Multi-bolt tightening sequence and fit correlation test device

Abstract

The present invention discloses a device for testing the correlation between the tightening sequence and fit of multiple bolts, comprising: a tightening torque meter and a preload force detector, a connected parts group, multiple groups of bolts to be tested, a fixture, and an information acquisition and display device. The connected parts group is positioned and fixed in the fixture, multiple groups of bolts to be tested are connected to the connected parts group, and each bolt to be tested includes a screw rod and a nut threadedly connected to the outer circle of the screw rod. The tightening torque meter is located above the bolt to be tested, and is used to apply torque to the bolt and nut to be tested and transmit torque force information to the information acquisition and display device. The preload force detector is connected to the screw rod of the bolt to be tested, and is used to obtain the preload force information of the screw rod and transmit it to the information acquisition and display device. The device of the present invention can be used to study and measure the changes in the preload force of other bolts caused by changes in various tightening conditions of different bolts, so that the preload force can be accurately controlled, and the reliability of the connecting bolt group of the aircraft engine rotor system can be improved.

Description

Technical Field

[0001] The present invention relates to the field of assembly technology, in particular to a device for testing the correlation between tightening sequence and fit of multiple bolts. Background Art

[0002] To address the common technical issues of large deviations in thread preload and insufficient assembly process stability in traditional torque methods, and to meet the high-precision threaded connection requirements of the next-generation aero-engine, particularly the service performance goals of low vibration, long life, and high reliability, this study, focusing on a high-pressure rotor in an aero-engine, explored tightening process methods for key threaded fasteners and established advanced thread tightening technology standards. This is crucial and urgent for model application verification. However, since bolt connections within aero-engines lack the aid of accessories such as gaskets, the tightening of adjacent bolts significantly interferes with intermediate bolts. Existing bolt tightening test equipment can only test the preload of a single bolt at a time, making it impossible to study the mutual interference between adjacent bolt groups.

[0003] When testing on an existing bolt tightening test bench, the test piece is first fixed on the test bench, then the bolt is passed through the test piece, and a nut is screwed onto the bolt. The nut is tightened by an electric tightening shaft, and finally the pre-tightening force is measured by a force sensor or an ultrasonic sensor to obtain a single bolt tightening curve.

[0004] Existing testing equipment has this flaw: Traditional bolt tightening test equipment can only tighten a single bolt and study the relationship between torque, angle of rotation, and preload. However, in flange parts, tightening a single bolt will also affect the already tightened bolts. This effect is called elastic interaction between bolts. The closer the two bolts are, the greater the elastic interaction between the bolts. Therefore, it is necessary to study the mutual influence of preload between adjacent bolts or spaced bolts. However, because the bolted connections inside aircraft engines are not assisted by accessories such as gaskets, the tightening of adjacent bolts has a relatively serious interference with the middle bolt. The elastic interaction between bolts is an important component affecting the bolted connections of aircraft engines. Studying only the influence of a single bolt on the connection is relatively limited. Summary of the Invention

[0005] The present invention provides a multi-bolt tightening sequence and fit correlation test device to solve the technical problem that the existing bolt tightening test device can only perform a tightening test on a single bolt at the same time to test the preload force and cannot study the mutual interference between adjacent bolt groups.

[0006] The technical solution adopted in the present invention is as follows:

[0007] A device for testing the correlation between tightening sequence and fit of multiple bolts, comprising: a tightening torque meter and a preload force detector, a connected parts group for simulating the actual installation condition of the bolts, multiple groups of tested bolts for testing, a fixture for installing the connected parts group, and an information collection and display device for displaying torque and preload force, wherein the tightening torque meter and the preload force detector are respectively connected to the information collection and display device; the fixture is fixedly supported on a test bench, the connected parts group is positioned and fixed in the fixture, multiple groups of tested bolts are connected to the connected parts group in sequence and at intervals, and each tested bolt includes a screw rod passing through the connected parts group and a nut threadedly connected to the outer circle of the extended end of the screw rod extending out of the connected parts group; the tightening torque meter is located above the tested bolt and is used to apply torque to the tested bolt nut and transmit torque force information to the information collection and display device; the preload force detector is connected to the screw rod of the tested bolt and is used to obtain preload force information on the screw rod and transmit it to the information collection and display device.

