FR2528577A1 - TRACTION RESISTANCE TEST DEVICE AND DRAWING DEVICE FOR A BOLT PROJECTING ON A SURFACE - Google Patents

Abstract

TENSILE STRENGTH TESTING AND STRETCHING DEVICE FOR BOLT PROJECTING ON A SURFACE. IT ALLOWS TO CONTROL THE STRENGTH OF THE CONNECTION BETWEEN A COMPONENT AND A BOLT THAT IS PLACED THERE OR ANY OTHER ANCHOR-SHAPED ELEMENT. THE DEVICE CAN ALSO BE USED TO STRETCH THE BOLT. THE DEVICE CAN ALSO BE USED TO STRETCH THE BOLT. IT ESSENTIALLY CONSISTS OF A TAKING HEAD20, 26 THAT CAN BE COUPLED TO THE SPECIMEN 19, A SUPPORT DEVICE 36, 38 THAT CAN BE FITTED ON A SURFACE18 WHICH SPEAKS THE SPECIMEN19 AND A DEVICE48, 50 IN PARTICULAR A HYDRANIC CYLINDER, COULD FORGET IT. DESIRED TENSION BETWEEN THE JACK HEAD20, 26 AND THE SUPPORT DEVICE36, 38.

Description

Test device for tensile strength and drawing

  for a bolt protruding from a surface.

  The present invention relates to a device for testing tensile strength and drawing for a bolt projecting from a surface. In the construction of apparatus, threaded bolts are frequently welded by arc welding or similar methods end-to-end to a surface of an apparatus. Anchors and anchors for

  In many cases, the strength of the

  The control procedures that were common in the past

  are imprecise, inconvenient and time consuming.

  The subject of the present invention is a tensile strength test device which enables rapid, easy and reliable non-destructive testing of the strength of the

  fixing a bolt protruding on a surface.

  This object is achieved according to the invention by means of a control device comprising a traction device

  can be coupled to the bolt, a support device can

  be placed on the surface and a mechanism intended to

  draw a force between the traction device and the

tif of support.

  The device according to the invention makes it possible to control the resistance of the fixing of projecting bolts, for example by

  what is needed, inter alia, to hear all elements of

  truction in the form of bars or pins This device

  In particular, it allows for the control of

  on the component of the threaded bolts fixed by

  hard, without causing them to twist or bend

the result of the measurement.

  The device according to the invention also allows

  to control the tensile strength of

  welded head cities and anchors for concrete; control fastener load resistance by screwing, welding, brazing, gluing and clamping pin-shaped elements; to stretch pin-shaped components in a controlled manner, for example to cold-consolidate soldering and soldering points and to compensate for length tolerances, or to form a flanged collar on metal sheets, etc .;

  to perform directly on the measurement component

  tensile and elongation rests that are generally only performed in the laboratory with resistance testing machines

fixed traction.

  Other features and benefits will emerge

  the following detailed description of examples of

  Non-limiting embodiment of the invention, with reference to the accompanying drawings, of which: FIG. 1 represents a preferred embodiment of the device for testing the tensile strength and drawing according to the invention;

  FIG. 2 represents a second simple embodiment of

  folded device according to the invention.

  The device for testing the tensile strength and stretching shown in Fig. 1 essentially comprises a gripping head 10, a support device 12, an element

  14 and a set of measurement placed above 16.

  The engaging head 10 provides a secure and rigid coupling of the tensile strength testing device with a test specimen, for example to a threaded bolt 19

  welded butt to a surface 18.

  In the embodiment shown in FIG. 1, the gripping head 10 comprises gripping segments 20 internally having grooves 22 into which a

  collar 24 of an anchor pin or assembly bolt 26.

  The engagement segments 20 are pushed outward by springs 28 which are inserted between them and the bolt

  The grip segments 20 have an overlying

  oblique outer face 30 which attack a correlatively oblique inner surface 32 of a sleeve 34 which is placed

  able to be moved axially in a cylindrical casing

  Fig. 36 of the tensile strength test device At the lower end of the housing 36 is a support ring 38 with which the test device bears on the surface 18 on both sides of the specimen or all around. it Between the support ring and the sleeve 34 are springs 40

  which urge the sleeve to a locking position.

  The sleeve 34 comprises bar-shaped plugs 42 that exit through axial slots 44 formed in the

  casement 36 The casing comprises two other catches 46 in form

  bars between the slots 44 and the support ring 38.

  The assembly bolt 26 is inserted into a web

  wise axial piston 48 of a hydraulic cylinder 50, immo

  bilized by a solid nut screwed 51 and is asked to

  its position extended by a compression spring 52.

  The measuring assembly 16 that can be screwed onto the

  upper end of the hydraulic cylinder 50 includes a dial displacement indicator, which includes a probe

  in the form of a bar 56 which passes through a bore of the

  appearance 26 to enter the interval between

  The indicator 54 is protected by a cy-

  hollow liner 58 made of transparent plastic which is

  placed or screwed on the measuring unit 16.

  The engagement segments have spike-like ends 20a through which they can be coupled

  directly to the specimen, if it contains a cor-

  respondent or, as has been shown, through

  an assembly nut 59 screwed onto the specimen.

  The hydraulic cylinder 50 may be a hydraulic cylinder with a hollow piston that can be supplied with a pressure of 500 bar and is capable of providing a force of 500 bar.

  maximum tension of approximately 70 k N The return spring incor-

  role of poré 52 is to allow the use of all

  the maximum stroke, 12 mm here, at each test.

