# US 2013/0199045 A1 · Equipment for use in corrosive environments and methods for forming thereof > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2013/0199045 A1 - Document ID: US20130199045A1 - Status: Published application - Kind: A1 - Application number: 13/763,137 - Filed: 2013-02-08 - Published: 2013-08-08 - Earliest claimed: 2012-02-08 - Assignees: Chevron U.S.A. Inc. - Inventors: Edwin Hall Niccolls; Grzegorz Jan Kusinski; David Lawrence Cooke - Web page: https://patentgrep.com/patent/US20130199045A1 ## CPC - B21B 3/00: Rolling materials of special alloys so far as the composition of the alloy requires or permits special rolling methods or sequences {; Rolling of aluminium, copper, zinc or other non-ferrous metals}(altering special metallurgical properties of alloys, other than structure consolidation or mechanical properties resulting therefrom C21D, C22F) - C22C 38/02: containing silicon - C22C 38/04: containing manganese - C22C 38/06: containing aluminium - C22C 38/20: with copper - C22C 38/22: with molybdenum or tungsten - C22C 38/24: with vanadium - C22C 38/26: with niobium or tantalum - C22C 38/34: with more than 1.5% by weight of silicon - Y10T 29/49616: Structural member making - Y10T 29/49634: Beam or girder - B21B: ROLLING OF METAL (auxiliary operations used in connection with metal-working operations covered in B21, see B21C; bending by rolling B21D; manufacture of particular objects, e.g. screws, wheels, rings, barrels, balls, by rolling B21H; pressure welding by means of a rolling mill B23K20/04) - C22C: ALLOYS (treatment of alloys C21D, C22F) - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract A method for forming structural equipment employed in sulfur containing environments such as oil refineries and the like. In one embodiment, the method comprises: providing a steel composition containing up to 0.35% of C, 0.30 to 3.5% Si, up to 1.2% Mo, up to 1.35% Mn, up to 5% Al, less than 12.0% Cr, balance of Fe and unavoidable impurities; forming a structural component conforming to prevailing industry standards with respect to design, fabrication, inspection and testing, metallurgical and mechanical properties. The structural equipment has a corrosion rate of less than 15 mpy. In one embodiment, the equipment is formed from a steel composition has a carbon equivalent of less than 0.63, requiring no post weld heat treatment (“PWHT”). In another embodiment, the CE is less than 0.45, requiring no preheat nor PWHT. ## Claims ### Claim 1 A method for forming a corrosion resistant structural equipment, the method comprising: providing a steel composition having chemical requirements as specified according to any of ASTM and API standards, and modified by adding at least 0.05% Si to the chemical requirements of Si, for a Si content ranging from 0.30 to 3.5% by weight; forming a structural equipment from the steel composition such that the structural equipment complies to at least one of the ASTM standards, API standards with respect to manufacture, dimensions and weight, mechanical properties, testing, and certification of the structural equipment; and wherein the structural equipment is suitable for containing hydrocarbons in sulfur containing environments operating at a temperature ranging from 400° F. to 1000° F., and wherein the structural equipment has a corrosion rate of 15 mpy or less upon exposure to hydrocarbons saturated with a gas stream containing 10% H2S and 90% nitrogen at 600° F. for 72 hours. ### Claim 2 (depends on 1) The method of claim 1, wherein the steel composition is modified for a Si content ranging from 0.30 to 1% by weight. ### Claim 3 (depends on 1) The method of claim 1, wherein the steel composition is modified by adding at least 0.25% Si to the Si chemical requirements specified in the standard. ### Claim 4 (depends on 1) The method of claim 1, for forming a structural equipment as a pressure vessel complying to at least one of ASME Boiler and Pressure Vessel Code, Pressure Equipment Directive of the European Union, Japanese Industrial Standard and Canadian Standard CSA B51 with respect to manufacture, dimensions and weight, mechanical properties, testing, and certification of the structural equipment. ### Claim 5 (depends on 1) The method of claim 1, for forming a structural equipment as a pipe for high temperature applications complying to at least one of ASTM A106 and ASTM A36 standards with respect to manufacture, dimensions and weight, mechanical properties, testing, and certification