52results about How to "Improve residual strength" patented technology

A method for the friction stir welding of two components, in particular of two shell components of a fuselage structure of an aircraft and spacecraft, said method comprising the following method steps: positioning the two components relative to one another in such a way that a connection region is formed between the two components; friction stir welding the two components by means of a friction stir welding tool which penetrates the connection region in order to produce a weld which permeates the connection region with the formation of an unpenetrated weld edge portion of the connection region; and introducing internal compressive stresses, at least in the weld edge portion of the connection region. Further a device for the friction stir welding of two components, in particular of two shell components of a fuselage structure of an aircraft and spacecraft is provided.

The invention discloses a support structure and support parameter design method for a short-distance coal roadway under a goaf in a coal mine. Firstly, the damage depth and yield ratio of the bottom plate caused in the mining process of the upper coal seam are calculated; and then the top plate of the short-distance coal seam is classified; according to The support method is selected according to the classification of the roof; finally, the high-pretension high-strength anchor rod and the anchor cable steel beam structure are designed. The invention adopts high pre-tightening force and high-strength bolt support, which can effectively prevent the roof rock layer from loosening and caving, and can reduce the stress of the upper coal seam that has been affected by the mining of the upper coal seam and whose integrity has been damaged to a certain extent or the collapse of the coal seam after mining. The rock formation in the area is reinforced into a complete composite beam, and then through the suspension effect of the anchor cable channel steel beam, the roof structure changes less during the mining process of the lower coal seam, avoiding large mine pressure, and ensuring the integrity of the lower coal seam roadway.

The invention discloses a warship board multilayer anti-detonation protection structure. The warship board multilayer anti-detonation protection structure comprises a double-layer shell, a void compartment, a first liquid compartment and a second liquid compartment, wherein the double-layer shell, the void compartment, the first liquid compartment and the second liquid compartment are sequentially ranked from the outer side of a warship body to the inner side of the warship body, the water filling height h of the first liquid compartment and the water filling height h of the second liquid compartment are 70%-80% of a compartment height H, the void compartment is separated from the first liquid compartment through a first compartment separation plate, the first liquid compartment is separated from the second liquid compartment through a second compartment separation plate, the second liquid compartment is separated from an inner compartment of a warship through a third compartment separation plate, and the side, towards a compartment body, of the second liquid compartment is fixedly connected with a plurality of longitudinal box girders which are vertically ranked at intervals. The warship board multilayer anti-detonation protection structure with the structural style has the advantages of being light in weight, good in anti-detonation performance, high in residual intensity and the like, when a warship board is impacted by detonation, most detonation impact energy can be absorbed, the compartments of the warship are prevented from being damaged, and personal losses are avoided.

The invention discloses a protection device for the underwater anti contact explosion of a concrete gravity dam heel. The protection device comprises a front panel arranged in sequence from the front to the back, a wave panel, a middle panel, a support partition board and a back panel; the peripheries of the front panel, the middle panel and the back panel are sealed and fixedly connected through a side panel, the wave panel and the front panel and the middle panel are not fixedly connected, the support partition board is used for partitioning the middle panel and the back panel, the support partition board is formed by multiple vertical plates connected together with multiple horizontal plates, and the vertical plates and the horizontal plates partitions the place between the middle panel and the back panel into multiple small cavities which can store sealed air. The deformation and breakage of the front panel and the wave panel are utilized by the protection device to absorb part of the energy from the explosion, then the wave resistance and mismatch resistance principle of the air and the surrounding water medium is utilized, the explosion shock waves are further reflected and attenuated, thus the anti-explosion protection of the gravity dam is increased; the protection device has the advantages of being good in anti-explosion ability, high in residual intensity, simple in structure, and rapid and destruction-free in protection deploying.