CN106363260A

CN106363260A - Mechanical arm for electrolytic machining of corrosion defects in pipe

Info

Publication number: CN106363260A
Application number: CN201611031427.3A
Authority: CN
Inventors: 余建星; 王华昆; 樊志远; 余杨; 刘晓强
Original assignee: Tianjin University
Current assignee: Tianjin University
Priority date: 2016-11-22
Filing date: 2016-11-22
Publication date: 2017-02-01

Abstract

The invention discloses a mechanical arm for electrolytic machining of corrosion defects in a pipe, and the mechanical arm is used for machining the interior of the pipe. The mechanical arm comprises an upper base 14, an upper mechanical arm body 16, a lower mechanical arm body 2, a wrist 5, a mechanical claw 7 and a cathode corrosion mold 9. An upper rotary plate 3 is fixed to the tail end of the lower mechanical arm body 2, a lower rotary plate 4 is fixed to the top end of the wrist 5, and the lower rotary plate 4 and the upper rotary plate 3 are connected and can rotate around the central axis where the lower mechanical arm body 2 is located. An electrolyte channel is formed between the upper surface and the lower surface of the cathode corrosion mold 9, and an electrolyte inlet guide tube 10 communicating with the electrolyte channel is fixed to the upper surface of the cathode corrosion mold 9. The electrolytic machining on the corrosion defects in the pipe is carried out by continuously injecting electrolytes through the electrolyte channel with the cathode corrosion mold 9 as a cathode and a machining pipeline as an anode.

Description

Pipe fitting internal corrosion defect Electrolyzed Processing machinery arm

Technical field

The present invention relates to a kind of laboratory pipeline inside and outside corrosion default Electrolyzed Processing machinery arm, mainly solve minor diameter pipe The problem of the internal processing difficulties of part is it can also be used to external corrosion shape is processed.Can be inside and outside in free small-diameter pipe fitting using this device Surface Machining goes out corrosion default of different shapes, makes Piping specimen containing corrosion default, thus carrying out the pipeline containing corrosion default Buckling test, probes into the impact to pipe fitting bearing capacity for the internal corrosion defect.

Background technology

Corrosion is widely present in metal material, for Prolonged exposure in the steel plant equipment of corrosive atmosphere, oil gas Corrosive pipeline undoubtedly becomes the main factor of structural failure.For submarine pipeline, due to sour gas, be mingled with crude oil consolidates Body is short grained to be washed away, and transport Korrosionsmedium, frequently can lead to pipeline and during service internal corrosion occurs, adds outside The erosion of sea water, inside and outside corrosion becomes the main inducing of pipeline bearing capacity reduction.Due to inside pipe fitting narrow space, processing and fabricating Pipe fitting sample containing internal corrosion is extremely difficult, which prevent the shadow probing into internal corrosion defect to pipelines in deep sea limit flexing bearing capacity Ring the understanding of rule, this problem derives by the difficult problem that actual tests run into, therefore design a set of energy and be directed to narrow elongated of internal diameter Pipe fitting carries out the device of internal corrosion processing, necessary with the impact to pipelines in deep sea bearing capacity for the further exploration internal corrosion.

Although having a lot of electrolytic machine tools at present, it is directed to the device of slender rectangular tube internal corrosion defect processing also very Few, do not retrieve the equipment being specifically designed for the processing of pipe fitting internal corrosion defect.Cn201410627262.0 discloses a kind of tubular workpiece The numerical control electrochemical machining method of inwall closed curve slot and its clamping device, it is possible to achieve the curvilinear shaped slots processing of pipe fitting, but should The defect in face in the presence of device:

1. equipment is complicated, needs by programme-control machining locus；

2. equipment is huge, and load maintainer is complicated, is to carry out inside in pipe fitting to process curved groove, needs additional motor to assist Pipe fitting is mobile and rotates, to process required grooved.

Content of the invention

It is an object of the invention to overcoming the above-mentioned deficiency of prior art, one kind is provided to can be used for laboratory pipe fitting internal corrosion The device of defect processing.This device utilizes Electrolyzed Processing principle, the inside and outside corrosion default processing of achievable pipeline, thus can be to containing The pipelines in deep sea of corrosion default carries out buckling test, and technical scheme is as follows:

A kind of pipe fitting internal corrosion defect Electrolyzed Processing machinery arm, for processing inside pipe fitting, including top base 14, upper machinery Arm 16 and lower mechanical arm 2, wrist 5, gripper 7 and cathodic corrosion mould 9,

Between top base 14 and upper mechanical arm 16, between upper mechanical arm 16 and lower mechanical arm 2, between wrist 5 and gripper 7 All it is connected by rotating shaft, fasten between gripper 7 and cathodic corrosion mould 9 and be connected；

Be fixed with top rotary table 3 in the end of lower mechanical arm 2, be fixed with lower rotary table 4 on the top of wrist 2, lower rotary table 4 with upper Rotating disk 3 is connected and can rotate around the axis that lower mechanical arm 2 is located；

Offer electrolyte channels between the upper and lower surface of cathodic corrosion mould 9, be fixed with and electricity in upper surface The electrolyte inlet conduit 10 that solution matter passage communicates,

With cathodic corrosion mould 9 as negative electrode, process pipeline is anode, constantly injects electrolyte by electrolyte channels and carries out Pipe fitting internal corrosion defect Electrolyzed Processing.

