69results about How to "Reduce stress concentration factor" patented technology

A wind turbine blade has upper and lower shell members with a respective spar cap configured on an internal face of the shell members. A shear web extends between the spar caps along a longitudinal length of the blade. A connection assembly is configured between the transverse ends of the shear web and the spar caps and includes a channel structure configured on the spar cap. The channel structure includes rigid side walls that extend from the spar cap along the longitudinal sides of the shear web. Bond paste is disposed between the channel structure side walls and the longitudinal sides of the shear web.

The invention discloses a tower frame door opening of a wind generating set and a design method of the tower frame door opening; the tower frame door opening consists of two straight line segments and a curve segment according to shape, and the curve segment consists of more than three circular arcs with different diameters. The thickness of a door frame of the tower frame door opening is 1.15 to 1.17 times of the thickness of a tower tube wall preferentially, the length of the door frame along the radial direction of a tower tube is 4.5 to 5.5 times of the thickness of the door frame preferentially, and the length of the door frame at the central height position of the door opening, which extends out of the tower tube wall, is about half of the length of the door frame along the radial direction of the tower tube. The actual design process of the tower frame door opening comprises an overall data design of a door frame section, a door frame section modeling, a stress concentration factor IIW (International Institute of Welding) interpolation calculation and the like. Firstly, obtain an optimized parameter of the shape of the curve segment at the door opening, secondly, based on the optimized parameter, perform a further optimization to a size parameter of the door frame. The tower frame door opening increases the mechanical property index and reduces the impact of the existing door opening on a tower tube structure.

The invention discloses a designing method for realizing the equal load-carrying of a tension-loaded butt joint with a central crack on a welding line, and the application of a K factor, which belong to the field of welding and aim to solve the problem that the load-carrying capacity of the tension-loaded butt joint with the central crack is lower than that of a parent metal. If the parent metal of the tension-loaded joint with the central crack on the welding line also has a crack, the designing method comprises the following steps of: determining equal load-carrying conditions, and the fracture toughness of a weld metal and the parent metal; calculating a stress intensity factor of a parent metal area and the stress intensity factor of a welding line area meeting equal load-carrying; calculating a stress intensity factor formula; and obtaining geometrical parameter values of the welding line. If the parent metal of the tension-loaded joint with the central crack on the welding line is free from defect, the designing method comprises the following steps of: determining the equal load-carrying conditions, and the tensile strength of the parent metal; calculating the stress intensity factor formula; determining a critical stress relational expression, and the fracture toughness of the weld metal; and obtaining the geometrical parameter values of the welding line. The stress intensity factor of the welding line area is applied to the calculation of critical crack size, critical stress and remaining service life of the tension-loaded joint with the central crack. The method and the application are applied to plate butt joints welded on both sides.

The invention relates to a sheet cage (1) used for a rolling bearing. The sheet cage is used for a roller-shaped rolling element, and comprises a certain quantity of connecting pieces (3) axially extending between rings (5), wherein a cage hole (7) used for accommodating a rolling element (19) is formed between each two adjacent connecting pieces (3), and recesses (11) used for rounding corners (9) are introduced into the corners (9) of the cage hole (7) in all radial directions. On this occasion, the rounded recesses (11) inwardly widen in the radial directions through inclined plant portions (13). The invention also relates to a method for making the sheet cage (1). The sheet cage guarantees the strength required by the connecting pieces in the case of increasing the radius of each of the recesses.

