37results about How to "Economical and reasonable design" patented technology

The present invention relates to the technical field of internal combustion engines, in particular to a method for determining the working compression ratio of a reciprocating internal combustion engine, comprising the following steps: determining the working temperature limit of the gas power cycle; determining the target compression ratio according to the working temperature limit, and using the target compression ratio as the reciprocating The working compression ratio of the type internal combustion engine; wherein, the target compression ratio is the compression ratio corresponding to the gas power cycle when the cycle specific work is the largest or the average effective pressure of the cycle is the largest. The method for determining the working compression ratio of the reciprocating internal combustion engine proposed by the invention solves the problem that the working compression ratio of the existing internal combustion engine needs to be determined only by experience.

The invention discloses H2S corrosion-resistant 80-ksi casing steel for shale gas. The casing steel is prepared from, by weight, 0.25%-0.29% of C, 0.20%-0.35% of Si, 0.90%-1.10% of Mn, 0.95%-1.15% of Cr and the balance Fe, residual elements and unavoidable impurities. The invention further discloses a preparation method of the H2S corrosion-resistant 80-ksi casing steel for the shale gas. The preparation method comprises the steps of steelmaking, wherein pig iron and waste plain carbon steel are adopted as raw materials in the steelmaking process, a deoxidizing agent is added in the steel tapping process, static blowing treatment is performed in a VD vacuum chamber, and argon blowing and sealing gasket adding for protection are performed during pouring; pipe manufacturing, wherein the temperature of a heating zone ranges from 1210 DEG C to 1270 DEG C, and the temperature of a soaking zone ranges from 1240 DEG C to 1260 DEG C; heat treating, wherein the heat treatment technologies of spraying and inner axial flow water cooling quenching, air cooling tempering and straightening under the temperature are adopted. According to the casing steel, the yield strength is 552-655 MPa, the tensile strength is larger than or equal to 655 MPa, the transverse 10*10-mm V-shaped impact energy at 0 DEG C is larger than or equal to 40 J, the elongation is larger than or equal to 19%, and the allowed hardness change delta HRC is smaller than or equal to 3.0.

The invention relates to an electroslag remelting furnace. The invention aims at providing to an electroslag remelting furnace with which three-phase power supply is adopted. With the electroslag remelting furnace, double arm electrodes are replaced in turn, and the double arms work alternately. The electroslag remelting furnace comprises an elevation platform and a platform elevation device used for driving the elevation platform to move up and down. A motorized flatcar is arranged on the elevation platform. A crystallizer is arranged on the top of the motorized flatcar. Two columns are arranged beside the platform elevation device. A cross arm is arranged on the upper part of each column. The cross arms and the columns are connected through connection devices. The connection device comprises a rotation device which can drive the cross arms to rotate around the axes of the columns, and an elevation device which can move along an axial direction of the columns. Fixture heads used for fixing electrodes are arranged at free ends of the cross arms. The electroslag remelting furnace has the advantages that: network load is balanced, and interference is low; electroslag ingot uniformity and compactness are improved; the furnace is suitable for the productions of large-tonnage and large-size metal materials, especially electroslag ingots with 10-150 tons, which are used in high-end large forgings such as nuclear power main pipes, reactor internals, ultra-supercritical rotors, and the like.

The invention discloses an HRB500E seismic steel bar and a preparation method thereof. The steel bar is composed of the following elements in percentage by weight: 0.20-0.25% of C, 0.40-0.65% of Si, 1.20-1.60% of Mn, not greater than 0.045% of P, not greater than 0.045% of S, and 0.050-0.110% of V. The method comprises the following steps: 1) steel-making and refining; 2) continuous casting; and 3) steel rolling. The steel bar disclosed by the invention is reasonable and economical in chemical ingredient design, and ensured to achieve the technical requirements of the national standard GB1499.2 seismic steel bars and assignment book regulations, and achieve the purpose of saving alloys.

