Deep-sea high-pressure multi-strain-rate load test device and operation method

Abstract

The invention discloses a deep-sea high-pressure multi-strain-rate load test device and an operation method, and relates to the technical field of deep-sea load tests.The deep-sea high-pressure multi-strain-rate load test device comprises a base, a containing structure used for containing a test piece is arranged on the base, and a low-strain-rate load loading device used for stretching the test piece is arranged on the base; a dynamic impact structure for performing high strain rate impact on a test piece is arranged on the base, a pressurizing device is arranged below the base, the pressurizing device is used for injecting water into the accommodating structure and pressurizing the accommodating structure, and the pressurizing device can inject water into the accommodating structure, so that the water pressure in the accommodating structure is increased, and the water pressure in the accommodating structure is increased to a deep sea high-pressure environment; the low-strain-rate load loading device can enable the test piece to be stretched in various low-strain-rate states, and the dynamic impact structure is matched to spread high-strain-rate impact to the test piece, so that the test piece can be subjected to a combined test in a deep sea environment.

Description

Technical Field

[0001] This invention relates to the field of deep-sea load testing technology, and in particular to a deep-sea high-pressure multi-strain rate load testing device and its operation method. Background Technology

[0002] Deep-sea exploration equipment faces the challenge of deployment and retrieval during seabed operations. The deployment and retrieval cables are affected by several factors: First, the cables are subject to the complex marine environment of wind, waves, and currents. Even with dynamic positioning on the mother ship, heave, pitch, and roll movements still occur, resulting in periodic dynamic loads on the equipment. Second, frequent acceleration, deceleration, and restarts of the winch on the mother ship, as well as sudden changes in the landing and lifting speeds of the equipment, create impact dynamic loads in the deployment and retrieval system, causing cable strain rates to reach 10²–10⁴ s². -1 High strain rate condition.

[0003] The high strain rate mechanical properties of cables and their materials differ from conventional static and dynamic mechanical properties, requiring impact testing equipment to obtain. During the deployment and retrieval of deep-sea exploration equipment, especially when the equipment reaches depths of 10,000 meters, the cables must withstand long-term load-bearing operations under pressures of 0-110 MPa. The superimposed dynamic loads can severely affect the reliability of the equipment deployment and retrieval. Finally, it must be pointed out that the deployment and retrieval cables used for seabed exploration equipment are armored umbilical cables. The outer armor is for load-bearing and protection, while the internal cables and optical cables do not bear loads. Moreover, due to the inherent weight limitations of the cables, conventional steel wire rope armored cables cannot be used for deployment and retrieval of seabed exploration equipment exceeding 6,000 meters. Instead, high-strength, low-density non-metallic materials made of high-modulus synthetic fibers must be used for cable armor, which has viscoelastic properties. The deployment and retrieval time for deep-sea exploration equipment can range from several hours to tens of hours. Such long deployment and retrieval operations can cause creep effects in the cables made of high-modulus synthetic fibers.

[0004] In the deep sea, especially in the abyss environment at depths of 10,000 meters, the surrounding environmental pressure gradually increases with water depth. At the same time, high-elasticity, high-modulus cable materials and their structures are often under long-term creep and dynamic-static combined loading conditions. Conventional test devices generally use hydraulic oil to simulate the confining pressure environment and can only perform a single tensile loading method. There is no test device that meets the requirements of high-pressure water environment and allows for multiple loading combinations, especially in cases involving static creep, dynamic impact, and combined loading of dynamic impact loads and static prestressed tensile loads under ultra-high pressure water environment.

[0005] To address the above shortcomings, further improvements are needed to the load testing device to overcome the problem that it cannot test specimens in an ultra-high pressure water environment. Summary of the Invention

[0006] This invention aims to overcome the problem that load testing devices cannot test specimens in ultra-high pressure water environments, and provides a deep-sea high-pressure multi-strain rate load testing device and its operation method.

[0007] To achieve the above objectives, the present invention provides the following technical solution: a deep-sea high-pressure multi-strain rate load testing device, comprising a base, a housing structure for placing a specimen on the base, a low strain rate load loading device for tensile testing of the specimen on the base, a dynamic impact structure for impact testing of the specimen on the base, and a pressurizing device below the base for injecting water and pressurizing the interior of the housing structure.

[0008] As a further aspect of the present invention: the accommodating structure includes a vessel body, which is disposed on a base and connected to a low strain rate load loading device. A cable specimen is disposed inside the vessel body, and a clamp for fixing the cable specimen is disposed inside the vessel body. An exhaust port is provided on the vessel body, and a water inlet is provided at the bottom of the vessel body. A closing valve is provided above the exhaust port. A water injection pipe is provided at one end of the pressurizing device, and the end of the water injection pipe away from the pressurizing device is connected to the water inlet. A deformation sensor is provided on the vessel body.

