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E-mail
qingjiyiqi@zhongguoqingji.com
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Phone
13402079333
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Address
208 Andong Road, Wuqiao Town, Fengxian District, Shanghai
Shanghai Qingji Instrument Technology Co., Ltd
qingjiyiqi@zhongguoqingji.com
13402079333
208 Andong Road, Wuqiao Town, Fengxian District, Shanghai
The core of the structural design of the high-temperature creep endurance strength testing machine revolves aroundThe three core requirements of "long-term high temperature stability, precise and constant load, and precise deformation monitoring" are composed of seven modules: main frame, loading system, high temperature furnace system, deformation measurement system, control system, safety protection system, and auxiliary system. Each module works together to ensure high stability and high testing accuracy in high temperature (room temperature~1600 ℃+) and long cycle (0~100000h) testing. The following is a detailed breakdown of the structure of each module:
1、 Host framework: high rigidity load-bearing foundation (core requirements: no deformation, anti vibration)
The host framework is the entire device's The 'skeleton' needs to withstand long-term constant loads (0.1kN~1000kN) and thermal radiation from high-temperature furnaces, ensuring no mechanical deformation during the loading process and guaranteeing load accuracy.
| core component | Material and structural design | function and role |
| Fixed crossbeam | High strength cast steel/Steel plate welding (with aging treatment to eliminate internal stress) | Fixed loading system, high-temperature furnace bottom support, providing stable load-bearing reference |
| Moving crossbeam | Made of the same fixed crossbeam material, it slides and matches with the column | Move up and down with the loading system, apply tension/Pressure load, the clearance between the crossbeam and the column should be ≤ 0.02mm to ensure coaxiality |
| column | 4 high-strength alloy steel structures (surface chrome plated for rust prevention), paired with precision ball screws | Connect the upper and lower crossbeams to ensure smooth movement of the crossbeam, while providing ultra-high rigidity (deformation of the column during loading)≤0.01mm/m） |
| base | Heavy duty cast steel base (weight)≥ 1/3 of the total weight of the equipment), with leveling feet | Fixed equipment as a whole, absorbs vibrations, and ensures the levelness of the host through leveling feet (levelness)≤0.1mm/m）， Avoid tilting and causing additional bending moments |
2、 Loading system: precise and constant load output (core requirement: long-term stability)≤±0.3% FS）
The loading system is responsible for applying a constant tensile force to the specimen/Pressure load can be divided into "electro-hydraulic servo type", "weight type", "spring type" according to the loading method, and the mainstream is electro-hydraulic servo type. The structure is as follows:
| core component | Material and structural design | function and role |
| Loading execution mechanism | Electro hydraulic servo cylinder (medium and large models)/Precision screw lift (small model) | The electro-hydraulic servo cylinder drives the piston movement through high-pressure oil to achieve tension/Pressure loading; The screw lift is driven by a servo motor and is suitable for small load testing |
| load cell | Column style/Ring type high-precision tensile sensor (material: alloy steel/stainless steel, accuracy level 0.1) | Real time collection of load signals, feedback to the controller to form closed-loop control, with a load measurement range of full range0.5%~100%, long-term stability ≤ ± 0.3% FS |
| Load transfer mechanism | High strength pull rod, universal joint joint | The pull rod adopts40CrNiMo alloy material (tensile strength ≥ 1000MPa), universal joint compensation specimen installation eccentricity to avoid additional bending moment affecting the test |
| Assist in loading components | Weight group (optional, used for calibration)/Pure static load test), buffer | The weight group achieves pure static loading through mechanical structure superposition, with minimal load drift (suitable for ultra long term testing); Buffer absorbs the impact of loading moment to avoid load overshoot |
3、 High temperature furnace system: uniform and stable high temperature environment (core requirement: temperature control accuracy) ± 1 ℃, temperature field uniformity ≤± 3 ℃)
The high-temperature furnace system is the core of simulating the high-temperature service environment of materials, which needs to achieve long-term high-temperature stability and uniform temperature field. The structural design focuses on Heating uniformity, insulation, and temperature resistance:
| core component | Material and structural design | function and role |
