40results about How to "Uniform strain distribution" patented technology

A coiled tubing connector having a body and a plurality of entry or transition sections connected to the body wherein the connector has a low cycle fatigue life of at least 30%, more preferably at least 50% of the coiled tubing. A preferred embodiment contains two shoulders that form an annular void, a plurality of centralizers about an exterior of the body, and / or a plurality of elastomer molds separating the centralizers. The connector is preferably longer than the connectors of the prior art and is a composite of fluoroplastics or aluminum alloys.

Embodiments of the present invention provide a system and a method for increasing the harvested energy from a piezoelectric element exposed to environmental vibrations via a two-prong system. In a first prong, a cantilever beam is tapered and shaped so as to increase and provide an approximately uniform strain on and along the beam, thus resulting in increased voltage. In a second prong of the system and method, a voltage compensating circuit, when used with a voltage inversion circuit of the prior art, increases the harvested power by injecting current to the piezoelectric element after each voltage inversion so as to increase the voltage level.

The invention provides a reciprocating extrusion and heading device for preparing ultrafine crystal cake-shaped materials, which includes an upper punch, a die, a lower punch and a base, the base is detachably arranged at the bottom of the die, and the die The mold is provided with an upper cavity and a lower cavity that communicate with each other, and the inner side of the bottom of the upper cavity is arc-shaped with an extrusion port, the inner side of the lower cavity is also arc-shaped, and the inner side of the upper cavity is curved. The arc has the same radius as the arc on the inside of the lower cavity. The present invention has the following beneficial effects: the constriction area of ​​the die of the present invention adopts a circular arc transition, which effectively avoids the slow and uneven extrusion dead zone in conventional extrusion, uniform strain distribution, and small grain dispersion.

The invention belongs to the field of pressure processing of steel materials, particularly relates to a forging-and-rolling compounded forming method for comprehensively promoting internal and external quality of wide and thick plate blanks. Numerical simulation technique is adopted to study internal strain distribution of the plate blanks formed by pure rolling, pure forging and the forging-and-rolling compounded forming method, and the forging-and-rolling forming method is provided and includes steps of 1), firstly heating the plate blanks to be cast; 2), subjecting the plate blanks to forging and deforming in a large hydraulic press after heating the same; 3), returning the plate blanks to be forged in a heating furnace for heat preservation after forging and deforming; and 4), delivering the forged plate blanks in a heated manner to a rolling mill to be rolled after heat preservation or cooling the same slowly to room temperature prior to being heated and rolled again. The forging-and-rolling compounded forming method has the advantages that the forging-and-rolling compounded forming method is applicable to forming process of various molded wide and thick plate blanks (slab ingot), especially to blanks with central looseness; by the method, the defect of core density loose of the wide and thick plate blanks can be overcome, micro-segregation can be alleviated, and texture of the plate blanks can be refined and distributed well; and meanwhile, surface quality of the steel plates can be guaranteed, working allowance can be reduced, and the finished wide and thick plate blanks with 'internal solidness and external refinement' can be realized.

The invention relates to a variable-channel extrusion die and a forming method. The variable-channel extrusion die comprises a male die (1) and a female die (3), a die cavity of the female die sequentially comprises a feeding section (4), a front forming section (5), a middle forming section (6), a rear forming section (7) and a discharging section (8) from an inlet of a blank (2) to an outlet ofthe blank (2), wherein the feeding section (4) is a circular equant channel, the front forming section (5) is a circular-elliptical transition channel, the middle forming section (6) is a prismatic elliptical channel, the rear forming section (7) is an elliptical-circular transition channel, and the discharging section (8) is a prismatic circular channel; and the blank (2) enters from an inlet ofthe female die (3) and is limited by the die cavity of the female die (3) to change a circular cross-section into an elliptical cross-section and change the elliptical cross-section into the circularcross-section in order to form a performed workpiece. The variable-channel extrusion die has simple structure, low load, low cost and high efficiency and can be widely applied to producing rods and wires of steel and nonferrous metal and forging and blanking difficultly deformed materials of large-scale shaft parts, high-speed steel, powder metallurgy, and the like.

The invention discloses a method for making a molybdenum alloy boat, which includes the following steps: (1) preparing a molybdenum slab: a. Ingredients: the molybdenum slab is prepared from the following raw materials in weight percentage: Al(NO3)3: 1.0% to 4.0% , La(NO3)3: 0.5-3.0%, TiH2: 0.5-1.2%, polyethylene glycol: 0.4%-0.7%, silicon powder: 0.5-1.5%, and the balance is molybdenum powder and unavoidable impurities; b, Preparation of alloy powder; c. Compacting and sintering: the alloy powder is compacted and sintered to obtain molybdenum slabs; (2) rolling: the molybdenum slabs are processed into blanks, hot rolling, warm rolling, cold rolling and annealing processes Molybdenum alloy; (3) Cutting and bending: Cut out four squares at the four corners of the molybdenum alloy, and bend the four sides respectively; (4) Welding and forming. The molybdenum alloy used in the molybdenum alloy boat has high tensile strength and high elongation, and the manufactured molybdenum alloy boat has high yield and low cost.