[0009] As a further aspect of the present invention: the pressurizing device includes a driving component, one end of which is provided with a ball screw, the end of which is away from the driving component is connected to a water injection pipe, and a water pump is provided on one side of the ball screw, the outlet of which is connected to the water injection pipe.

[0010] As a further aspect of the present invention: the low strain rate load loading device includes a servo motor, the drive end of the servo motor is connected to a reduction gearbox, the end of the reduction gearbox away from the servo motor is connected to a threaded screw, a reflector is provided on the base, the end of the threaded screw away from the reduction gearbox is helically connected to the reflector, and the end of the reflector away from the threaded screw is threadedly connected to an impact rod.

[0011] As a further aspect of the present invention: a connecting hole is provided on the side of the vessel body near the impact rod, and an incident rod is connected to one end of the impact rod near the vessel body. One end of the incident rod passes through the connecting hole and is connected to the clamp. A transmission rod is provided on the base. The transmission rod is located on the side of the vessel body away from the incident rod. One end of the transmission rod is connected to the vessel body. A sealing ring is provided on the inner wall of the connecting hole, and the inner wall of the sealing ring abuts against the outer wall of the incident rod.

[0012] As a further aspect of the present invention: the dynamic impact structure includes a gun barrel, an air compressor pump is provided below the base, the gun barrel is sleeved on the firing rod, a hammer is sleeved on the firing rod, an air supply pipe is provided at the output of the air compressor pump, the end of the air supply pipe away from the air compressor pump is connected to the gun barrel, and the hammer is slidably connected to the firing rod.

[0013] As a further aspect of the present invention: the clamp consists of two connecting cylinders, with a cable specimen disposed between the two connecting cylinders. The ends of the two connecting cylinders that are far apart from each other are provided with threads, and a connecting hole is opened at the center of the two connecting cylinders. Both ends of the cable specimen are bonded to the inner wall of the connecting hole.

[0014] As a further aspect of the present invention: the clamp is a first connecting cylinder and a second connecting cylinder, the first connecting cylinder has a wire groove, the inner wall of the first connecting cylinder has a plurality of fixing rods, and the inner wall of the second connecting cylinder has a plurality of fixing holes that cooperate with the fixing rods.

[0015] As a further aspect of the present invention: the clamp consists of two connecting cylinders, with a cable test piece disposed between the two connecting cylinders. The cable test piece includes an outer sheath and a battery core. A cone is disposed inside each of the two connecting cylinders, and a through hole for the battery core to enter is opened at the axis of the cone. Both ends of the battery core pass through the cone, and the outer sheath is in contact with the surface of the cone. A hoop is disposed inside each of the two connecting cylinders, and the hoop is fitted onto the end of the cable test piece.

[0016] An operating method, applied to the deep-sea high-pressure multi-strain rate load testing device as described above, includes the following steps: S1: Fix the vessel body between the incident rod and the transmission rod, and the clamp fixes the cable specimen to the end of the incident rod; S2: The deformation sensor is directly clamped onto the cable specimen through the pre-drilled hole in the vessel body to measure the deformation of the specimen. S3: Use a water pump to add water to the vessel until water comes out of the vent hole on the vessel. The vessel is now full of water, indicating that the gas has been released. At this point, turn off the water pump. S4: Start the drive unit, set the pressure to the predetermined pressure value, and use the ball screw to pressurize the vessel. Once the pressure is reached, the pressure sensor reads the pressure and the drive unit drives the ball screw to stabilize the pressure in real time. S5: Turn on the servo motor and adjust the low strain rate load loading device to the predetermined static load value. The loading rate can be adjusted according to different needs of creep and static tension. S6: Under the same pressure, different magnitudes of stress are measured using force sensors of varying sizes, depending on the object being clamped by the fixture.

[0017] Compared with the prior art, the beneficial effects of this technical solution are as follows: the pressurization device can inject water into the interior of the container structure, thereby increasing the water pressure inside the container structure to the high pressure environment of the deep sea. The low strain rate load loading device can allow the specimen to undergo various low strain rate states of tension. Combined with the dynamic impact structure, the high strain rate impact can be propagated to the specimen, so that the specimen can be subjected to combined tests in the deep sea environment. The operation steps of this invention can be used to conduct creep or tensile tests on cable specimens in a deep-sea environment, and can also be used to conduct dynamic impact tests on cable specimens based on creep or tensile tests, thereby achieving the purpose of conducting composite tests on cable specimens.