of the pipe. ### Claim 6 (depends on 1) The method of claim 1, wherein providing a steel composition having chemical requirements as specified according to any of ASTM and API standards comprises providing an alloy steel composition having chemical requirements as specified according to ASTM A335 Grade P-5 standard with 4.0 to 6.0% Cr, and modified by adding at least 0.25% Si to the chemical requirements for a Si content ranging from 0.75 to 2.5% by weight, and wherein wherein the structural equipment is suitable for applications having exposure to hydrocarbons containing at least 0.2 wt. % sulfur for at least 30% of the time, and operating at a temperature ranging from 400° F. to 1000° F., and wherein the structural equipment has a corrosion rate of 10 mpy or less upon exposure to hydrocarbons saturated with a gas stream containing 10% H2S and 90% nitrogen at 600° F. for 72 hours. ### Claim 7 (depends on 1) The method of claim 1, wherein providing a steel composition having chemical requirements as specified according to any of ASTM and API standards comprises providing an alloy steel composition having chemical requirements as specified according to ASTM A335 Grade P-9 standard with 8.0 to 10.0% Cr, and modified by adding at least 0.25% Si to the chemical requirements for a Si content ranging from 0.75 to 2.5% by weight, and wherein wherein the structural equipment is suitable for applications having exposure to hydrocarbons containing at least 0.2 wt. % sulfur for at least 30% of the time, and operating at a temperature ranging from 400° F. to 1000° F., and wherein the structural equipment has a corrosion rate of 5 mpy or less upon exposure to hydrocarbons saturated with a gas stream containing 10% H2S and 90% nitrogen at 600° F. for 72 hours. ### Claim 8 (depends on 7) The method of claim 7, wherein the an alloy steel composition is modified for a Si content ranging from 0.5 to 1.5% by weight. ### Claim 9 (depends on 7) The method of claim 7, wherein the an alloy steel composition is further modified for an Al content ranging from 0.9 to 2% by weight. ### Claim 10 (depends on 1) The method of claim 1, wherein providing a steel composition having chemical requirements as specified according to any of ASTM and API standards comprises providing a steel composition having a sufficient chemistry for the composition to have a CE of less than 0.45, requiring no preheat and no post weld heat treatment after welding. ### Claim 11 (depends on 1) The method of claim 1, wherein providing a steel composition having chemical requirements as specified according to any of ASTM and API standards comprises providing a carbon steel composition having Si chemical requirements according to any of ASTM A537, ASTM A106 and ASTM A36 standards and modified by adding at least 0.05% Si to the Si chemical requirements specified in the standard. ### Claim 12 (depends on 1) The method of claim 1, wherein providing a steel composition having chemical requirements as specified according to any of ASTM and API standards comprises providing a carbon steel composition having Si chemical requirements according to any of ASTM A537, ASTM A106 and ASTM A36 standards and modified by adding at least 0.05% Si to the Si chemical requirements specified in the standard for a composition having as components in weight: up to 0.35% of C; 0.30 to 3.5% Si; up to 1.2% Mo; up to 1.35% Mn; up to 5% Al; less than 12.0% Cr; balance of Fe and unavoidable impurities. ### Claim 13 (depends on 1) The method of claim 1, wherein the method is for making an as-welded steel pipe, and wherein forming a structural equipment from the steel composition comprises: forming a cast steel slab from the steel composition, the steel composition has as components in weight: up to 0.35% of C; from 0.30 to 3.5% Si; up to 0.15% Mo; up to 1.35% Mn; up to 5% Al; one or more elements selected from Cr, Cu, and Ni in an amount of up to 0.4% each; a total concentration of Cr, Cu, Mo, Ni, and V of up to 1%; balance of Fe and unavoidable impurities; heating the steel slab to a temperature in excess of 2000° F.; rolling a heated steel slab in a rolling mill to obtain a skelp having a desired thickness; forming the skelp into a pipe having two side edges positioned in contact with one another; and welding the two side edges together to form an as-welded pipe; wherein the as-welded pipe complies to at least one of ASTM and API standards with respect to manufacture, dimensions and weight, mechanical