31 results about "Yield pressure" patented technology

The invention discloses a high-pressure bursting test system for pressure vessels. The high-pressure bursting test system comprises a high-pressure bursting sample vessel, a high-pressure power source module, a vessel installing and sealing protection device module, a pressure relief device module, and a pressure / flow signal measuring and displaying module, wherein the high-pressure power source module is hermetically connected with the high-pressure bursting sample vessel by the vessel installing and sealing protection device module, the pressure / flow signal measuring and displaying module is arranged on an airflow path / liquid flow path of the high-pressure power source module, and the pressure relief device module is connected between the high-pressure power source module and the high-pressure bursting sample vessel. By using the high-pressure bursting test system for pressure vessels disclosed by the invention, a pressure-liquid feed amount change curve can be measured and recorded in real time, and through analysis on the curve, the volume expansibility, yield pressure, ultimate load, bursting pressure and safety margin of the vessel can be obtained; and the high-pressure bursting test system is high in measurement accuracy and comprehensive in data and can provide more useful information for scientific researches.

The present invention relates to a safe autofrettaged pressure vessel for improving the safety and bearing capability of the vessel and overcoming the technical problem such as unsafety which maybe caused by complex or imprecise calculation of the design of the prior art. The essential points of the technical scheme of the safe autofrettaged pressure vessel are as follows: the depth of a plastic area is calculated according to a formula: k<2>lnk2<j> - k<2> - k2<j> + 2=0, in order to ensure that reverse yield cannot be generated; the bearing capability is calculated according to the graphic formula: P / sigma y =(k<2>-1) / k<2> or P / sigma y =2*(k<2>-1) / (3<1 / 2>*k<2>), in order to ensure Sigma ej <= Sigma y and Sigma ei <= Sigma y, wherein, k is a ratio between external and internal radiuses of the safe autofrettaged pressure vessel; k<j> is a radio between the radius of an elastic-plastic interface and the internal radius; sigma y is a yield strength of the material; p is an internal pressure borne by the vessel; pe is the maximum elastic bearing capability of a non-autofrettaged vessel; Sigma ej is an equivalent stress of a total stress at the elastic-plastic interface; Sigma ei is the equivalent stress of the total stress at the inner wall surface. When k is less than a value determined by a formula of (k<2> / (k<2>-1))*lnk=1, no matter how large the k<j> is, the container cannot generate reverse yield after autofrettaged pressure is released, and at the moment, the maximum bearing capability of the autofrettaged vessel can reach the full yield pressure, namely the formula of p / sigma y =lnk or p / sigma y =(2 / (3<1 / 2>))*lnk.

The invention discloses a PPR / EVOH / POE (Pentatricopeptide Repeats / Ethylene-Vinyl Alcohol / Polyolefin Elastomer) blending high-impact barrier pipe and a manufacturing method thereof, belonging to the field of novel polymeric composite materials. A blending system is formed through physical blending by compositely using PPR, EVOH and POE and compatibilization is carried out on the blending system byadopting a PP-g-MAH (Polypropylene-grafting-Maleic Anhydride) nucleating agent, thus the problems of low temperature brittleness, oxygen and permeability resistance, corrosion resistance, ageing resistance, heat resistance, processability, and the like of a PPR pipe are effectively solved. The PPR / EVOH / POE blending high-impact barrier pipe has the following performances that: drawing yield pressure is 48 MPa, the impact strength of a freely supported beam is 3.6 KJ / m<2>, and oil absorption rate is 0.5%, longitudinal retraction rate is 1%; seepage and crack do not exist in hydrostatic tests and heat stability tests in hydrostatic states; and the PPR / EVOH / POE blending high-impact barrier pipe meets the safety evaluation criterion of domestic drinking water delivery and distribution equipment and protective materials. The invention can be widely applied to the fields of municipal and building water supply, heating, gas supply, electric power, communication, industry, agriculture, and thelike.