[0018] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a top view of the overall structure of the present invention; Figure 3 This is a schematic diagram of the internal structure of the low strain rate load loading device of the present invention; Figure 4 This is a schematic diagram of the pressurization device of the present invention; Figure 5 This is a front view schematic diagram of the adhesive clamp of the present invention; Figure 6 yes Figure 5 Schematic diagram of the cross section at point AA; Figure 7 This is a front view schematic diagram of the clamping fixture of the present invention; Figure 8 yes Figure 7 Schematic diagram of the cross section at point BB; Figure 9 yes Figure 8 Schematic diagram of the separation effect of the first and second connecting cylinders; Figure 10 This is a front view schematic diagram of the combined clamp of the present invention; Figure 11 yes Figure 10Schematic diagram of the cross section at point CC. Detailed Implementation

[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] Example 1: This embodiment discloses a deep-sea high-pressure multi-strain rate load testing device. Please refer to [link / reference]. Figure 1-11 A deep-sea high-pressure multi-strain rate load testing device includes a base 1, a housing structure 4 for placing a specimen on the base 1, a low strain rate load loading device 2 for adjusting the load on the housing structure 4 on the base 1, a dynamic impact structure 3 for impacting the specimen on the base 1, and a pressurizing device 5 below the base 1. The pressurizing device 5 is used to pressurize the interior of the housing structure 4. The pressurizing device can inject water into the housing structure to increase the water pressure inside the housing structure, thus increasing the water pressure to the level of the deep-sea environment. The low strain rate load loading device can keep the specimen under tension, and together with the dynamic impact structure, the stress is transmitted to the specimen. In this way, the specimen can be subjected to combined tests in the deep-sea environment.

[0023] In some embodiments: the accommodating structure 4 includes a vessel body 41, which is mounted on the base 1 and connected to the low strain rate load loading device 2. A cable specimen 43 is disposed inside the vessel body 41, and a clamp 42 for fixing the cable specimen 43 is provided inside the vessel body 41. An exhaust port is provided on the vessel body 41, and a water inlet is provided at the bottom of the vessel body 41. A closing valve is provided inside the exhaust port. One end of the pressurizing device 5 is provided with a water injection pipe 51, and the end of the water injection pipe 51 away from the pressurizing device 5 is connected to the water inlet. A deformation sensor 411 is provided on the vessel body 41. The vessel body 41 is the core functional unit of the deep-sea high-pressure multi-strain rate load testing device, mainly used to accommodate the cable specimen 43, simulate the deep-sea high-pressure water environment, and monitor the deformation of the specimen under load and pressure coupling in real time. The vessel body 41 can be a first vessel body 412 and a second vessel body 412. The body 413 has a slide rail on the base 1. The second vessel body is slidably connected to the slide rail. A bidirectional stroke cylinder 45 is provided between the first and second vessels. The bidirectional stroke cylinder can drive the second vessel body away from or closer to the first vessel body. After the cable test piece 43 is placed between the first and second vessels, the bidirectional stroke cylinder can drive the second vessel body to move towards the first vessel body, so that the first and second vessels are closed and a sealed space is formed. The pressurizing device 5 can inject water into the water inlet through the water injection pipe 51, so that water can enter the vessel body. When the vessel body is full of water, some water will overflow from the vent. After the water overflows, the vent can be closed by the closing valve, so that the vessel body is sealed. At this time, the pressurizing device 5 can continue to inject water to increase the water pressure inside the vessel body, thereby simulating the deep sea environment.

[0024] Specifically: the pressurizing device 5 includes a drive component 52, one end of which is equipped with a ball screw 53. The end of the ball screw 53 away from the drive component 52 is connected to the water injection pipe 51. A water pump 54 is provided on one side of the ball screw 53. The outlet of the water pump 54 is connected to the water injection pipe 51. The water pump will deliver water from the external water source to the water injection pipe, allowing the water to enter the interior of the vessel along the water injection pipe. When the interior of the vessel is full of water, the flow between the water injection pipe and the water pump is closed by a water valve between the water injection pipe and the water pump. The drive component 52 is a high-precision servo motor. After the water valve is closed, the drive component can drive the ball screw to drive the helical transmission, so that the ball screw pushes the remaining water in the water injection pipe into the vessel in the manner of a syringe. The water will continue to enter the interior of the vessel, thereby increasing the water pressure inside the vessel.

