IN-TUBE INSPECTION SHELL-DEFECTOSCOPE WITH CONTROLLED MOVEMENT SPEED Russian patent published in 2009 - IPC F16D55/26 F17D5/00 

FIELD: construction industry.

SUBSTANCE: invention refers to in-tube shells. Into in-tube inspection shell-defectoscope with controlled movement speed there introduced is tight container, hydraulic drive. In the back part of cylindrical housing there installed relative thereto is the module movable in axial direction, which contains poppet shutoff valves entering passage openings of cylindrical housing. At that, movable module consists of front and rear steel walls with holes, and those walls are connected to each other with hollow cylinder with thickenings, in which rods with poppet shutoff valves are installed in the front part of movable module; on external surface of hollow cylinder there installed is polyurethane hollow cylinder with four external longitudinal slides entering four steel slots of cylindrical housing; at that, tight container is coaxially connected to the end surface of cylindrical housing; inside it there installed is electric motor of hydraulic pump, electric drive of fluid distributor, a fluid tank and control system; in central part of the tight container there installed is hydraulic motor the stock of which is connected with an elastic connection joint to the back cover of the shell movable module; at that, on the stock there installed is displacement sensor the output whereof is connected to negative input of voltage adder of the control system, and its positive input is connected to the programming unit generating the value of the specified stock position owing to voltage so that the control system operating algorithm has the following ratio: where F_y(S) - Laplace representation of control force produced with hydraulic motor; K_F - transfer ratio of in-series connected elements of control system; T - time constant of the forcing link; K_f - transfer ratio of negative feedback from position sensor on the hydraulic motor stock to negative input of the adder as to voltage; U₃(S) - representation of programme voltage specifying as to positive adder input the specified position of hydraulic motor stock; y(S) - Laplace representation of current position of hydraulic motor stock; S - Laplace transformation operator, at that, to hydraulic motor input there supplied from fluid distributor is pressure difference P_H, which is determined by the following formula: owing to which there provided is the possibility for hydraulic motor piston to create pressure force for overcoming friction force and gas pressure force on movable module and for its being moved by value Δy, by which closing of four passage openings with shutoff valves is changed in relation to the specified value, owing to which there provided is control of gas pressure force F_c on the shell: F_c = 2pS_nW², w = υ-V, where V - shell speed relative to the tube; W - gas velocity relative to the shell; U - gas velocity relative to the tube, at that, surface area of opening one passage opening is determined by the following formula:

where R₀ - radius of each passage opening; L₀ - length of poppet shutoff valve; K_l - transfer ratio of hydraulic motor as to the pressure, and value of the specified voltage U₃ is determined and preset with the control system as per the established empirical relation V=V(S) of the shell movement speed V from total surface area S=4S, opening of holes with four passages.

EFFECT: investigating main pipelines with increased movement speed stability.

9 dwg