The invention provides a high oil peanut quality breeding method which comprises, combining parental generation combination by selecting seeds with good comprehensiveness and high oil content, selecting fine strains at early stage generation, which is high yield pressure screen selecting, determining oil content in each seed of the single strain, screening seeds with high oil content for cultivation on next generation, which is high oil pressure screening, finally selecting fine single strain and determining oil content for each seed of the fine single strain for different separated generations, and accomplishing high yield and high oil pressure selection and oriental cultivation.

The invention provides a breeding method for high-oleic acid high-yield peanut, which includes steps: (1) coordinate parent combination: selecting high-yield germplasm with good integrated character and germplasm with high oleic acid content SPI098 to combine patent; (2) high oleic acid pressure screening: determining oleic acid of each seed in excellent single plant in early separation generation, and selecting excellent peanut seed with high oleic acid content; (3) high-yield pressure screening: planting the screened peanut seed with high oleic acid content in next generation, separating generation in anaphase, and selecting excellent high-yield single plant; and (4) high-oleic acid high-yield peanut variety or strain obtaining: obtaining novel high-oleic acid high-yield peanut variety or strain through multi-generation high-oleic acid high-yield pressure screening. The breeding method provided by the present invention directly screens according to character of oleic acid content inpeanut seed, and has advantages of short breeding period, small blindness, high efficiency, and good economic benefit and social benefit.

The invention relates to a construction method of a walling and filling combined gob-side entry retaining wall body. The construction method comprises the following steps of: closely following forward propulsion of a stope face, erecting dense single supports at a gob retaining side at the rear part of a fully mechanized mining bracket, so that a space of a tunnel at the rear part of the stope face is retained; walling a square template wall with concrete pier blocks under the mask of the dense single props; meanwhile, installing counter-pulled anchor rods which penetrate through the template wall bodies, and carrying out lateral reinforcing on the template wall bodies; carrying out grouting filling on a hollow part defined by the template walls through injected holes reserved on the template walls till the internal spaces of the template walls are filled with grout; carrying out uniform whitewashing treatment on the wall at one side of a gob retaining tunnel to form a concrete spray layer; and sequentially circulating the steps along with propulsion of the stope face till construction of the whole gob-side entry retaining wall body is finished. According to the construction method disclosed by the invention, a brickwork wall and a filling support are combined together, so that the construction method is simple and convenient and simple to operate and ensures that the wall body has high strength and can yield pressure suitably; and length of each walling of the wall body is consistent with the everyday propulsion degree of the stope face, and the construction method is flexibly suitable for actual mining.

A threaded joint which economically imparts effective sealing properties to a metal-to-metal seal portion and which can prevent seizing at the time of make-up comprises a steel pipe 1 having at its tip a male thread 1 b and an unthreaded sealing surface 1 a, and a coupling 2 having on its inner surface a female thread 2 b and an unthreaded sealing surface 2 a. With the yield pressure of the inner surface of the pipe being Py, (1) the average pressure Pm of the annular contact portion satisfies Pm / Py>=3, and the width in the axial direction of the portion which receives a pressure Ps which satisfies Ps / Py>=1 in the annular contact portion is at least 1 mm (or at least 2 mm), and the surface roughness Ry of both unthreaded sealing surfaces is at most 25 mum (or at most 30 mum), or (2) the relationship between the average pressure Pm of the annular contact portion and the surface roughness Ry (mum) of the unthreaded sealing surface satisfies Pm / Py>=0.0032xRy2+1.0, and the width in the axial direction of the portion which receives a pressure Ps which satisfies Ps / Py>=1 in the annular contact portion is at least 1 mm.

The invention provides a circumferentially compressible composite well wall and a construction method thereof which are most applicable to improving the bearing capability of a vertical well wall. The composite well wall comprises a waterproof outer well wall and a circumferentially compressible inner well wall; and the inner wall is provided with at least one compressible insulating layer. In the construction method, firstly, the waterproof outer well wall is built from top to bottom according to the section height; then the inner wall embedded with the compressible insulating layer is builtfrom bottom to top; and finally the wall is built to the designed height according to the section height. When water and soil pressure effects surrounding the composite well wall, the compressible insulating layer of the inner well wall is compressed for yielding pressure so as to enable the stress to be distributed more evenly along the radial direction of the well wall, thus effectively improving the bearing capability of the well wall, effectively reducing the thickness of the existing well wall, improving the utilization ratio of the shaft section, and reducing the engineering cost to a large extent.