[0008] Furthermore, the connected parts group includes an upper connected part, a middle connected part and a lower connected part stacked up in sequence, and the screw of the bolt to be tested is threaded through and connected to the lower connected part, the middle connected part and the upper connected part from bottom to top, and then extends out, and the nut thread is installed on the outer circle of the protruding end of the screw; the clamp includes a clamp body and multiple groups of fasteners, and the clamp body is provided with a receiving groove for accommodating and positioning the connected parts group, the connected parts group is positioned and installed in the receiving groove, and is detachably fixed to the clamp body by multiple groups of fasteners.

[0009] Furthermore, the connected member group is a sector segment formed by circumferentially cutting a circular ring; and the accommodating groove is a sector groove adapted to the sector segment.

[0010] Furthermore, the clamp body includes a mounting plate and two legs connected to both sides of the mounting plate; the accommodating groove is formed by the inward concave processing of the upper surface of the mounting plate, and the bottom of the accommodating groove is also provided with a through-set window so that the bolt head of the screw is exposed from the bottom of the mounting plate; the accommodating groove and the window are both notched grooves formed by cutting a notch along the axial direction of the mounting plate, so that the connected component group is partially exposed.

[0011] Furthermore, the preload force detector includes an ultrasonic preload force sensor that uses ultrasonic waves to measure preload force information, and an ultrasonic probe holder for installing the ultrasonic preload force sensor; the ultrasonic preload force sensor is installed on the ultrasonic probe holder, and the ultrasonic probe holder is connected to the bolt head of the screw so that the ultrasonic preload force sensor presses against the end face of the bolt head, and the output end signal line of the ultrasonic preload force sensor passes through the ultrasonic probe holder and is connected to the information acquisition and display device.

[0012] Furthermore, the ultrasonic probe holder is a magnetic part with magnetism, which is provided with a first inner groove formed by the inward concave top surface, a first mounting hole formed by the inward concave bottom of the first inner groove, and a first wire groove processed through the bottom of the first mounting hole; the first inner groove is sleeved and connected to the bolt head of the screw; the ultrasonic preload force sensor is positioned and installed in the first mounting hole, and its output end signal line passes through the first wire groove and extends out to connect to the information acquisition and display device.

[0013] Furthermore, the preload force detector includes a force sensor installed on the outer circle of the screw to obtain preload force information. The force sensor is installed in the connected parts group, and its output end signal line passes through the connected parts group and is connected to the information acquisition and display device.

[0014] Furthermore, the middle connected part is provided with a second inner groove and a second wire groove formed by inward concave processing on its surface, and a second mounting hole is formed by inward concave processing on the bottom of the second inner groove and is set through, and the second wire groove is connected to the second inner groove; the force sensor is positioned and installed in the second inner groove, and its output end signal line is accommodated in the second wire groove, and is connected to the information acquisition and display device after being transmitted out of the second wire groove; the screw rod of the bolt to be measured is passed through the second inner groove and the second mounting hole.

[0015] Furthermore, the tightening torque meter includes an electric tightening shaft, a dynamic torque sensor and a nut tightening sleeve connected in sequence; the information acquisition and display device is a sensor acquisition card, and the dynamic torque sensor and the preload force detector are respectively connected to the sensor acquisition card.

[0016] Furthermore, the tightening torque meter includes a torque wrench and a nut tightening sleeve connected in sequence; the information acquisition and display device includes a first digital display screen built into the torque wrench and an external second digital display screen, and the preload force meter is connected to the second digital display screen.

[0017] The present invention has the following beneficial effects:

[0018] When the test device of the present invention is used to perform a bolt tightening test, a separate tightening method of tightening a single variable bolt in sequence (to study the influence of tightening a single variable bolt on the change of the pre-tightening force of the reference bolt) or a parallel tightening method of tightening multiple variable bolts in sequence and simultaneously (to study the influence of tightening multiple variable bolts simultaneously on the change of the pre-tightening force of the reference bolt) can be used to study and measure the changes in the pre-tightening force of other bolts (reference bolts in the present invention) caused by changes in various tightening conditions of different bolts. This solves the technical problem in the prior art that only a single bolt can be tightened at the same time and the mutual interference between adjacent bolt groups cannot be studied. The pre-tightening force of the bolt can be accurately controlled, and the reliability of the connecting bolt group of the aircraft engine rotor system can be improved, which is of great significance to ensuring the reliability of the threaded connection of the aircraft engine rotor.