  Instead of the hydraulic cylinder, one can also use

  use another device to generate the traction force

  necessary, for example a pneumatic cylinder or

  mechanical devices comprising pins, scissors-type joints, knee pads, etc. Instead of or in addition to the indicator, an inductive displacement sensor can be used and can be connected to the fluid circuit under

  pressure for the hydraulic cylinder a pressure sensor

  to measure the tensile and elongation values electronically and process them later, for

  purposes of displaying a stress-strain diagram.

  The description of the handling of the device according to

  FIG. 1, which is concerned with control and stretching,

a threaded lulon q 19.

  The hydraulic control pressure calculated by the quotient of the test pulling force by the active piston surface is measured on a pressure indicator

  which measures the pressure of the fluid under pressure Then,

  ali-er-te the y-auiique cylinder, for example by 10% of -l

  control pressure and the indicator 54 is set to zero.

  We can then perform the control (the test) itself.

  i C by increasing the hydraulic pressure up to the pressure

  test time The stopwatch 54 then indicates the elongation

  specimen between the initial tractin (in the pre-

  feel, 10% of the test drive stuffing) and the strength of

test pull.

  -5 When the traction element is in the unloaded state

  and that the catches are contracted, the

  positive and place it on the next specimen.

  For the purposes of adaptation to specific

  of variable length, tubular extensions which, as indicated in indents, can be screwed into

  the support ring and extend it in the axial direction.

  The device for testing the tensile strength shown in FIG. 2 comprises a hydraulic cylinder 61 calculated for example for a pressure of 1000 bar. Screws on the hydraulic cylinder are inferiorly

  a hollow support 62, and more particularly a fork 63 comprising

  a handle on the upper side of the hydraulic cylinder

  that 61 is further detachably secured by means of a

  clamp 66, an indicator mount 65 The cylinder

  Hydraulic head 61 comprises a piston 67 provided with a bore

  axial in which is introduced an assembly bolt 68.

  The assembly bolt 68 comprises a rod 69 which passes through the bore of the piston 67 and a head 70 of enlarged diameter which

  rests on the upper end of the piston 67 via

of a disc 71 interposed.

  The tensile strength test device and

  drawing 60 according to Fig. 2 is used as follows.

  After having welded a bolt 3 to the piece 1, the hydraulic cylinder 61 is placed with the hollow support 62 on the bolt to be controlled. The mount 65 is then not yet installed. The assembly bolt 68 is then introduced from above. in

  the bore of the hydraulic piston 67 and is screwed on the

  lon 3 by a tapped hole 72 practiced inferiorly in the rod 69, which is done by means of a lever 73 that one

  placed in a hole 74 made in the head 70 of the bolt

  Then, the mount 65 is placed on which is an indicator 74 and is blocked by means of the handle 66 is then sent into the hydraulic cylinder 61 a fluid under pressure (not shown), which pushes the piston 67 to the top and makes act a corresponding pulling force on the threaded bolt 3 through the disc 71 and the assembly bolt 68 can read the degree of deformation

  plastic (stretching) then occurring on the indicator 74.

  After the tensile strength and / or drawing test of the

  threaded bolt 3, the device 70 is removed again

  screwing the bolt assembly 68 of the threaded bolt 3 and into

moving away the device.

  Instead of the device comprising the hydraulic cylinder

  that 61 and the piston 67, one can also use here another

  device, for example actuated mechanically or pneumatically-

  to generate a force between the bolt

68 and Exhibit 1.

Claims (8)

  1 Test device for tensile strength and   drawing for bolts protruding from a surface,   characterized in that it comprises a traction device (20, 26) which can be coupled to the bolt (19), a support device (36, 38) which can be placed on the surface (18) and a mechanism (48, 50) for generating a force between the device of traction and the support device.   2 Device according to claim 1, characterized in that the mechanism (48,50) generating the forces comprises a pressurized fluid cylinder.   Device according to claim 1 or 2, characterized   in that the traction device comprises an assembly bolt (26) connected to the mechanism generating forces   (48,50), as well as engaging elements (20) coupled to the   ci so as to be able to move radially, which can be   mated to a test specimen (19,59).   4 Device according to claim 3, characterized in that the assembly bolt (26) has a protruding flange (24) which penetrates into the grooves (22) of the gripping elements,   in that the gripping elements (20) are placed with sur-   oblique outer faces (30) in a sleeve (34) axially displaceable in a housing (36) which has inner surfaces of corresponding oblique shape and which can be biased by a spring arrangement (40) in a closed position, and in that it comprises between the gripping elements (20) and the connecting bolt (26) a spring arrangement   (28) recalling the elements of grip in a position of   Verture. 5 Device according to claim 4, characterized in that the movable sleeve (34) is connected to sockets (42) which   protrude through axial slots (44) in the housing   tier (36), and in that other sockets (46) are placed on the housing (36) between the sockets (42) connected to the sleeve and a   support ring (38) placed at the end of the housing.   Device according to any one of the claims   preceding, characterized in that it comprises a device   measuring (54) for measuring the travel of the traction device.   7 Device according to claim 6, characterized ei)   the measuring device includes a displacement indicator   cement (54) having a rod-like feeler (56) which joins the specimen through an axial recess in the pulling device.   8 Device according to claims 6 and 7, characterized   characterized in that it comprises a transparent hollow cylinder   turning the measuring device (54).