properties, testing, and certification; wherein the as-welded pipe is for containing hydrocarbons in sulfur-containing environments operating at a temperature ranging from 400° F. to 1000° F.; wherein upon exposure to hydrocarbons saturated with a gas stream containing 10% H2S and 90% nitrogen at 600° F. for 72 hours, the pipe has a corrosion rate of less than 15 mpy. ### Claim 14 (depends on 13) The method of claim 13 for making an as-welded steel pipe, wherein the steel composition contains 0.3% to 1% Si by weight. ### Claim 15 (depends on 13) The method of claim 13 for making an as-welded steel pipe, wherein the steel composition has a CE of less than 0.45. ### Claim 16 (depends on 1) The method of claim 1, wherein the method is for making an as-welded steel pipe complying to any of ASTM A537, ASTM A106 and ASTM A36 standards with respect to manufacture, dimensions and weight, mechanical properties, testing, and certification; wherein the as-welded pipe is containing hydrocarbons in sulfur-containing environments operating at a temperature ranging from 400° F. to 1000° F.; and wherein upon exposure to hydrocarbons saturated with a gas stream containing 10% H2S and 90% nitrogen at 600° F. for 72 hours, the pipe has a corrosion rate of less than 15 mpy. ### Claim 17 (depends on 16) The method of claim 16, wherein the steel composition has a CE of less than 0.45. ### Claim 18 (depends on 16) The method of claim 16, wherein the steel composition has a CE of greater than 0.45 and less than 0.63. ### Claim 19 (depends on 1) The method of claim 1, wherein the method is for making a seamless steel pipe, and wherein forming a structural equipment from the steel composition comprises: forming a billet from the steel composition, the steel composition having as components in weight: up to 0.35% of C; from 0.30 to 3.5% Si; up to 0.15% Mo; up to 1.35% Mn; up to 5% Al; one or more elements selected from Cr, Cu, and Ni in an amount of up to 0.4% each; a total concentration of Cr, Cu, Mo, Ni, and V of up to 1%; balance of Fe and unavoidable impurities; subjecting the billet to a piercing operation to form a hollow shell; rolling the hollow shell into a seamless steel pipe; wherein the seamless pipe complies to at least one of ASTM and API standards with respect to manufacture, dimensions and weight, mechanical properties, testing, and certification; and wherein the seamless steel pipe is for use in sulfur-containing environments, and wherein upon exposure to hydrocarbons saturated with a gas stream containing 10% H2S and 90% nitrogen at 600° F. for 72 hours, the pipe has a corrosion rate of less than 15 mpy. ### Claim 20 (depends on 1) The method of claim 1, wherein the method is for making an as-welded steel pipe, and wherein forming a structural equipment from the steel composition comprises: forming a cast steel slab from the steel composition; heating the steel slab to a temperature in excess of 2000° F.; rolling a heated steel slab in a rolling mill to obtain a skelp having a desired thickness; forming the skelp into a pipe having two side edges positioned in contact with one another; and welding the two side edges together to form an as-welded pipe; wherein the as-welded pipe complies to any of ASTM A537, ASTM A106 and ASTM A36 standards with respect to manufacture, dimensions and weight, mechanical properties, testing, and certification; wherein the as-welded pipe is for containing hydrocarbons in sulfur-containing environments operating at a temperature ranging from 400° F. to 1000° F.; and wherein upon exposure to hydrocarbons saturated with a gas stream containing 10% H2S and 90% nitrogen at 600° F. for 72 hours, the pipe has a corrosion rate of less than 15 mpy. ### Claim 21 (depends on 1) The method of claim 1, wherein the method is for making an as-welded steel pipe, and wherein forming a structural equipment from the steel composition comprises: forming a billet from the steel composition; subjecting the billet to a piercing operation to form a hollow shell; rolling the hollow shell into a seamless steel pipe; wherein the seamless pipe complies to at least one of ASTM and API standards with respect to manufacture, dimensions and weight, mechanical properties, testing, and certification; and wherein the seamless steel pipe is for use in sulfur-containing environments, and wherein upon exposure to hydrocarbons saturated with a gas stream containing 10% H2S and 90% nitrogen at 600° F. for 72 hours, the pipe has a corrosion rate of less than 15 mpy.