[0019] In addition to the above-described objects, features and advantages, the present invention has other objects, features and advantages. The present invention will be further described in detail below with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The accompanying drawings, which constitute part of this application, are intended to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are intended to explain the present invention and do not constitute an undue limitation of the present invention. In the accompanying drawings:

[0021] Figure 1 1 is a partial cross-sectional front view of a first embodiment of a test device for correlation between tightening sequence and fit of multiple bolts according to the present invention;

[0022] Figure 2 yes Figure 1 Schematic diagram of the spatial structure of the middle fixture body;

[0023] Figure 3 yes Figure 1 A schematic diagram of the partial cross-sectional spatial structure of the ultrasound probe holder;

[0024] Figure 4 1 is a partial cross-sectional front view of a second embodiment of a test device for correlation between tightening sequence and fit of multiple bolts according to the present invention;

[0025] Figure 5 yes Figure 4 Schematic diagram of the top view of the connected parts in the middle layer;

[0026] Figure 6 yes Figure 5 AA-direction cross-sectional structural diagram;

[0027] Figure 7 This is a partial cross-sectional front view of the structure of Example 3 of the multi-bolt tightening sequence and fit correlation test device of the present invention.

[0028] 1. Tightening torque meter; 11. Electric tightening shaft; 12. Dynamic torque sensor; 13. Nut tightening sleeve; 14. Torque wrench; 2. Preload force detector; 21. Ultrasonic preload force sensor; 22. Ultrasonic probe holder; 221. First inner groove; 222. First mounting hole; 223. First wire groove; 23. Force sensor; 3. Connected parts group; 31. Upper connected parts; 32. Middle connected parts; 321. Second inner groove; 322. Second mounting hole; 323. Second wire groove; 33. Lower connected parts; 4. Bolt to be measured; 41. Screw; 42. Nut; 5. Clamp; 51. Clamp body; 511. Receiving groove; 512. Window; 52. Fastener; 6. Information acquisition and display device; 61. Sensor acquisition card; 62. Second digital display screen. DETAILED DESCRIPTION

[0029] The embodiments of the present invention are described in detail below with reference to the accompanying drawings. However, the present invention can be implemented in many different ways as defined and covered below.

[0030] Reference Figure 1 、 Figure 4 and Figure 7 A preferred embodiment of the present invention provides a test device for the correlation between tightening sequence and fit of multiple bolts, comprising: a tightening torque meter 1 and a preload force detector 2; a connected component group 3 for simulating actual bolt installation conditions; multiple groups of tested bolts 4 for testing; a fixture 5 for mounting the connected component group 3; and an information acquisition and display device 6 for displaying torque and preload. The tightening torque meter 1 and the preload force detector 2 are each connected to the information acquisition and display device 6. The fixture 5 is fixedly supported on a test bench, the connected component group 3 is positioned and fixed in the fixture 5, and multiple groups of tested bolts 4 are sequentially connected to the connected component group 3 at intervals. Each tested bolt 4 includes a screw 41 extending through the connected component group 3 and a nut 42 threadedly connected to the outer diameter of the end of the screw 41 extending out of the connected component group 3. The tightening torque meter 1 is located above the tested bolt 4 to apply torque to the nut 42 of the tested bolt 4 and transmit torque information to the information acquisition and display device 6. The preload force detector 2 is connected to the screw rod 41 of the bolt 4 to be tested, so as to obtain the preload force information applied to the screw rod 41 and transmit the information to the information acquisition and display device 6 .

