33results about How to "Eliminate tensile stress" patented technology

The extrusion apparatus for preparing superfine crystal block material has one structure comprising a die holder, a connecting seat, a conic die case, a conic die core, a wedged extruding rod with reduced extrusion force to avoid cracking of the block, a turning unit, a square vertical channel, a square horizontal channel and a product outlet. The product has high crystal grain fining and smooth surface, and the extrusion apparatus has simple structure, excellent mechanical performance, easy installation and use, and no pollution.

A shoe sole with a footbed (5) is described which forms a flexible foot support. In order to provide advantageous constructive conditions it is proposed that the foot support consists of a flat structure (4) receiving tensile forces which is held in a freely suspended manner in a frame (1) defining the edge contour of the footbed (5).

The invention provides a method for manufacturing a pre-deformation line diamond line saw through powder metallurgy, comprising the following steps: basic line manufacturing: selecting metal wires, stranding at least two metal wires into a line, and deforming the stranded line by a deformer to obtain a pre-deformation base line; powder preparation: weighing metal powder, a binder and diamond by mass percent, and adding the mixture into a blender mixer to evenly mixing; line blank manufacturing: putting the base line and powder into a mould, and taking the pre-deformation base line as a center to prepare a line blank by using a forming technology; and line saw manufacturing: putting the line blank to a sintering furnace for sintering, and cooling with the furnace to obtain the line saw. The manufacturing method provided by the invention has the advantages of simple process, low cost and high production efficiency. The produced line saw has excellent performance, high strength, good flexibility, high hold to diamonds, stable cutting performance, good chip discharging performance and long service life, and is not easy to crack.

The invention belongs to the technical field of machining of medical titanium alloy materials and particularly relates to a preparation method of a titanium alloy bar of a universal resetting screw seat. The chemical ingredients of titanium alloy comprise, by mass percentage, 5.9%-6.4% of Al, 3.9%-4.4% of V, 0.15%-0.22% of Fe, 0.09%-0.13% of O, not larger than 0.05% of C, not larger than 0.005% ofH, not larger than 0.01% of N and the balance Ti. The preparation method comprises the steps that firstly, a round bar blank is obtained through the procedures of smelting, forging, and rolling; thena beta single-phase section homogenization annealing treatment process is adopted to obtain a homogeneous fine-grained acicular martensite structure, an electrifying straightening and hyperbolic straightening combined process is used for straightening, the electrifying straightening temperature is controlled to be less than 780 DEG C, and a balanced residual stress state is obtained; and finally,stress relief annealing and centerless grinding are conducted to obtain the finished bar. The preparation method of the titanium alloy bar of the universal resetting screw seat can produce a medicalTi-6Al-4V alloy bar basically free of stress, the Ti-6Al-4V alloy bar has excellent fatigue life, and a qualified raw material is provided for manufacturing of universal resetting screw seats of orthopedic medical instruments.

The invention provides a method for realizing stress corrosion resistance of a stainless steel welding connector impacted by nanosecond-pulse laser. According to the method, a welding seam is impacted by adopting laser along an S shape, and an outer region of the welding seam is impacted along a direction parallel to the welding seam, so that pull stress of the welding connector is eliminated. By reasonably selecting power density, phase change does not occur and residual pull stress can be eliminated, so that a condition that the stress corrosion resistance performance of the welding connector is reduced is avoided. According to the method provided by the invention, the surface of a workpiece is impacted through the nanosecond-pulse laser, and no obvious mechanical force is used; a machining speed is rapid and automation is easy to realize; a complicated mold surface can be impacted.

A ram type blowout preventer includes variable ram packers for sealing about tubulars of different outside diameters in the bore of the preventer housing or about a single tubular having a variable outside diameter. Each ram packer includes a body of elastomeric material formed about vertical ribs to conform to tubular having variable OD within a certain range.

The invention discloses an oil baffle plate installation welding mode oil bottom case assembly. An oil baffle plate and a press block used for fixing the oil baffle plate are designed on the side surface of an oil bottom case body, a great distance from the top surface of the oil baffle plate to the flange surface of the oil bottom case body exits, the oil baffle plate is clamped by the press block and is not in contact with the wall surface of the oil bottom case body, and is in segmented welding connection with the bottom surface of the oil bottom case body, the oil baffle plate is transversely provided with a buffer reinforcing rib, an oil sucking disc supporter arranged on the oil baffle plate is in an arched door shape, and the oil baffle plate is not in contact with an oil sucking pipe. The oil baffle plate is clamped by the press block, the height of the oil baffle plate is reduced, the oil bottom case body adopts a segmented welding connecting mode, the tensile stress generated after the oil baffle plate and the side surface of the oil bottom case body are welded is fundamentally eliminated, and in addition, the force, caused by engine oil impact, transferred to an oil bottom case bottom surface welding seam is reduced, so that the reliability and the durability of the oil bottom case assembly are improved.

The invention relates to the field of beam bridge construction and discloses a steel beam segment. The steel beam segment comprises a left part and a right part. A gap formed in an opposite-pulling manner is formed between the left part and the right part. The left part and the right part are connected in a welded manner. A continuous combined beam bridge comprises two abutment piers and at least one middle pier located between the two abutment piers. The pier top of the middle pier is provided with the steel beam segment. Multiple combined beam segments are arranged on the two sides of the steel beam segment. A construction method of the continuous combined beam bridge includes the following steps that firstly, the steel beam segment formed by splicing the left part and the right part is provided, the left part and the right part of the steel beam segment are connected through bolts, and the bolts are tensioned; secondly, the combined beam segments are installed on the two sides of the steel beam segment till a steel beam is closed; and thirdly, the bolts on the steel beam segments are loosened gradually, and the left part and the right part of the steel beam segment are welded. By the adoption of the steel beam segment, the continuous combined beam bridge, and the construction method of the continuous combined beam bridge, the working performance of a concrete bridge panel can be greatly improved.

The invention relates to a double-defense-line flexible anchoring structure of a dam body core wall geomembrane and a foundation concrete structure. According to the double-defense-line flexible anchoring structure of the dam body core wall geomembrane and the foundation concrete structure, a geomembrane in a dam body can be fixed to foundation concrete below the geomembrane. According to the technical scheme of the double-defense-line flexible anchoring structure, an anchoring groove is formed in the top face of the foundation concrete, the interior of the anchoring groove is divided into a plastic deformation area located on the upstream side and formed by filling plastic filler and an anchoring mechanism located on the downstream side, and the geomembrane penetrates through the plasticdeformation area to be fixed to the downstream side in the plastic deformation area through the anchoring mechanism. The double-defense-line flexible anchoring structure is suitable for engineering adopting the geomembrane as the middle anti-seepage core wall of the dam body.