[0025] In some embodiments, the low strain rate load loading device 2 includes a servo motor 21, the drive end of the servo motor 21 is connected to a reduction gearbox 22, the end of the reduction gearbox 22 away from the servo motor 21 is connected to a threaded screw 23, a reflector 24 is provided on the base 1, the end of the threaded screw 23 away from the reduction gearbox 22 is helically connected to the reflector 24, and the end of the reflector 24 away from the threaded screw is threadedly connected to an impact rod 25. The servo motor can drive the threaded screw to rotate, so that the threaded screw drives the reflector to move towards the reduction gearbox through the helically connected to the reflector. When the reflector moves, it will stretch the test specimen cable, thereby performing a tensile test on the test specimen cable.

[0026] More specifically: A connecting hole is provided on the side of the vessel body 41 near the impact rod 25. An incident rod 26 is connected to one end of the impact rod 25 near the vessel body 41. One end of the incident rod 26 passes through the connecting hole and is connected to the clamp 42. A transmission rod 44 is provided on the base 1. The transmission rod 44 is located on the side of the vessel body 41 away from the incident rod 26. One end of the transmission rod 44 is connected to the vessel body 41. A sealing ring is provided on the inner wall of the connecting hole. The inner wall of the sealing ring abuts against the outer wall of the incident rod 26. When the reflector moves, it will move the incident rod together, so that the incident rod can pull the clamp. The clamp will move one end of the cable specimen, thereby stretching the cable specimen.

[0027] In some embodiments: the dynamic impact structure 3 includes a barrel 31, an air compressor pump 32 is provided below the base 1, the barrel 31 is sleeved on the incident rod 26, and a hammer 33 is sleeved on the incident rod 26. An air supply pipe 321 is provided at the output of the air compressor pump 32, and the end of the air supply pipe 321 away from the air compressor pump 32 is connected to the barrel 31. The hammer 33 is slidably connected to the incident rod 26. The barrel 31 is started by the air compressor pump 32 to drive the hammer 33 to impact the impact rod connected to the incident rod with the air pressure set in the experiment. Part of the impact directly generates tensile stress wave, and the other part of the compressive stress wave propagates forward. The compressive stress wave is transmitted to the reflection rod and the low strain rate load loading device. At the end, the reflected tensile stress wave propagates along the incident rod away from the reflecting rod. The two parts of the tensile stress wave propagate along the incident rod to the cable specimen, thus performing dynamic tensile loading. When the tensile stress wave is transmitted to the incident rod and the end face of the cable specimen, due to the difference in wave impedance between the incident rod and the fixture, part of the tensile stress wave is reflected into a reflected compressive stress wave. The reflected compressive stress wave enters the incident rod and propagates away from the cable specimen. Part of the tensile stress wave passes through the cable specimen and enters the transmission rod, becoming a transmitted tensile stress wave, and continues to propagate along the transmission rod away from the cable specimen, thus achieving the effect of dynamic impact.

[0028] In some embodiments: the clamp 42 consists of two connecting cylinders 421, with a cable specimen 43 disposed between the two connecting cylinders 421. The ends of the two connecting cylinders 421 that are far apart from each other are threaded, and a connecting hole 423 is opened at the center of the two connecting cylinders 421. Both ends of the cable specimen 43 are bonded to the inner wall of the connecting hole 423. To fix the cable specimen inside the connecting cylinder, epoxy resin is applied to both ends of the cable specimen. After application, the two ends of the cable specimen are inserted into the connecting holes of the two connecting cylinders respectively, so that the epoxy resin contacts the inner wall of the connecting hole. Then, the position is left to wait for the epoxy resin to solidify. After the epoxy resin solidifies, the ends of the cable specimen will be fixed inside the connecting hole, thereby achieving the fixing of the cable specimen by the connecting cylinder.

[0029] The specific experimental procedure is as follows: After placing the cable test piece 43 between the first and second vessels, the second vessel can be moved towards the first vessel by a bidirectional stroke hydraulic cylinder, closing the space between the first and second vessels and forming a sealed space. At this time, the water pump is started, which delivers water from the external water source to the water injection pipe, allowing the water to flow into the vessel. When the vessel is full of water, the flow between the water injection pipe and the water pump is closed by a water valve. The drive component 52 is a high-precision servo motor. After the water valve is closed, the drive component can drive the ball screw screw transmission, which pushes the remaining water in the water injection pipe into the vessel like a syringe. The water continues to flow into the vessel, thereby increasing the water pressure inside the vessel. When the vessel is full of water, some water will overflow from the vent. After the water overflows, the vent can be closed by a closing valve, sealing the inside of the vessel and creating a deep-sea environment inside.