[0031] When the test device of the present invention is used to perform a bolt tightening test, the connected component group 3 is first installed and positioned in the fixture 5, and then multiple bolts 4 to be tested are connected to the connected component group 3 in sequence and at intervals to simulate the actual installation condition of the bolts. During the connection process of the bolts 4 to be tested, the preload force meter 2 is connected to one of the bolts 4 to be tested, so that the bolt 4 to be tested forms a reference bolt, and the remaining bolts 4 to be tested form variable bolts; then the tightening torque meter 1 and the preload force meter 2 are connected to the information acquisition and display device 6, and the preload force meter 2 is turned on. Then start the test. First, connect the tightening torque meter 1 to the nut of the reference bolt and gradually apply the target torque T. When the target torque T is reached, the target torque T and the preload force F are displayed and recorded on the information acquisition and display device 6. Then, remove the tightening torque meter 1 from the nut of the reference bolt and connect it to the nut of one of the variable quantity bolts. Then start the tightening torque meter 1 to apply the target torque T. When the target torque T is reached, the target torque T and the preload force F1 are displayed and recorded on the information acquisition and display device 6 (because the preload force detector 2 is always connected to the reference bolt, F1 is the preload force applied to the reference bolt). Then, use the same method to measure the remaining variable quantity bolts in sequence. bolts to obtain target torque T and pre-tightening force F2, target torque T and pre-tightening force F3, ... target torque T and pre-tightening force Fn; or, the tightening torque meter 1 is removed from the nut of the reference bolt and then connected to the nuts of multiple variable bolts at the same time, and then the tightening torque meter 1 is started to apply the target torque T. When the target torque T is reached, the target torque T and pre-tightening force F1 are displayed and recorded by the information acquisition and display device 6, and then the remaining variable bolts are measured in the same way (at least two groups of variable bolts are connected for each measurement) to obtain target torque T and pre-tightening force F2, target torque T and pre-tightening force F3, ... target torque T and pre-tightening force Fm.

[0032] When the test device of the present invention is used to perform a bolt tightening test, a separate tightening method of tightening a single variable bolt in sequence (to study the influence of tightening a single variable bolt on the change of the pre-tightening force of the reference bolt) or a parallel tightening method of tightening multiple variable bolts in sequence and simultaneously (to study the influence of tightening multiple variable bolts simultaneously on the change of the pre-tightening force of the reference bolt) can be used to study and measure the changes in the pre-tightening force of other bolts (reference bolts in the present invention) caused by changes in various tightening conditions of different bolts. This solves the technical problem in the prior art that only a single bolt can be tightened at the same time and the mutual interference between adjacent bolt groups cannot be studied. The pre-tightening force of the bolt can be accurately controlled, and the reliability of the connecting bolt group of the aircraft engine rotor system can be improved, which is of great significance to ensuring the reliability of the threaded connection of the aircraft engine rotor.

[0033] Alternatively, as Figure 1 、 Figure 4 and Figure 7As shown, the connected parts group 3 includes an upper connected part 31, a middle connected part 32 and a lower connected part 33 stacked up in sequence, and the screw rod 41 of the tested bolt 4 is threadedly passed through the lower connected part 33, the middle connected part 32 and the upper connected part 31 from bottom to top and then extends out, and the nut 42 is threadedly mounted on the outer circle of the protruding end of the screw rod 41.

[0034] Recombination Figure 2 As shown, the fixture 5 includes a fixture body 51 and multiple sets of fasteners 52. The fixture body 51 is provided with a receiving groove 511 for accommodating and positioning the connected component group 3. The connected component group 3 is positioned and installed in the receiving groove 511 and is detachably fixed to the fixture body 51 by multiple sets of fasteners 52. During installation, the upper connected component 31, the middle connected component 32, and the lower connected component 33 are first fixed and overlapped using fasteners 52. Then, multiple pairs of tested bolts 4 are installed on the connected component group 3 and the nuts 42 are pre-tightened by manual tightening. Due to the relatively high positioning tolerance requirements of the bolt holes, the fasteners 52 should be used first. In the present invention, fastening screws are used to install and position them, and then other tested bolts 4 are installed. Finally, the entire connected component group 3 is installed on the fixture 5 using fastening screws. In other embodiments, the form of the fixture 5 is not limited to the connection method shown in this application. A fixture that can grasp multiple bolt simulation parts, such as a bench vise or a three-jaw chuck, can also be used.