The invention provides an equal-strength self-enhancement pressure vessel with the variable structure size, and aims to improve safety of the pressure vessel, reduce manufacturing cost and solve the technical problems that in the prior art, calculation is complicated and inaccurate, and a vessel is unequal in strength, fixed and unreasonable in structure, and inflexible in design. The equal-strength self-enhancement pressure vessel has the advantages that under the condition that loads are unchanged, the structure size is flexible and changeable, and the equal-strength structure is achieved (the total stress in a plastic zone is constant and the total stress of an elastic zone is constantly smaller than yield strength). According to the technical scheme, when the diameter ratio k is larger than the kc lambada value which is determined by a formula, the superstrain degree epsilon lambada of the vessel is determined according to another formula: k21n (epsilon lambada (k-1) +1) 2-(lambada -1) k2-(epsilon lambada (k-1) +1) 2 +lambada=0, and the internal pressure p of the vessel is lambada times of the initial yield load pe of a vessel with the same size and free of self-enhancement; when k is smaller than or equal to the kc lambada value which is determined by the formula, the superstrain degree of the vessel can be 100%, and in the self-enhancement pressure vessel of which maximum bearing capacity can be total yield pressure or of the structure, all the stress of the vessel is within a safety range. The diameter ratio k is the ratio of the external radius of the vessel to the internal diameter of the vessel.

The invention relates to a reinforced yielding U-shaped steel bracket which comprises first support section steel vertically arranged on two sides of a roadway, wherein second support section steel for supporting surrounding rocks at the cambered top of the roadway is arranged at the upper ends of the first support section steel, and is bent into a curved structure; two ends of the second support section steel are movably matched with the upper ends of the first support section steel in the vertical direction respectively; slip limiting yielding mechanisms for stopping the second support section steel moving downwards are arranged at the overlapping parts of the first and second support section steel. Such yielding U-shaped steel brackets can be arranged at intervals in the length direction of the roadway, and the pressure of the surrounding rocks at the top of the roadway is released and transmitted to the second support section steel, so that a sufficient yielding amount is provided for the surrounding rocks at the top of the roadway to avoid the condition that the U-shaped steel brackets reach the yield strength to cause buckling, kicking and collapsing of the U-shaped steel brackets, and further ensure effective support to the surrounding rocks at the cambered top of the roadway, and yielding pressure release and rigid support of the surrounding rocks at the cambered top of the roadway are realized.

The invention discloses a pressure-yielding anchor device, which comprises an extrusion head, a pressure-yielding sleeve and anchor bars, wherein the extrusion head is a cylinder with the conical surface at the lower part and movably connected with the anchor bars into a whole; and the extrusion head is arranged in the pressure-yielding sleeve, the raised surface matched with the conical surface at the lower part of the extrusion head is arranged on the inner wall of the pressure-yielding sleeve, the pressure-yielding sleeve is a steel pipe with a raised edge on the inner wall preferably, and the raised surface matched with the conical surface of the extrusion head is arranged at the end part of the raised edge. By adopting the pressure-yielding anchor device, the purposes of yielding pressure, dissipating energy and controlling deformation can be realized during anchoring, and the pressure-yielding anchor device is applicable to the anchor bars made of any material. The pressure-yielding anchor device is convenient to manufacture, reliable in effects and applicable to different engineering needs.

Provided is a method that is for designing a corrugated steel sheet and that is characterized by, when designing the corrugated shape of a corrugated steel sheet that configures a corrugated steel sheet pipe of tube diameter D comprising a corrugated steel sheet having corrugations having a wave depth of H, setting the wave depth (H) with respect to the tube diameter (D) in a manner so that, with the presumption that the corrugated steel sheet pipe will incur uniform external pressure at the outer surface, the annular buckling pressure (pcr) when the corrugated steel sheet pipe buckles and the yielding pressure (py) when the corrugated steel sheet pipe yields are equivalent.