[0030] Restarting the servo motor can drive the screw to rotate, causing the screw to move towards the gearbox via a helical connection with the reflector. As the reflector moves, it will move the incident rod along with it, which will pull the clamp. The clamp will move one end of the cable specimen, thereby stretching the cable specimen. The deformation sensor can obtain the creep and static tension of the cable specimen under different water pressures.

[0031] The air compressor 32 starts the barrel 31 to drive the hammer 33 to impact the impact rod connected to the incident rod with the air pressure set in the test. Part of the impact directly generates tensile stress wave, while the other part of the compressive stress wave propagates forward. When the compressive stress wave reaches the end of the reflector rod and the low strain rate load loading device, it is reflected into incident tensile stress wave and propagates along the incident rod away from the reflector rod. The two parts of the incident tensile stress wave will propagate along the incident rod to the cable specimen, thus performing dynamic tensile loading. When the incident tensile stress wave reaches the end face of the incident rod and the cable specimen, due to the difference in wave impedance between the incident rod and the fixture, part of the incident tensile stress wave will be reflected into reflected compressive stress wave. The reflected compressive stress wave will enter the incident rod and propagate away from the cable specimen. Part of the incident tensile stress wave will pass through the cable specimen and enter the transmission rod to become a transmitted tensile stress wave, and continue to propagate along the transmission rod away from the cable specimen, thus achieving the effect of dynamic impact.

[0032] Example 2: The difference between this embodiment and Embodiment 1 is that the clamp 42 consists of a first connecting cylinder 424 and a second connecting cylinder 425. The first connecting cylinder 424 has a wire groove 4241, and its inner wall has multiple fixing rods 4242. The inner wall of the second connecting cylinder 425 has multiple fixing holes 4251 that mate with the fixing rods 4242. To fix the cable specimen, first place the end of the cable specimen into the wire groove of the first connecting cylinder. When the cable specimen is in the wire groove, part of the cable specimen will protrude from the wire groove. At this time, align the fixing holes on the second connecting cylinder with the fixing rods. After alignment, the second connecting cylinder... The cylinder is pushed towards the first connecting cylinder, so that the fixing rod enters the fixing hole, thereby allowing the first connecting cylinder and the second connecting cylinder to be connected together. After connection, the first connecting cylinder and the second connecting cylinder can be fixed by the clamp sleeve 4243 that matches the clamp. The fixing process of the clamp sleeve is as follows: after the first connecting cylinder and the second connecting cylinder are connected, the clamp sleeve is put on the first connecting cylinder and the second connecting cylinder. The shape of the first connecting cylinder and the second connecting cylinder after connection is conical, so that the clamp sleeve can be put on from the end with the smaller outer diameter of the clamp. After the sleeve is put on, the separation of the first connecting cylinder and the second connecting cylinder can be avoided.

[0033] Example 3: The difference between this embodiment and Embodiment 1 is that the clamp 42 consists of two connecting sleeves 426, with a cable test piece 43 positioned between them. The cable test piece 43 includes an outer sheath 431 and a battery core 432. Both connecting sleeves 426 have a conical body 4261 inside, with a through hole 4262 at the axis of the conical body 4261 for the battery core 432 to enter. Both ends of the battery core 432 penetrate the conical body 4261, and the outer sheath 431 contacts the surface of the conical body 4261. Both connecting sleeves 426 have a clamp 4263 inside, which is fitted onto the end of the cable test piece 43. To fix the cable test piece, the outer sheath and battery core at the end of the cable test piece are first separated. Insert the core into the through hole, and simultaneously allow the outer sheath to enter the gap between the connecting cylinder and the cone. After entering the through hole, the core will penetrate through the hole, and the outer sheath will also pass through the gap between the connecting cylinder and the cone to move to the other end of the cone. At this time, the outer sheath passing through the gap between the connecting cylinder and the cone can rewrap around the core that has penetrated the through hole to form a cable specimen, preventing the core from carrying the outer sheath through the through hole, thus achieving a preliminary fixing effect. Then, put the hoop on the end of the rewrapped cable specimen, apply epoxy resin after putting it on, and let it stand to solidify, so that the rewrapped core and outer sheath cannot be separated, ensuring the fixation of the cable specimen. After the cable specimen is fixed, install the clamp inside the reactor body.