[0035] Preferably, if Figure 2 and Figure 5 As shown, the connected component group 3 is a fan-shaped segment formed by circumferential cutting of a circular ring. The accommodating groove 511 is a fan-shaped groove adapted to the fan-shaped segment. During design, in order to study the elastic interaction between flange bolts, the best way is to manufacture a flange simulation part, and then conduct a simulated tightening experiment on the simulation part to analyze the influence of the elastic interaction between the bolts. However, for large-diameter flanges, the cost of directly processing the simulation part is extremely high, and the structure of some flanges is complex. Conducting simulation experiments after processing will cause unnecessary waste. Therefore, it is necessary to invent a structure that can simulate the state of tightening multiple bolts without processing the entire flange, and at the same time can complete the collection requirements of preload force-torque-angle for studying the elastic interaction between bolts. Thus, the structural setting "the connected component group 3 is a fan-shaped segment formed by circumferential cutting of a circular ring" appears to solve this problem.

[0036] Specifically, when designing the connected component group 3, the inner and outer diameters of the connected component group 3 are consistent with those of the flange mounting edge, and the thickness of the connected component group 3 is the same as the thickness of the flange mounting edge. However, the connected component group 3 is designed to have only a few bolt holes in a sector shape, simplifying the other structures of the flange mounting edge. This not only maintains experimental accuracy but also saves experimental materials and reduces costs. In other embodiments, the shape of the connected component group 3 is not limited to a sector shape and can also be rectangular, irregular, or other shapes that are fastened to multiple bolts on parts such as flanges and cylinder blocks.

[0037] Alternatively, as Figure 1-2 As shown, the fixture body 51 comprises a mounting plate and two legs connected to either side of the mounting plate. A receiving groove 511 is formed by a recessed process in the upper surface of the mounting plate. A window 512 is also provided at the bottom of the receiving groove 511, allowing the bolt head of the screw 41 to be exposed through the bottom of the mounting plate. Both the receiving groove 511 and the window 512 are notches formed by axially cutting through the mounting plate, allowing a portion of the connected component group 3 to be exposed for observation. The legs are secured with anchor bolts.

[0038] Optionally, the first embodiment of the preload force detector 2, such as Figure 1 and Figure 3 As shown, the preload force detector 2 includes an ultrasonic preload force sensor 21 that uses ultrasonic waves to measure preload force information, and an ultrasonic probe holder 22 for mounting the ultrasonic preload force sensor 21. The ultrasonic preload force sensor 21 is mounted on the ultrasonic probe holder 22, which is connected to the bolt head of the screw 41 so that the ultrasonic preload force sensor 21 presses against the end face of the bolt head. The output signal line of the ultrasonic preload force sensor 21 passes through the ultrasonic probe holder 22 and is connected to the information acquisition and display device 6.

[0039] In this option, if Figure 1 and Figure 3 As shown, the ultrasonic probe holder 22 is a magnetic component with a magnetic property. It is provided with a first inner groove 221 formed by an inward concave top surface, a first mounting hole 222 formed by an inward concave bottom of the first inner groove 221, and a first wire groove 223 machined through the bottom of the first mounting hole 222. The first inner groove 221 is sleeved and connected to the bolt head of the screw 41. The ultrasonic preload force sensor 21 is positioned and mounted in the first mounting hole 222, and its output signal line passes through the first wire groove 223 and then extends to connect to the information acquisition and display device 6. In this embodiment, the ultrasonic probe holder 22 tightly connects the ultrasonic preload force sensor 21 to the bolt head of the bolt 4 being measured, ensuring real-time measurement of the preload force.

[0040] Optionally, the second embodiment of the preload force detector 2 is as follows: Figure 4-Figure 7As shown, the preload force detector 2 includes a force sensor 23 installed on the outer circle of the screw 41 to obtain preload force information. The force sensor 23 is installed in the connected component group 3, and its output end signal line passes through the connected component group 3 and is connected to the information acquisition and display device 6.

