9results about How to "Improve crack arrest performance" patented technology

The embodiment of the invention provides a conveying pipeline crack arrestor and a crack arresting method. The conveying pipeline crack arrestor comprises a base and a pipe cover, the base is detachably covered with the pipe cover, a cavity for containing a conveying pipeline is formed by the pipe cover and the base, the pipe cover is provided with a glue injection opening communicated with the cavity, and the glue injection opening is communicated with the pipe cover. And a glue solution bearing area is formed among the inner wall surface of the pipe cover, the inner wall surface of the base and the conveying pipeline. The injected glue solution is injected into the cavity through the glue injection opening, flows downwards under the action of gravity and fills the glue solution bearing area, the problem that the glue solution drips downwards along with the surface of the pipeline can be prevented, the glue solution is solidified in the crack area of the conveying pipeline, and the crack arrest effect is achieved. Therefore, the conveying pipeline crack arrestor has the advantages of being good in crack arresting effect and capable of reducing glue solution waste.

The invention discloses a hot rolling process method for large-wall-thickness acid-resistant pipeline steel X70MS with good low-temperature drop weight performance. The hot rolling process method is characterized in that the pipeline steel comprises the following chemical components in percentage by mass: 0.03%-0.04% of C, 0.2%-0.4% of Si, 1.0%-1.2% of Mn, 0.3%-0.5% of Cr, 0.3%-0.4% of Cu, 0.3%-0.5% of Ni, 0.10%-0.25% of Mo, 0.03%-0.04% of Nb, 0.01%-0.015% of Ti, 0.005%-0.008% of Ce, less than or equal to 0.004% of S, less than or equal to 0.008% of P and the balance of Fe and inevitable impurities. A continuous casting billet with the thickness of 360 mm or above is adopted for production, and the thickness of a finished product is 40-55 mm; a three-stage rolling process and a matched intermediate billet cooling and after-rolling ultra-fast cooling process are adopted, and the produced pipeline steel has good low-temperature plastic deformation performance and good hydrogen induced cracking resistance.

The invention discloses a non-homogeneous high-strength crack arrest resistant structural steel plate and a manufacturing method thereof. A high-performance steel plate with a bainite structure is obtained by adopting a specific chemical composition design and a steel plate modulation process. The purity of the steel is further improved by smelting and continuous casting control technology, internal defects such as segregation and looseness are eliminated, non-metallic inclusions are reduced, and the cast structure is homogenized, so that the steel plate has large thickness, high strength and toughness, non-homogeneity, high mold weldability and excellent crack arrestability, and its yield ratio is 0.69-0.74, and the safety performance is high. Therefore, the structural steel plate of the invention can be used for the production of steel structures such as bridges and high-rise buildings, and effectively solves the problem that conventional steel materials cannot meet the demand for wind power steel due to insufficient strength and crack arrest resistance.

This invention discloses a layered concrete structure with anti-penetration and filtering properties and its preparation method. It solves the problem in existing technologies where only the composition of the concrete layers is changed without improving the overall filtering performance. This invention has the beneficial effects of improving filtering performance and preventing further crack development. The specific solution is as follows: A layered concrete structure with anti-penetration and filtering properties includes a fiber-reinforced concrete layer and an intermediate composite material layer. The intermediate composite material layer is placed between two fiber-reinforced concrete layers. The fiber-reinforced concrete layer and the intermediate composite material layer are periodically arranged to form a layered concrete structure to enhance the filtering performance and improve the anti-penetration performance. The fiber-reinforced concrete layer contains steel fiber reinforcement to enhance the anti-penetration performance of the layered concrete structure. The wave transmittance in the intermediate composite material layer is different from that in the fiber-reinforced concrete layer, and the intermediate composite material layer is bonded to the fiber-reinforced concrete layer.

Provided is a high-strength galvanized steel sheet having a yield strength of 1000 MPa or more and excellent workability, impact resistance, and crack resistance. The amount of diffusible hydrogen in the steel of the steel sheet is 0.60 ppm by mass or less. The steel sheet has a component composition containing, in mass%, 0.150 to 0.450% of C, 0.50 to 3.00% of Si, 1.50 to 4.00% of Mn, 0.100% or less of P, 0.0200% or less of S, 0.100% or less of Al, 0.0100% or less of O, and 0.0100% or less of N, with the remainder being Fe and unavoidable impurities. In the microstructure of the steel sheet, the total area ratio of tempered martensite and bainite is 55-95%, the area ratio of retained austenite is 5-30%, and the abundance ratio (X / Y) of a structure X having a nanohardness of 7.0 GPa or more and a structure Y having a nanohardness of 6.5 GPa or less is 0.5-2.5.