[0034] Example 4: An operation method for a deep-sea high-pressure multi-strain rate load testing device, the specific steps of which are as follows: The first vessel is fixed to the base via a slide rail. The second vessel is placed on the slide rail and close to the first vessel. The cable specimen is placed horizontally at the central axis between the two vessels. First, the two ends of the clamp holding the cable specimen are connected to the incident rod and the transmission rod respectively, ensuring the cable axis is aligned. The bidirectional stroke cylinder is activated to drive the second vessel to move along the slide rail toward the first vessel until the first and second vessels are completely fitted together to form a sealed space. The clamp can be used according to the different requirements of the cable specimen. The clamp usage process in Example 1 is as follows: First, apply epoxy resin to both ends of the cable specimen. Then, insert both ends of the cable specimen into the connection holes of the two connecting cylinders respectively. Then, let the connecting cylinders stand and wait for the epoxy resin to solidify. To use Example 1... When using the second clamp for fixation, the end of the cable specimen can be placed into the wire groove of the first connecting cylinder. After placement, the fixing hole of the second connecting cylinder is aligned with the fixing rod. After alignment, the second connecting cylinder is pushed to combine the first and second connecting cylinders. Finally, the clamp is sleeved on the combined first and second connecting cylinders to make the first and second connecting cylinders fit tightly together, thereby clamping and fixing the cable specimen between the first and second connecting cylinders. When the clamp of embodiment three is used, the cable specimen is first separated into the outer sheath and the battery core. Then, the battery core is inserted into the through hole of the cone. The outer sheath will pass through the gap between the cone and the connecting cylinder and re-wrap the battery core. Then, the clamp is put on and coated with epoxy resin for curing.

[0035] The test method for creep and static tensile testing of cable specimens under high pressure includes the following steps: The specimen is connected to the incident rod and the transmission rod using a clamp; a high-pressure resistant, waterproof, and corrosion-resistant deformation sensor is directly clamped onto the specimen through a pre-drilled hole in the vessel body. The deformation sensor can be directly used to measure the deformation of the specimen; an electric hydraulic pump drives a bidirectional stroke cylinder to close the vessel body; water is added to the vessel body using a water pump until water flows out of the drain hole on the vessel body, indicating that the vessel body is full of water and the gas has been vented. At this point, the water pump is turned off, and a high-pressure gauge is connected to the high-pressure three-way valve on the water injection pipe. Then, a high-precision servo motor is turned on, and the pressure is set to the predetermined pressure value. The pressure inside the vessel body is pressurized by injection using a ball screw. Once the pressure is reached, the pressure sensor... The pressure is read and stabilized in real time by a ball screw pressurizing device driven by a high-precision servo motor. After the pressure inside the vessel is resolved, the servo motor is turned on, and the static load application device is adjusted to the predetermined static load value. The loading rate can be adjusted according to different needs of creep and static tension. During the test, the load is applied for a long time through a static low strain rate load application device connected to the reflector rod. The load is measured by two force sensors of different sizes and recorded in real time by the accompanying software. Under the same pressure, different stresses are applied by force sensors of different sizes depending on the clamping object of the tensile fixture. The deformation behavior and performance characteristics of the specimen are obtained by deformation sensor after continuous loading for a certain period of time. The creep / static tension under different water pressure values ​​are obtained, and the above is repeated.

[0036] The operation and testing method of high-pressure dynamic impact tensile testing includes the following: The specimen is connected between the incident rod and the transmission rod using a clamp; the high-pressure vessel is closed using an electric hydraulic pump to drive a bidirectional stroke cylinder; water is added to the high-pressure vessel using a water pump until water flows out of the drain hole on the vessel, indicating that the vessel is full and the gas has been released. At this point, the high-pressure three-way valve is closed, and a high-pressure gauge is connected to it; the high-precision servo motor is turned on, and the pressure is set to the predetermined value. The high-pressure vessel is pressurized using a ball screw pressurizing device. Once the pressure is reached, it is read by a pressure sensor, and the high-precision servo motor drives the ball screw to stabilize the pressure in real time. The barrel is started by an air compressor pump to drive the impact hammer to strike the impact rod connected to the incident rod at the test-set air pressure. Part of the stress wave directly generates a tensile stress wave, while the other part propagates forward as a compressive stress wave. The compressive stress wave is then transmitted to the incident rod and the low strain rate load loading device. When the specimen is placed at the end, the reflected tensile stress wave becomes an incident tensile stress wave and propagates along the incident rod in a direction away from the impact rod. The two parts of the incident tensile stress wave propagate along the incident rod and dynamically load the specimen. When the incident tensile stress wave is transmitted to the incident rod and the end face of the specimen, due to the inconsistency of the wave impedance between the incident rod and the fixture, part of the incident tensile stress wave is reflected into a reflected compressive stress wave and enters the incident rod and propagates along the incident rod in a direction away from the specimen. Part of the incident tensile stress wave passes through the specimen and enters the transmission rod as a transmitted tensile stress wave, and continues to propagate along the transmission rod in a direction away from the specimen. During the test, the incident tensile stress wave, reflected compressive stress wave and transmitted tensile stress wave signals are collected by four pairs of semiconductor strain gauges respectively pasted on the surface of the center position of the incident rod and the transmission rod. Based on the stress wave signals collected during the test, the dynamic tensile strength, tensile strain and tensile strain rate of the test specimen are obtained.