The invention discloses a reinforced concrete column with non-adhesive ends and a preparation method thereof. All longitudinal reinforcing bars in plastic hinge regions at both ends of the column are respectively sheathed by a steel strip corrugated pipe of which the length is twice of the height of the column section, and a 914 adhesive is utilized to attach foam gaskets to the two ends of the corrugated pipe, so that the foam gaskets and the bars in the region form a closed integral body; and thus, a non-adhesive section with a certain length is formed between the longitudinal bar at partial ends and the concrete. The bar strain distribution at the non-adhesive section of the column ends can be uniform, and a yield section with synchronous and slow stress increase is formed, thereby postponing and even preventing the buckling fracture and resilience degeneration, effectively enhancing the ductility and energy consumption capacity of the column end plastic hinge regions, and obviously improving the damage of the concrete in the region due to binding force. The whole system has the advantages of simple structure and favorable economical efficiency, and is convenient for construction.

The invention discloses a restrictive mold pressing mold for ultrasonic vibration auxiliary demolding and a grain refinement method, and relates to mold machining and manufacturing and an applicationmethod thereof, in particular to a mold capable of enabling workpieces to obtain large accumulation strains and a process method for refining material grain sizes. The restrictive mold pressing mold comprises a mold frame, an ultrasonic auxiliary demolding device and a mold cavity. The ultrasonic auxiliary demolding device and the mold cavity are mounted in the mold frame together. The novel restrictive mold pressing mold for ultrasonic vibration auxiliary demolding and the grain refinement method have the beneficial effects of being novel in structure, easy and convenient to machine and operate, good in workpiece adaptability, uniform in strain distribution and small in wear, facilitating demolding and the like, and integrating economic performance and practicality.

The invention relates to a follow-up pressure maintaining type flexible stretch forming machine based on vertical loading. The follow-up pressure maintaining type flexible stretch forming machine is used for plastic machining equipment of plate part three-dimensional curved surface forming. According to the aims of the follow-up pressure maintaining type flexible stretch forming machine, control and operation of the flexible stretch forming machine are simplified, the manufacturing cost is reduced, and intelligent self-adaptive precise control in the plate forming process is achieved; and meanwhile, the stress and strain of formed parts are distributed uniformly, the resilience value is reduced, and the quality of the formed parts is improved. The machine is mainly composed of a rack (1), pre-stretching mechanisms (2), follow-up pressure maintaining mechanisms (3), material clamping mechanisms (4) and a vertical loading mechanism (5). The two ends of the rack (1) are connected with the two horizontal pre-stretching mechanisms (2) and a row of the multiple follow-up pressure maintaining mechanisms (3) and material clamping mechanisms (4) correspondingly. The vertical loading mechanism (5) is arranged at the middle position of the rack (1). One end of each pre-stretching mechanism (2) is hinged to the rack (1), and the other end of each pre-stretching mechanism (2) is hinged to a horizontal movement strip (6). One end of each follow-up pressure maintaining mechanism (3) is hinged to the corresponding horizontal movement strip (6), and the other end of each follow-up pressure maintaining mechanism (3) is connected with the corresponding material clamping mechanism (4) through a semispherical pulling rod.

A production method includes producing a rare-earth magnet precursor (S′) by performing first hot working in which, in two side surfaces of a sintered body, which are parallel to a pressing direction and are opposite to each other, one side surface is brought to a constrained state to suppress deformation, and the other side surface is brought to an unconstrained state to permit deformation; and producing a rare-earth magnet by performing second hot working in which, in two side surfaces (S′1, S′2) of the rare-earth magnet precursor (S′), which are parallel to the pressing direction, a side surface (S′2), which is in the unconstrained state in the first hot working, is brought to the constrained state to suppress deformation, and a side surface (S′1), which is in the constrained state in the first hot working, is brought to the unconstrained state to permit deformation.

The present application discloses a thrombectomy bracket and a thrombus catcher, wherein the thrombectomy bracket is a self-expandable tubular grid structure, and the thrombectomy bracket includes a plurality of connected first grid units, and the first grid The unit includes a plurality of side bars, and the cross-sectional area of ​​the side bars gradually increases along the direction from the middle of the side bars to the two ends of the side bars. By setting the side bars of the first mesh unit along the direction from the middle to both ends, the cross-sectional area of ​​the side bars gradually increases, so that the stiffness of the side bars gradually increases along the direction from the middle to both ends, reducing the end of the side bars And the strain amount near the end area makes the stress and strain distribution of the thrombectomy bracket even when deformed, avoids the stress and strain concentration in the local area, and avoids the deformation of the thrombectomy bracket to affect the size, and improves the resilience of the thrombectomy bracket.