal is greater than or equal to 760Mpa; the ballistic work Akv of the weld metal at -10 DEG C is greater than or equal to 120J; and the high-strength submerged-arc welding wire is suitable for high-speed submerged-arc welding of X100 ultra-high grade pipe line steel plates for conveying pipe lines of high pressure oil or high pressure gas.

High-strength submerged-arc welding wire for pipe line steel

The invention discloses a high-strength water riser main-pipe with excellent anti-fatigue performance and a manufacturing method thereof. the water riser main-pipe comprises the following chemical components: by weight, 0.04-0.08% of C, 0.15-0.35% of Si, 1.55-1.85% of Mn, P being less than or equal to 0.015%, S being less than or equal to 0.003%, Ni being less than or equal to 0.30%, Cr being less than or equal to 0.30%, Cu being less than or equal to 0.25%, Mo being less than or equal to 0.25%, 0.02-0.060% of Nb, V being less than or equal to 0.06%, 0.008-0.06% of Ti, 0.010-0.040% of Al and N being less than or equal to 0.008%, Al/N being greater than or equal to 3, Ni+Cu+Mo+Cr being less than or equal to 0.70%, and Nb+V+Ti being less than or equal to 0.12%. Carbon equivalent Ceq is less than or equal to 0.45, and cold crack coefficient Pcm is less than or equal to 0.23. A microstructure is a composite fine-grain structure of acicular ferrite+bainite. The invention provides an X80 high-strength water riser main-pipe with fatigue resistance and high dimensional accuracy. The water riser main-pipe is characterized by having excellent comprehensive performance such as plasticity, low-temperature toughness, fracture resistance, corrosion resistance and the like.

High-strength water riser main-pipe with excellent anti-fatigue performance and manufacturing method thereof

The invention discloses a high-strength medium-caliber thick-wall subsea pipeline and its manufacturing method The subsea pipeline comprises the following chemical components: by weight, 004-008% of C, 020-035% of Si, 140-165% of Mn, P being less than or equal to 0015%, S being less than or equal to 0003%, Ni being less than or equal to 030%, Cr being less than or equal to 010-030%, Cu being less than or equal to 025%, Mo being less than or equal to 035%, 002-0060% of Nb, V being less than or equal to 006%, 0008-0030% of Ti, 0015-0050% of Al, N being less than or equal to 001%, B being less than or equal to 00005%, Al/N being greater than or equal to 3, Nb+V+Ti being less than or equal to 012%, and the balance being iron and unavoidable impurities Carbon equivalent Ceq is less than or equal to 043, and cold crack coefficient Pcm is less than or equal to 022 The X70 steel-grade medium-caliber thick-wall steel tube for a subsea pipeline has comprehensive performance such as longitudinal and transverse strength, toughness, tube and weld-joint breaking tenacity, decay resistance and the like

Zhao Hongbo

Papers

X80-level straight seam submerged-arc welded pipe with hydrogen sulfide stress corrosion resistance as well as manufacturing method thereof

Multiple-wire submerged arc welding process suitable for thick-wall straight-seam steel pipes X70

High-strength submerged-arc welding wire for pipe line steel

High-strength water riser main-pipe with excellent anti-fatigue performance and manufacturing method thereof

High-strength medium-caliber thick-wall subsea pipeline and its manufacturing method