[0037] The operation and testing methods for static and dynamic combined tensile testing include the following: The specimen is connected between the incident rod and the transmission rod using a clamp; a high-pressure resistant, waterproof, and corrosion-resistant deformation sensor is directly clamped onto the specimen through a pre-drilled hole in the autoclave body for direct measurement of the specimen's deformation; the autoclave body is closed using an electric hydraulic pump to drive a bidirectional stroke cylinder; water is added to the autoclave body using a water pump until water flows out of the drain hole, indicating that the autoclave body is full and the gas has been vented. At this point, the water pump is turned off, and a high-pressure gauge is connected to the high-pressure three-way valve; the high-precision servo motor is turned on, and the pressure is set to the predetermined pressure value. The autoclave is pressurized using a ball screw pressurizing device. Once the pressure reaches the set value, a pressure sensor reads the reading, and a high-precision servo motor drives the ball screw pressurizing device to stabilize the pressure in real time. The servo motor is then activated, and the static load application device is adjusted to the predetermined static load value. During the test, a low-strain rate load loading device connected to a reflector rod applies a long-term load, which is measured by two force sensors of different sizes combined, and recorded in real time by accompanying software. Under the same pressure, different stresses are applied using force sensors of different sizes, depending on the object being clamped by the fixture. This stress is then continuously applied for a certain period, and the stress is measured by a deformation sensor. The deformation behavior and performance characteristics of the specimen are obtained. Under a certain pre-tension force, the barrel is started by an air compressor pump to drive the hammer to impact the impact rod connected to the incident rod with the air pressure set for the test. Part of the impact force directly generates tensile stress waves, while the other part of the compressive stress waves propagates forward. When the compressive stress waves reach the end of the incident rod and the low strain rate load loading device, they are reflected into incident tensile stress waves and propagate along the incident rod in a direction away from the reflecting rod. The two parts of the incident tensile stress waves propagate along the incident rod to dynamically tensile load the specimen. When the incident tensile stress waves reach the incident rod and the end face of the specimen, due to the incident rod and the fixture... Due to the inconsistency in wave impedance, some incident tensile stress waves are reflected as reflected compressive stress waves, which then enter the incident rod and propagate away from the specimen along the rod. Other incident tensile stress waves pass through the specimen and enter the transmission rod as transmitted tensile stress waves, continuing to propagate away from the specimen along the rod. During the test, four pairs of semiconductor strain gauges, respectively attached to the surfaces at the center of the incident and transmission rods, are used to collect signals of the incident tensile stress wave, reflected compressive stress wave, and transmitted tensile stress wave. Based on the stress wave signals collected during the test, the dynamic tensile strength, tensile strain, and tensile strain rate of the test specimen are obtained.

[0038] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. A deep-sea high-pressure multi-strain rate load testing device, characterized in that, The system includes a base (1), a housing structure (4) for placing a specimen on the base (1), a low strain rate load loading device (2) for tensile testing of the specimen on the base (1), a dynamic impact structure (3) for impact testing of the specimen on the base (1), and a pressurizing device (5) below the base (1). The pressurizing device (5) is used to pressurize the interior of the housing structure (4) with water. The pressurizing device (5) includes a drive component (52), one end of which is provided with a ball screw (53). The end of the ball screw (53) away from the drive component (52) is connected to a water injection pipe (51). A water pump (54) is provided on one side of the ball screw (53). The outlet of the water pump (54) is connected to the water injection pipe (51). The low strain rate load loading device (2) includes a servo motor (21). The drive end of the servo motor (21) is connected to a gearbox (22). The end of the gearbox (22) away from the servo motor (21) is connected to a threaded screw (23). A reflector (24) is provided on the base (1). The end of the threaded screw (23) away from the gearbox (22) is connected to the reflector (24) in a spiral connection. The end of the reflector (24) away from the threaded screw is connected to an impact rod (25).