[0041] In this option, if Figure 5-6 As shown, the middle connected part 32 is provided with a second inner groove 321 and a second wire groove 323 formed by the inner concave processing of the surface thereof, and a second mounting hole 322 is formed by the inner concave processing of the groove bottom of the second inner groove 321 and is provided through, and the second wire groove 323 is connected to the second inner groove 321. The force sensor 23 is positioned and installed in the second inner groove 321, and its output end signal line is accommodated in the second wire groove 323, and is connected to the information acquisition and display device 6 after passing through the second wire groove 323. The screw of the bolt 4 to be tested is provided through the second inner groove 321 and the second mounting hole 322. Preferably, as Figure 5-6 As shown, in the second embodiment of the preload force meter 2, a force sensor 23 is installed on the outer circle of the screw 41 of each group of measured bolts 4, and a second inner groove 321, a second mounting hole 322 and a second wire groove 323 are correspondingly provided on the middle connected part 32. Therefore, when replacing a different reference bolt for measurement, there is no need to disassemble the connected part group 3, thereby improving measurement efficiency and reducing operating steps.

[0042] The second embodiment of the preload force detector 2 differs from the first embodiment in that, in the second embodiment, a force sensor 23 is placed in a hole in the middle-layer connected component 32. The force sensor 23 is connected to the information acquisition and display device 6 via an output signal line. The preload force generated when the bolt is tightened is converted into an electrical signal by the force sensor 23. The electrical signal is then converted into the amount of bolt preload force by the information acquisition and display device 6, thereby obtaining the change in the reference bolt preload force during the tightening process of multiple bolts 4 being tested. In other words, the force sensor 23 replaces the ultrasonic preload force sensor 21 to measure the bolt preload force. Compared with the first embodiment, the second embodiment has the following disadvantages:

[0043] 1) The middle connected member 32 needs to be designed with a second inner groove 321 for mounting the force sensor 23, so the design of the middle connected member 32 is relatively complex;

[0044] 2) Due to the size limitation of the force sensor 23, the sizes of the bolt 4, upper connected part 31, middle connected part 32, and lower connected part 33 cannot be too small. Therefore, it is impossible to measure too small bolts and flange mounting edges.

[0045] 3) The force sensor 23 needs to be installed in the middle connected component 32 in advance. For a multi-bolt structure, there must be as many force sensors 23 as there are bolts 4 to be tested. Compared with the ultrasonic preload force sensor 21, the experimental cost is increased.

[0046] Compared with the first embodiment, the second embodiment has the following advantages:

[0047] The multiple force sensors 23 simultaneously measure the forces of the multiple bolts 4 to be measured, and the comparison is more accurate and comprehensive.

[0048] Alternatively, tighten the first embodiment of the torque meter 1, such as Figure 1 and Figure 4 As shown, the tightening torque meter 1 includes an electric tightening shaft 11, a dynamic torque sensor 12 and a nut tightening sleeve 13 connected in sequence. In this optional solution, the inner surface of the lower end of the nut tightening sleeve 13 is consistent with the outer surface of the nut 42 to be measured. The lower end of the nut tightening sleeve 13 is sleeved on the nut 42, and the upper end is connected to the output end of the electric tightening shaft 11 through a flexible coupling; the dynamic torque sensor 12 is installed between the electric tightening shaft 11 and the nut tightening sleeve 13. Adaptively, the first embodiment of the information acquisition and display device 6, such as Figure 1 and Figure 4 As shown, the information acquisition and display device 6 is a sensor acquisition card 61 , and the dynamic torque sensor 12 and the preload force detector 2 are respectively connected to the sensor acquisition card 61 .

[0049] Alternatively, tighten the second embodiment of the torque meter 1, such as Figure 7 As shown, the tightening torque meter 1 includes a torque wrench 14 and a nut tightening sleeve 13 connected in sequence. Figure 7 As shown, the information collection and display device 6 includes a first digital display screen built into the torque wrench 14 and an external second digital display screen 62 , and the preload force detector 2 is connected to the second digital display screen 62 .