The invention relates to a concrete external wall prestress system establishment method which includes the steps: 1) calculating initially applied tension control prestress of a prestress system; 2) respectively calculating prestress loss of circumferential horizontal prestress tendons and vertical prestress tendons; 3) respectively calculating effective prestress of the circumferential horizontal prestress tendons and the vertical prestress tendons; 4) respectively calculating the number of the circumferential horizontal prestress tendons and the number of the vertical prestress tendons to obtain the arrangement range of the prestress tendons of a whole concrete wall body; 5) calculating the reinforcement area of an anchor bed in the prestress system; 6) arranging the prestress tendons in the concrete wall body according to the obtained number of the circumferential horizontal prestress tendons and the obtained number of the vertical prestress tendons, and performing engineering reinforcement for the anchor bed according to the calculated area of anti-explosion spiral bars and plain bars to establish the concrete external wall prestress system. The method can be widely applied to establishing the concrete external wall prestress system for a large LNG (liquefied natural gas) full-capacity storage tank.

The present invention relates to the field of ship structure design, and proposes a method for determining the load-end shrinkage curve of multi-span longitudinals in consideration of lateral loads, including: establishing a beam or floor plate ( Theoretical model of the multi-span instability of the longitudinal bone under the influence of the lateral movement of the beam) and the longitudinal axial force and lateral pressure at the same time; by solving the differential equation, the additional eccentricity of the longitudinal bone caused by the lateral movement of the beam is obtained; Calculation formula of ultimate load for multi-span instability of longitudinal bone considering lateral load; through edge function and plasticity correction, the ultimate load of multi-span instability of longitudinal bone is obtained as load of multi-span instability of longitudinal bone considering lateral load ‑End contraction curve formula; the above-mentioned technical scheme can be used to expand the existing Smith method for hull girder ultimate load calculation, determine the "double bottom effect" of hull girder ultimate load, and improve the accuracy and speed of hull girder ultimate bending moment calculation.

The invention discloses a low-hardness X70M pipeline steel hot-rolled plate coil and a manufacturing method thereof. Wherein the steel contains 0.061%-0.061% of C; 0.080%, si 0.15%- 0.35%, mn 1.41% toMn 1.41% 1.59%, nb0.060%- 0.080% of V, 0.010%-0.030% of V, 0.008%-0.020% of Ti, 0.13%-0.18% of Mo, 0.13%-0.19% of Cr, 0.020%-0.060% of Al, smaller than or equal to 0.018% of P, smaller than or equalto 0.004% of S and smaller than or equal to 0.007% of N; wherein Pcm is smaller than or equal to 0.19%, and the balance Fe and inevitable impurities. Casting blank thickness below 200 mm. And a casting blank is subjected to hot charging at 500-850 DEG C and heated to 1150-1200 DEG C, the finish rolling temperature of rough rolling is 980-1050 DEG C, the finish rolling starting temperature of finish rolling is 910-960 DEG C, the finish rolling temperature is 780-840 DEG C, the cooling speed is 12-30 DEG C / s, and the coiling temperature is 470-530 DEG C. And the hardness value of the producedX70M-grade hot-rolled plate coil is smaller than or equal to 230 HV10.

The invention relates to a circular anti-leakage reinforced concrete pool which comprises a reinforced concrete pool body. The reinforced concrete pool body is defined by a cylindrical pool wall and a foundation base plate and is characterized in that an interlayer base plate is arranged above the foundation base plate and divides the reinforced concrete pool body into a water storage area and a water non-storage area, and a double-base-plate reinforced concrete structure is formed, so that the influence of the temperature change effect on the pool is concentrated to the pool wall between the foundation base plate and the interlayer base plate, and temperature stress of the water storage area is reduced. According to the circular anti-leakage reinforced concrete pool, due to the facts that the interlayer base plate is arranged above the foundation base plate to form the double-base-plate reinforced concrete structure, and the influence of the temperature change effect on the pool is concentrated to the pool wall between the foundation base plate and the interlayer base plate, the problems that in the prior art, the effect of preventing the pool wall from being cracked is poor, the reinforced structure is complex, the using amount is large, and the cost is high are solved.