2. The deep-sea high-pressure multi-strain rate load testing device according to claim 1, characterized in that, The accommodating structure (4) includes a vessel body (41), which is mounted on a base (1) and connected to a low strain rate load loading device (2). A cable test piece (43) is provided inside the vessel body (41). A clamp (42) for fixing the cable test piece (43) is provided inside the vessel body (41). An exhaust port is provided on the vessel body (41). A water inlet is provided at the bottom of the vessel body (41). A closing valve is provided above the exhaust port. A water injection pipe (51) is provided at one end of the pressurizing device (5). The end of the water injection pipe (51) away from the pressurizing device (5) is connected to the water inlet. A deformation sensor (411) is provided on the vessel body (41).

3. The deep-sea high-pressure multi-strain rate load testing device according to claim 2, characterized in that, The vessel body (41) has a connection hole on the side near the impact rod (25). The end of the impact rod (25) near the vessel body (41) is connected to an incident rod (26). One end of the incident rod (26) passes through the connection hole and is connected to the clamp (42). The base (1) is provided with a transmission rod (44). The transmission rod (44) is located on the side of the vessel body (41) away from the incident rod (26). One end of the transmission rod (44) is connected to the vessel body (41). The inner wall of the connection hole is provided with a sealing ring. The inner wall of the sealing ring abuts against the outer wall of the incident rod (26).

4. The deep-sea high-pressure multi-strain rate load testing device according to claim 1, characterized in that, The dynamic impact structure (3) includes a gun barrel (31), an air compressor pump (32) is provided below the base (1), the gun barrel (31) is sleeved on the firing rod (26), a hammer (33) is sleeved on the firing rod (26), an air supply pipe (321) is provided at the output of the air compressor pump (32), the end of the air supply pipe (321) away from the air compressor pump (32) is connected to the gun barrel (31), and the hammer (33) and the firing rod (26) form a sliding connection.

5. The deep-sea high-pressure multi-strain rate load testing device according to claim 2, characterized in that, The clamp (42) consists of two connecting cylinders (421), with a cable test piece (43) between the two connecting cylinders (421). The ends of the two connecting cylinders (421) that are far apart from each other are threaded. A connecting hole (423) is opened at the center of the two connecting cylinders (421), and both ends of the cable test piece (43) are bonded to the inner wall of the connecting hole (423).

6. The deep-sea high-pressure multi-strain rate load testing device according to claim 2, characterized in that, The clamp (42) consists of a first connecting cylinder (424) and a second connecting cylinder (425). The first connecting cylinder (424) has a wire groove (4241) and a plurality of fixing rods (4242) on its inner wall. The second connecting cylinder (425) has a plurality of fixing holes (4251) that cooperate with the fixing rods (4242) on its inner wall.

7. The deep-sea high-pressure multi-strain rate load testing device according to claim 2, characterized in that, The clamp (42) consists of two connecting sleeves (426), and a cable test piece (43) is provided between the two connecting sleeves (426). The cable test piece (43) includes an outer sheath (431) and a battery core (432). A cone (4261) is provided inside each of the two connecting sleeves (426). A through hole (4262) for the battery core (432) to enter is opened at the axis of the cone (4261). The two ends of the battery core (432) pass through the cone (4261) respectively. The outer sheath (431) is in contact with the surface of the cone (4261). A hoop (4263) is provided inside each of the two connecting sleeves (426), and the hoop (4263) is fitted onto the end of the cable test piece (43).

8. An operating method applied to the deep-sea high-pressure multi-strain rate load testing device as described in claim 2, characterized in that, Includes the following steps: S1: Fix the vessel body (41) between the incident rod (26) and the transmission rod (44), and the clamp (42) fixes the cable specimen (43) to the end of the incident rod (26); S2: The deformation sensor (411) is directly clamped onto the cable specimen (43) through the pre-reserved hole on the vessel body (41) to measure the deformation of the specimen; S3: Use the water pump (54) to add water into the vessel (41) until water comes out of the vent hole on the vessel (41). Then the water in the vessel (41) is full, indicating that the gas has been vented. At this time, turn off the water pump (54). S4: Start the drive unit (52), set the pressure to the predetermined pressure value, and use the ball screw (53) to pressurize the vessel body (41). After the pressure is reached, the pressure sensor reads the pressure and the drive unit (52) drives the ball screw (53) to stabilize the pressure in real time. S5: Turn on the servo motor (21), adjust the low strain rate load loading device (2) to the predetermined static load value, and adjust the loading rate according to the different needs of creep and static tension; S6: Under the same pressure, different magnitudes of stress are measured by force sensors of different sizes depending on the object being clamped by the fixture (42).

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