62results about How to "Reduce extrusion stress" patented technology

The invention provides a self-locking locking mechanism. The mechanism comprises a cylinder body, a front cover, a rear cover, a cone, a supporting ring and a piston, wherein the cylinder body is internally provided with a step; the cone and the supporting ring are arranged between the front end cover and the step in a pressing manner; the piston does reciprocating motion along a hydraulic containing cavity formed by the rear end cover and the step; a plurality of tapered slide ways are distributed on the periphery of the cone; a split clamping block is arranged on the tapered slide ways; the end part of the piston is movably connected with the split clamping block; and the front end cover is provided with a central hole communicated with the cone. The self-locking locking mechanism has the advantages that the locking effect is improved, and the service life and the valid period are prolonged. Continuous high-pressure oil does not need to be introduced into the locking mechanism, so that the energy consumption is reduced; and the split clamping block retracts to clamp a piston rod to realize self locking, and thus the self-locking locking mechanism is safe and reliable. After a die assembly and pressure keeping process is finished, pressure of a lock die cylinder is released, the clamping block is opened, and the piston rod withdraws from the locking mechanism so as to realize automatic unlocking, therefore, a sequence of unlocking and die opening is guaranteed after the pressure is released, and the self-locking locking mechanism is safe and reliable, is easy to operate and eliminates an oil chamber and a relative structure of the conventional locking mechanism. The self-locking locking mechanism has the advantages of small occupied space, simple structure, convenience for machining, small template width and high rigidity.

The invention relates to the field of gas turbine rotors and discloses a wheel disc spigot locating structure of the gas turbine rotor and the gas turbine rotor. Two wheel discs are axially overlapped, axial bumps are arranged at the opposite head faces of the two wheel discs, axial grooves are formed in the other head faces, and the outer diameters of the axial bumps are in interference fit with the inner diameters of the axial grooves; each axial bump is provided with an interference amount adjusting nick; the interference amount adjusting nick is a circular ring-shaped nick formed in the axial head face of the axial bump. By means of the wheel disc spigot locating structure, the wheel disc of the rotor can use a small interference magnitude when assembling, the device extrusion stress is reduced, the assembly is facilitated, the requirement on fixture is lowered, the rotor fits tightly under a working state, and the gas turbine rotor integrity is guaranteed.

The invention relates to a screw bolt fixing mode wheel house installing structure, which comprises a wheel house body, fixing screw bolts, a wheel house cover plate and a transition support frame, wherein at least three installing holes are formed in the center position of the wheel house body, a wheel house cover is fixedly arranged in the center part of the wheel house body, the transition support frame comprises a support frame body and three convex outer edges outwards extending from the support frame body, a screw bolt hole is formed in each outer edge, at least three installing holes are formed in the support frame body, the installing holes formed in the support frame body are matched with the installing holes of the wheel house body and are fixed through the fixing screw bolts, and the screw bolt holes formed in the convex outer edges of the support frame body are fixed to wheel screw bolts.

The invention provides a graphite piece, its processing method, and single crystal growth equipment. The treatment method comprises steps: 1) cleaning and drying the graphite piece; 2) attaching graphite paper matching the shape of the graphite piece on the surface of the dried stone grinding piece, and then curing; 3) coating the organic tantalum solution on the surface of the graphite paper , the coating amount of tantalum is 0.001g / mm 2 -10g / mm 2 , and then sequentially dried and sintered at a high temperature to obtain a cracked tantalum carbide layer on the surface of the graphite paper; the pressure of the high-temperature sintering is below 0.01mbar, the temperature is 1700°C-2500°C, and the high-temperature sintering time is 6h-15h; 4) the The graphite piece formed with the tantalum carbide layer is cooled and put into the silicon-containing material, and the graphite piece is baked for a predetermined time under a preset pressure and a preset temperature. Compared with the prior art, the present invention can ensure that the surface of the prepared graphite parts is not corroded when applied in a thermal field environment, and the prepared graphite parts have considerable strength, which can provide a certain structural support.

The invention discloses a wave plate falling device of a welded metal corrugated pipe, which is mainly characterized in that a lower die assembly comprises a lower die base, a cutting die, an external pressure plate and an internal pressure plate. The upper end of the cutting die protrudes out of the top face of the lower die based and the top face of the cutting die is in a wave plate curve face. The external pressure plate is attached to the outer wall of the cutting die. The top face of the external pressure plate is aligned with the side face outside the cutting die and forms a first chamfered angle with the top end of the external pressure plate at the attached place of the cutting die. The internal pressure plate is placed in the cutting die, and the bottom face thereof leans against the lower die base through an elastic mandrill. The internal pressure plate is attached to the inner wall of the cutting die, and the to top face of the internal pressure plate is aligned with the highest point on the top face of the cutting die and forms a second chamfered angle with the top end of the internal pressure plate at the attached place of the cutting die. An upper die assembly comprises a rubber template fixed on the bottom face of the upper die base. The bottom face of the rubber template is planar. The rubber template flexibly squeezes, molds and cuts the wave plate, and the squeezing stress of the wave plate is small, so that the wave plate does not deform in case of stress recovery, and the molded wave plate is accurate in parameters and burr-free.

The three-layer core-wrapped silicon carbide fiber wire of the present invention includes a SiC fiber core wire, the outer side of the SiC fiber core wire is a polytetrafluoroethylene intermediate layer, and the outermost layer is an aramid outer wrapping layer, which is suitable for a two-dimensional SiC fiber preform stitching to prepare two-dimensional SiC / SiC composites. The invention uses the characteristics of aramid yarn wear resistance and other characteristics as the outer wrapping layer, wraps the SiC fiber core wire with the polytetrafluoroethylene intermediate layer, and prepares the three-layer core-wrapped wire whose outer layer is closed and round and the core wire is not easily broken, thereby ensuring When the SiC fiber is used as a suture, it does not directly contact with the SiC fiber cloth when it penetrates into and out of the laminated SiC fiber cloth, which reduces the frictional force and extrusion stress on the SiC fiber suture and ensures the integrity of the SiC fiber suture after stitching. It has good stability and continuity, and solves the problem of easy thread breakage when using traditional carbon fiber as suture.