69results about How to "Precise control of tension" patented technology

The invention relates to a tensioning device and method of a prefabricated track plate. The tensioning device comprises a side face tensioning mechanism, an end face tensioning mechanism, a power mechanism, a positioning mechanism and a control mechanism, wherein the side face tensioning mechanism is provided with a plurality of side tensioning units and a plurality of side tensioning power units. The side tensioning units are driven by the side tensioning power units independently to be tensioned. The end face tensioning mechanism is provided with a plurality of end tensioning units and a plurality of end tensioning power units. The end tensioning units are driven by the end tensioning power units independently to be tensioned. The power mechanism is connected with the side tensioning power units of the side face tensioning mechanism and the end tensioning power units of the end face tensioning mechanism so as to provide tensioning driving force. The positioning mechanism corresponds to a mold to be tensioned so as to adjust the height of the mold to be tensioned. The control mechanism is connected with the side face tensioning mechanism, the end face tensioning mechanism and the power mechanism. Tensioning is performed through the multiple tensioning units at the end and side mold directions, so that the tensioning efficiency is greatly improved, and the production period of the prefabricated track plate is shortened.

The invention discloses an unloading method of net frame lifting frames. The unloading method of the net frame lifting frames comprises the following steps: installing support bases at the tops of net frame supports; installing a plurality of lifting frames at the tops of the net frame supports at intervals; lifting net frame structures to the height of the support bases through jacks at the tops of the lifting frames; connecting the net frame structures with the support bases at the tops of the net frame supports with no lifting frame installed through rod members; connecting the support bases at the tops of the net frame supports with the lifting frames installed through the unblocked rod members which are arranged among the net frame structures and prearranged connection paths; partially unloading tension of the jacks according to preset values; arranging through holes on the portions on the walls of the lifting frames and blocking the prearranged connection paths; connecting the net frame structures with the support bases at the tops of the net frame supports with the lifting frames installed through the through holes; removing all tension of the jacks; and removing the lifting frames. The unloading method of the net frame lifting frames can prevent the net frames with no lifting frames installed from deforming and has the advantages of being high in stability and safety.

The invention relates to a method for preparing a pre-tension membrane structure antenna. The method comprises the following steps: designing a membrane surface into a base membrane and electric membranes, splicing the base membrane and forming the electric membranes; marking out a bottom membrane according to a designed paste range, pasting the electric membranes; processing catenaries, splicing auxiliary strengthening plates, positioning the membrane surface by utilizing installation holes of a support framework of the membrane antenna and placing the first membrane surface on a corresponding position of the support framework; reversely loading pretightening force on the long side of the membrane surface by utilizing auxiliary loaded ropes and the support of the support framework, pre-tensioning tension ropes by an adjustment device and adjusting the tension ropes to designed positions for splicing and fixing; and installing a dielectric Kevlar / Nomex honeycomb panel so as to finally realize an antenna array surface. In the method, a phased-array antenna array surface is realized through a membrane structure; the weight of a traditional phased-array antenna structure is lightened; and the method provided by the invention has the characteristics that the pre-tension membrane structure antenna is capable of being continuous loaded; the membrane tension can be accurately controlled, the operation is convenient, a special membrane tying tool is not needed, and the like.

The invention belongs to bridge construction, and particularly relates to dynamic real-time monitoring method for concrete bridge prestressed tendon tensioning force and a special prestress construction system. The dynamic real-time monitoring method for the concrete bridge prestressed tendon tensioning force includes the steps of initializing and real-time dynamic control loading. The prestress construction system comprises at least one tensioning device, and each tensioning device comprises a hydraulic station, a reversing valve bank, a jack, an A / D data collecting module, a PLC, a central processing unit, a human-computer interface, a direct force measuring device, a hydraulic force measuring device, a prestressed tendon elongation measuring device, a friction resistance test device and a security alarm device. The double-control requirement, difficult to met in the prior art, for taking stress control as the principle thing and an elongation value as a checking item is met, the dynamic real-time monitoring method has the advantages that construction quality and safety can be effectively ensured, and problems found in the tensioning process can be solved in time.

This application belongs to the technical field of mechanical processing, and discloses a method for controlling the tension force after welding the induction diaphragm of a capacitive thin film vacuum gauge, comprising the following steps: welding the sensing diaphragm to the cylindrical cavity of the capacitive thin film vacuum gauge The lower end of the body; the yield strength of the material of the cavity is lower than that of the sensing diaphragm; the pressure is unloaded after the pressure is applied on the inner wall of the cavity, so that when the pressure is applied, the inner part of the cavity wall of the cavity and the cavity of the cavity The outer part of the wall and the sensing diaphragm are in the state of plastic deformation, elastic deformation and elastic tension respectively, so that the sensing diaphragm has the required tension after unloading the pressure; the sensing diaphragm of the capacitive thin film vacuum gauge The tension control method after sheet welding is beneficial to realize the precise control of the tension force after induction diaphragm welding.

The invention discloses an unloading method of net frame lifting frames. The unloading method of the net frame lifting frames comprises the following steps: installing support bases at the tops of net frame supports; installing a plurality of lifting frames at the tops of the net frame supports at intervals; lifting net frame structures to the height of the support bases through jacks at the tops of the lifting frames; connecting the net frame structures with the support bases at the tops of the net frame supports with no lifting frame installed through rod members; connecting the support bases at the tops of the net frame supports with the lifting frames installed through the unblocked rod members which are arranged among the net frame structures and prearranged connection paths; partially unloading tension of the jacks according to preset values; arranging through holes on the portions on the walls of the lifting frames and blocking the prearranged connection paths; connecting the net frame structures with the support bases at the tops of the net frame supports with the lifting frames installed through the through holes; removing all tension of the jacks; and removing the lifting frames. The unloading method of the net frame lifting frames can prevent the net frames with no lifting frames installed from deforming and has the advantages of being high in stability and safety.