[0050] The second embodiment consisting of the tightening torque meter 1 and the information collection and display device 6 differs from the first embodiment consisting of the tightening torque meter 1 and the information collection and display device 6 in that:

[0051] 1) The electric tightening shaft 11 is replaced by a torque wrench 14. The torque wrench 14 has a digital display screen that can display the size of the tightening torque. The tester can record the torque size when the bolt is tightened.

[0052] 2) By placing a force sensor 23 in a groove in the middle layer of the connecting member 32, the force sensor 23 is connected to the second digital display screen 62 through the output signal line. The second digital display screen 62 can directly display the size of the pre-tightening force of the force sensor 23, but cannot record the process quantity. It can only record the final value of the pre-tightening force of the force sensor 23 after each tightening step.

[0053] 3) The torque is controlled by replacing the electric tightening shaft 11 with the torque wrench 14 and the input torque is recorded. The bolt pre-tightening force value is recorded by replacing the ultrasonic pre-tightening force sensor 21 with the force sensor 23 .

[0054] The second embodiment consisting of the tightening torque meter 1 and the information collection and display device 6 has the following disadvantages compared to the first embodiment consisting of the tightening torque meter 1 and the information collection and display device 6:

[0055] 1) The accuracy of the torque wrench 14 is less than that of the electric tightening shaft 11;

[0056] 2) Data acquisition is not performed through a data acquisition card, but rather through a first digital display on the torque wrench 14 and a second digital display 62 connected to the force sensor 23. Through the first and second digital displays 62, we cannot obtain the process values ​​of torque and preload during the bolt tightening process, but only the stage values ​​of torque and preload.

[0057] 3) Similarly, the use of force sensors 23 is limited by the size of the sensor and cannot measure bolts that are too small. In addition, multiple force sensors 23 increase the design complexity of the middle-layer connected component 32.

[0058] The second embodiment consisting of the tightening torque meter 1 and the information collection and display device 6 has the following advantages over the first embodiment consisting of the tightening torque meter 1 and the information collection and display device 6:

[0059] The torque wrench 14 is used to replace the electric tightening shaft 11, and the digital display screen is used to replace the data acquisition card. Although the number of force sensors 23 is increased, the total cost is still greatly reduced.

[0060] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of protection of the present invention.

Claims

1. A multi-bolt tightening sequence and fit correlation test device, characterized in that: include: A tightening torque meter (1) and a preload force detector (2), a connected component group (3) for simulating an actual bolt installation condition, a plurality of groups of tested bolts (4) for testing, a fixture (5) for installing the connected component group (3), and an information acquisition and display device (6) for displaying torque and preload force, wherein the tightening torque meter (1) and the preload force detector (2) are respectively connected to the information acquisition and display device (6); The fixture (5) is fixedly supported on the test bench, the connected component group (3) is positioned and fixed in the fixture (5), and a plurality of groups of tested bolts (4) are sequentially connected to the connected component group (3) at intervals, and each tested bolt (4) includes a screw rod (41) passing through and connected to the connected component group (3), and a nut (42) threadedly connected to the outer circle of the extended end of the screw rod (41) extending out of the connected component group (3); The tightening torque meter (1) is located above the bolt (4) to be tested, and is used to apply torque to the nut (42) of the bolt (4) to be tested and transmit torque force information to the information collection and display device (6); The preload force detector (2) is connected to the screw rod (41) of the bolt (4) to be tested, so as to obtain the preload force information on the screw rod (41) and transmit it to the information acquisition and display device (6).

2. The multi-bolt tightening sequence and fit correlation testing device according to claim 1, characterized in that: The connected member group (3) comprises an upper connected member (31), a middle connected member (32) and a lower connected member (33) which are stacked up and down in sequence. The screw rod (41) of the tested bolt (4) is threadedly threaded through and connected to the lower connected member (33), the middle connected member (32) and the upper connected member (31) from bottom to top, and then extends out. The nut (42) is threadedly mounted on the outer circle of the extended end of the screw rod (41). The clamp (5) comprises a clamp body (51) and a plurality of sets of fasteners (52). The clamp body (51) is provided with a receiving groove (511) for receiving and positioning the connected component group (3). The connected component group (3) is positioned and installed in the receiving groove (511) and is detachably fixed to the clamp body (51) by the plurality of sets of fasteners (52).