The invention discloses an aggregate through hole pattern structure of a ship cabin wall plate. The structure comprises horizontal straight lines positioned on two sides of an opening of a through hole; the end part of the straight line on the left side is connected with a first arc line; the upper end of the first arc line is connected with a second arc line; the upper end of the second arc line is connected with an upper semicircle; the right lower end of the upper semicircle is connected with a third arc; the lower end of the third arc is connected with a fourth arc; the other end of the fourth arc is connected with the straight line on the right side of the opening of the through hole; and the through hole is an asymmetric hole. Aiming at an asymmetric aggregate for a ship, the hole edge stress concentration coefficient is reduced, and the ship fatigue strength is improved; and for frequent generation of cracks at a weld toe root part of a reinforcing material, the new design frequently adopts a reinforcing material removing method, but the rise of hole edge stress can be caused. The hole pattern can reduce stress concentration points when reducing the stress concentration coefficients to meetthe new design requirements so as to reduce fatigue sources; and compared with a novel hole pattern, the hole pattern is easily positioned, and is convenient for machining.

The invention discloses a welding structure for a ship bulkhead plate aggregate hole and a matched supplementary plate. The welding structure for the ship bulkhead plate aggregate hole and the matched supplementary plate comprises a bulkhead plate and the supplementary plate. The aggregate penetration hole is formed in the bulkhead plate, the aggregate penetration hole and the supplementary plate are welded after an aggregate penetrates through the aggregate penetration hole to be assembled, a hole structure comprises a first arc, the first arc is connected with a first elliptic arc, the elliptic arc is connected with a second arc, the upper end of the second arc is connected with an upper semi-waist circle, the lower end of the upper semi-waist circle is connected with a straight line tangent to the upper semi-waist circle, the supplementary plate is provided with a third arc in the shape, the lower end of the third arc is connected with a second elliptic arc, the second elliptic arc is connected with a fourth arc, the other end of the fourth arc is connected with a fifth arc, the fifth arc is connected with a right angle, the other side of the right angle is connected with a sixth arc, and the sixth arc is tangent to the upper side of the supplementary plate. For the T-shaped aggregate for a ship, the operation requirement for improving the fatigue life of the ship is met through decreasing the stress concentration factor on the side of the hole; the stress concentration factor is decreased, so that the fatigue life of the connection of the supplementary plate and the hole parent material is prolonged; and the assembly is simple and the wide application is realized.

A belt for a continuously variable transmission and elements used in the belt. The elements include a stopper portion formed integrally with a neck portion erected upwardly from a saddle face to hold a width end portion of the ring. The elements are juxtaposed annularly in a same orientation and fastened by rings disposed on a saddle face of the element thereby forming a belt for a continuously variable transmission. A recessed portion is formed by depressing the saddle face at a corner between a side face of the neck portion and the saddle face; and an inner face of the recessed portion includes a first inner face extending smoothly into the side face of the neck portion and having a relatively larger curvature radius, and a second inner face extending smoothly into the first inner face and having a relatively smaller curvature radius.

The invention discloses a structure optimization design method of a powder injection molding supercharger turbine. The structure optimization design method is characterized that the fact that turbine stress concentration factor is minimum under the condition that a turbine structure is lightest and the rotation speed is the highest is used, a target function is optimally designed under the premise that the turbine structure satisfies the strength requirement and the service life requirement, the maximum equivalent stress under the highest rotation speed work state of the turbine is used as the constraint condition, and the turbine structure weight reduction feature geometric size is used as the design variable to build the optimal mathematic model of the turbine structure. The method has the advantages that a powder injection molding process is used, and inherent defects such as heat cracks, shrinkage cavities and shrinkage porosities of precision casting are eliminated effectively; the constraint condition during optimization can be reduced, the existing turbine structure form can be changed, turbine structure can be optimized maximally, the sizes of parts of the turbine are determined by the method, turbine weight can be reduced maximally under the premise that the turbine structure strength requirement and the application requirement are satisfied, and turbine light weight is achieved.

A node structure for connecting a member of a lattice frame to one or more other members of the frame comprises a hollow brace having opposed walls that converge outwardly at an acute angle in cross-section toward a central plane to connect at an outer edge. At least one root portion has a central longitudinal axis extending outwardly in the central plane of the brace for alignment with a member of the frame. The root portion has an inner end cut away at opposite sides around the central plane to leave a joining surface that intersects the converging walls of the brace while embracing an outer region of the brace extending inwardly from the outer edge.