The present invention can be used for the pipe fitting that making in laboratory contains internal corrosion defect, and then probes into internal corrosion defect to pipeline carrying The impact of power, has the advantage that

(1) device simple, principle is simple, low manufacture cost；

(2), using point solution process principle, load maintainer is simple for this device, and dependable performance can change negative electrode rotten as needed The shape of erosion mould, produces different size of corrosion default, corrosion default can one-shot forming；

(3) do not limited by machined material hardness, machining stress will not be produced, can one-shot forming, processing effect Rate is high, and surface quality is good.

Brief description:

Fig. 1 complete layout

In figure label declaration: 1 time mechanical arm rotating shaft；2 times mechanical arms；3 top rotary tables；4 lower rotary tables；5 wrists； 6 gripper rotating shafts；7 grippers；8 negative electrode power lugs；9 cathodic corrosion moulds；10 electrolyte inlet conduit； 11 bottom bases；12 power cathode joints；13 power anode joints；14 top bases；Mechanical arm rotating shaft on 15；16— Upper mechanical arm.

Fig. 2 negative electrode mould details

In figure label declaration: 6 gripper rotating shafts；7 grippers；8 negative electrode power lugs；9 cathodic corrosion moulds； 10 electrolyte inlet conduit.

Fig. 3 negative electrode die cut view

In figure label declaration: 7 grippers；9 cathodic corrosion moulds；10 electrolyte inlet conduit.

Specific embodiment

Below in conjunction with the accompanying drawings, the specific embodiment of the present invention is further described:

The pipe fitting internal corrosion defect Electrolyzed Processing machinery arm of the present invention mainly includes bottom base 11, top base 14, upper machinery Arm 16 and lower mechanical arm 2, wrist 5, gripper 7 and cathodic corrosion mould 9, under passing through between lower mechanical arm 2 and upper mechanical arm 16 Mechanical arm rotating shaft 1 connects；Lower mechanical arm 2 is connected by gripper rotating shaft 6 with gripper 7, and top base 14 and upper mechanical arm 16 lead to Cross mechanical arm rotating shaft 15 to be connected；(figure can be rotated around the axis that lower mechanical arm 2 is located between top rotary table 3 and lower rotary table 4 1), lower mechanical arm 2 and top rotary table 3 are fastenedly connected, and wrist 5 is fastenedly connected with lower rotary table 4, can relatively rotate between rotating disk 3 and 4.

It is fastenedly connected between cathodic corrosion mould 9 and gripper 7, its concrete form can be changed as needed and (such as change Become hemispherical or hexahedron etc.), so that the corrosion default groove (Fig. 1) going out same form to be corroded on anodic attack pipe fitting.

During practical operation, first bottom base 11 is fixed on testing stand, by power cathode joint 12 and corrosion mould 9 Negative electrode power lug 8 is connected, and power anode joint 13 is connected with corrosion workpiece (inner surface of pipeline, Fig. 3), and mechanical arm is extend into Inside pipe fitting, is made cathodic corrosion mould near inner surface of pipe fitting, is then sprayed toward in processing sample by electrolyte inlet conduit 10 Spill electrolyte solution, make to be formed loop (Fig. 3) between cathodic corrosion mould and Anode machining sample.During beginning, the two poles of the earth (corrosion mode Tool 9 is negative electrode, and processing sample (pipeline) is anode) between gap length, the big (arrow in Fig. 3 of the little place in gap electric current density At head exit position and inner surface of pipeline, gap is minimum), it is fast that anode metal removes speed；And gap general goal electric current density is little, go Except speed is slow.With the continuous dissolving of surface of the work metal material, by adjusting mechanical arm 2,5,16 and gripper 7 and up and down Rotating disk 3,4, makes negative electrode mould 9 constantly feed to workpiece, and the electrolysate of dissolving is constantly imported from entry conductor 10 again Electrolyte wash away, surface of the work (inner surface of pipeline) is also just gradually processed to close to tool-electrode (cathodic corrosion mould 9) shape.Can adjust the relative position (Fig. 1) between mechanical arm 2,5,16 as needed.

Claims

1. a kind of pipe fitting internal corrosion defect Electrolyzed Processing machinery arm, for processing inside pipe fitting, including top base (14), upper machinery Arm (16) and lower mechanical arm (2), wrist (5), gripper (7) and cathodic corrosion mould (9), wherein,

Between top base (14) and upper mechanical arm (16), between upper mechanical arm (16) and lower mechanical arm (2), wrist (5) and machinery All it is connected by rotating shaft between pawl (7), fasten between gripper (7) and cathodic corrosion mould (9) and be connected；

It is fixed with top rotary table (3) in the end of lower mechanical arm (2), be fixed with lower rotary table (4), lower rotary table on the top of wrist (2) (4) it is connected with top rotary table (3) and can rotate around the axis that lower mechanical arm (2) are located；

Offer electrolyte channels between the upper and lower surface of cathodic corrosion mould (9), be fixed with upper surface and be electrolysed The electrolyte inlet conduit (10) that matter passage communicates.With cathodic corrosion mould (9) as negative electrode, process pipeline is anode.