3. The multi-bolt tightening sequence and fit correlation testing device according to claim 2, characterized in that: The connected component group (3) is a fan-shaped segment formed by circumferentially cutting a circular ring; The accommodating groove (511) is a fan-shaped groove adapted to the fan-shaped segment.

4. The multi-bolt tightening sequence and fit correlation testing device according to claim 2, characterized in that: The clamp body (51) includes a mounting plate and two legs connected to both sides of the mounting plate; The accommodating groove (511) is formed by concave processing on the upper surface of the mounting plate, and the bottom of the accommodating groove (511) is also provided with a window (512) provided therethrough, so that the bolt head of the screw rod (41) is exposed from the bottom of the mounting plate; The accommodating groove (511) and the window (512) are both notched grooves formed by cutting a notch in the axial direction of the mounting plate, so that the connected component group (3) is partially exposed.

5. The multi-bolt tightening sequence and fit correlation testing device according to claim 1, characterized in that: The preload force detector (2) includes an ultrasonic preload force sensor (21) for detecting preload force information using ultrasonic waves, and An ultrasonic probe holder (22) for mounting an ultrasonic preload force sensor (21); The ultrasonic preload force sensor (21) is mounted on the ultrasonic probe holder (22), and the ultrasonic probe holder (22) is connected to the bolt head of the screw rod (41) so that the ultrasonic preload force sensor (21) presses against the end face of the bolt head, and the output end signal line of the ultrasonic preload force sensor (21) passes through the ultrasonic probe holder (22) and is connected to the information acquisition and display device (6).

6. The multi-bolt tightening sequence and fit correlation testing device according to claim 5, characterized in that: The ultrasonic probe holder (22) is a magnetic component with magnetism, and is provided with a first inner groove (221) formed by an inward concave top surface, a first mounting hole (222) formed by an inward concave bottom of the first inner groove (221), and a first line groove (223) machined through the bottom of the first mounting hole (222); The first inner groove (221) is sleeved and connected to the bolt head of the screw rod (41); The ultrasonic preload force sensor (21) is positioned and installed in the first installation hole (222), and the output end signal line thereof passes through the first line groove (223) and then extends out to connect to the information collection and display device (6).

7. The multi-bolt tightening sequence and fit correlation testing device according to claim 2, characterized in that: The preload force detector (2) comprises a force sensor (23) mounted on the outer circle of a screw (41) to obtain preload force information. The force sensor (23) is mounted in a connected component group (3). An output signal line of the force sensor (23) passes through the connected component group (3) and is then connected to an information acquisition and display device (6).

8. The multi-bolt tightening sequence and fit correlation testing device according to claim 7, characterized in that: The middle connected member (32) is provided with a second inner groove (321) and a second wire groove (323) formed by inward concave processing on its surface, and a second mounting hole (322) formed by inward concave processing on the bottom of the second inner groove (321) and penetrating therethrough, and the second wire groove (323) is connected to the second inner groove (321); The force sensor (23) is positioned and installed in the second inner groove (321), and the output end signal line thereof is accommodated in the second line groove (323), and is connected to the information collection and display device (6) after being transmitted out of the second line groove (323); The screw rod of the tested bolt (4) is provided through the second inner groove (321) and the second mounting hole (322).

9. The multi-bolt tightening sequence and fit correlation testing device according to claim 1, characterized in that: The tightening torque meter (1) comprises an electric tightening shaft (11), a dynamic torque sensor (12) and a nut tightening sleeve (13) which are connected in sequence; The information acquisition and display device (6) is a sensor acquisition card (61), and the dynamic torque sensor (12) and the preload force detector (2) are respectively connected to the sensor acquisition card (61).

10. The multi-bolt tightening sequence and fit correlation testing device according to claim 1, characterized in that: The tightening torque meter (1) comprises a torque wrench (14) and a nut tightening sleeve (13) which are connected in sequence; The information collection and display device (6) comprises a first digital display screen built into the torque wrench (14) and an external second digital display screen (62), and the preload force detector (2) is connected to the second digital display screen (62).

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