The present invention discloses a high-toughness, high-crack arrest steel for hydrogen pipelines and a preparation method thereof, and belongs to the technical field of pipeline steel preparation. The high-toughness, high-crack arrest steel for hydrogen pipelines includes the following components by mass percentage: C: 0.04-0.07%; Si: 0.30-0.45%; Mn: 0.7-1.0%; Mo: 0.15-0.25%; V: 0.05-0.08%; Nb: 0.02-0.06%; P≤0.012%; S≤0.005%; the balance is Fe. The present invention realizes gradient temperature rolling through controlled rolling and controlled cooling to obtain a gradient flattened ferrite structure, which is beneficial to changing the crack propagation path under the action of low-temperature impact loads, delaying the crack propagation process, and improving the low-temperature toughness and crack arrest performance of hydrogen pipeline steel. In addition, the present invention uses the synergistic effect of cyclic phase transformation and Nb and V micro-alloying to refine the microstructure during the gradient temperature rolling process, further improving its strength and toughness.

Provided is a high-strength steel sheet which has a yield strength of 800 MPa or more and which has excellent workability, impact resistance and crack resistance. The amount of diffusible hydrogen in the steel is 0.50 ppm by mass or less. The steel sheet has a component composition containing, in mass%, 0.150 to 0.500% of C, 0.01 to 3.00% of Si, 1.50 to 4.00% of Mn, 0.100% or less of P, 0.0200% or less of S, 0.100% or less of Al, 0.0100% or less of N, and 0.0100% or less of O, with the balance being Fe and unavoidable impurities. The total area ratio of tempered martensite and bainite is 55-95%, the abundance ratio (A / B) of a structure A having a nanohardness of 7 GPa or more and a structure B having a nanohardness of 6 GPa or less is 0.8-2.5, and the solid solution carbon concentration in the retained austenite is 0.50-0.90 mass%.

The invention discloses a high fracture toughness flux-cored wire for ocean engineering, which comprises a carbon steel sheath and powder filled in the sheath, and is characterized in that the powder comprises non-metal powder and metal powder; the non-metal powder comprises the following components in parts by weight: 360-380 parts of titanium dioxide; 13 to 25 parts of quartz; 40 to 50 parts of potassium silicotitanate; 35 to 55 parts of sodium silicotitanate; and 13-18 parts of cryolite. The welding wire is suitable for multi-layer and multi-pass welding of an EH36 steel plate with the thickness of 80 mm; and the welding heat input is controlled to be 12-25 kJ / cm, and good process adaptability is achieved.

The invention discloses a production method of a high-crack-arrest ultra-thick and ultra-high-strength ship plate, and belongs to the field of steel material preparation. The steel comprises the following chemical components in percentage by weight: 0.05%-0.08% of C, less than or equal to 0.50% of Si, 0.80%-1.15% of Mn, less than or equal to 0.010% of P, less than or equal to 0.002% of S, 0.015%-0.05% of Al, 0.01%-0.04% of Nb, 0.05%-0.07% of V, 0.008%-0.02% of Ti, 0.60%-1.20% of Ni, 0.20%-0.50% of Mo, 0.50%-1.00% of Cr, less than or equal to 0.20% of Cu and the balance of Fe and inevitable impurities. The method breaks through the limitation of the compression ratio of the ultra-thick crack-arrest steel rolled by the continuous casting billet, the online DQ + LT process is adopted for soft and hard phase structure regulation and control, the ultra-thick crack-arrest steel plate with the maximum thickness capable of reaching 100 mm is produced by the continuous casting billet, the ultra-high strength, high toughness and high crack-arrest performance are integrated, the process is simple, the production cost is low, and the method is suitable for large-scale production. And an effective solution is provided for producing the high-crack-arrest ultra-thick and ultra-high-strength ship plate.