| Furnace shell | Cold rolled steel plate spray coating (outer layer)+Insulation layer (middle layer)+inner liner (inner layer) | The shell is protected against moisture, the insulation layer reduces heat loss, and the inner liner provides a high-temperature chamber |
| insulation layer | High density ceramic fiber (thermal conductivity)≤ 0.03W/(m · K)+alumina insulation brick | Multi layer insulation design, furnace shell surface temperature≤ 60 ℃ (at a test temperature of 1200 ℃), to avoid heat leakage and scalding of operators |
| heating element | Select by temperature range:-Medium temperature (≤ 800 ℃): Nickel chromium alloy wire (temperature resistance 850 ℃) - High temperature (800~1200 ℃): Silicon carbon rod (temperature resistance 1400 ℃) - Ultra high temperature (>1200 ℃): Molybdenum wire/graphite rod (temperature resistance 1600~2000 ℃) | Uniformly distributed on both sides of the furnace cavity/Surrounding the area (such as 6-8 symmetrically arranged), heating is achieved in different zones through PID regulation to ensure uniform temperature field |
| Inner liner (furnace chamber) | Medium temperature:SUS304 stainless steel high/ultra-high temperature: alumina ceramic tube/graphite furnace liner | Corrosion and high temperature resistance, cylindrical furnace cavity shape (to avoid dead corners of airflow), inner diameter designed according to sample size (usually φ50~150mm） |
| Temperature measuring element | S-type/R-type thermocouple (temperature measurement range 0~1600 ℃, accuracy ± 0.5 ℃) | The thermocouple probe is fixed near the sample gauge section (distance from the sample)≤5mm）， Real time collection of sample area temperature and feedback to the controller |
| Atmosphere interface (optional) | Inlet (inert gas)/Protective gas), outlet, vacuum interface | Suitable for testing easily oxidizable materials, can be filled with argon gas/Nitrogen (purity ≥ 99.99%) or vacuum (≤ 10 ⁻ ³ Pa) to prevent high-temperature oxidation of the sample |
4、 Deformation measurement system: Accurately capture creep deformation (core requirement: resolution)≤0.0001mm）
The deformation measurement system is responsible for real-time monitoring of the creep deformation of the specimen at high temperatures (including initial creep, steady-state creep, and accelerated creep stages), and is the core for obtaining creep curves and key indicators. It is divided into Contact and non-contact:
| core component | Material and structural design | function and role |
| Contact type high-temperature extensometer | Temperature resistant material: ceramic/Inconel alloy (temperature resistance ≤ 1200 ℃) structure: double clamp type, adjustable gauge length (25-50mm), equipped with spring pre tensioning mechanism | Directly clamped at both ends of the sample gauge, through a differential transformer/The grating ruler converts mechanical deformation into electrical signals, with a deformation measurement accuracy of ≤± 0.001mm and a resolution of ≤ 0.0001mm |
| Non contact laser extensometer (optional) | Structure: Laser emission end+Receiving end (symmetrically arranged on both sides of the high-temperature furnace), monitored through a quartz observation window | Based on the principle of laser triangulation, non-contact measurement of deformation in the gauge length section of the sample is carried out to avoid impact damage caused by high-temperature oxidation and sample fracture, and is suitable for ultra-high temperatures（>1200 ℃) or easily oxidizable samples |
| displacement sensor | Grating ruler (resolution)≤0.001mm）， Installed between the moving crossbeam and the fixed crossbeam | Auxiliary measurement of beam displacement, used for calibrating extensometers or monitoring large deformations (such as total deformation after sample fracture) |
| Signal transmission module | High temperature shielded cable, signal amplifier | Shielding electromagnetic interference and thermal radiation from high-temperature furnaces, amplifying weak deformation signals, and ensuring stable data transmission |
5、 Control System: Equipment Operation and Data Processing Center (Core Requirements: Automation, High Reliability)
The control system belongs to the equipment The 'brain' is responsible for coordinating the work of various modules, achieving precise control of temperature and load, as well as data acquisition, processing, and report generation. The structure is as follows:
| core component | Material and structural design | function and role |
| Controller hardware | PLC+industrial computer (embedded/desktop)+touch screen operation | PLC is responsible for real-time control (temperature, load, deformation acquisition frequency ≥ 10Hz), industrial computers are responsible for data storage and analysis, and touch screens support parameter setting, real-time monitoring, and operation |
| Temperature control module | PID+fuzzy control algorithm, staged heating program | Control the power of heating elements to achieve The heating process of "rapid heating → slow approximation → constant temperature stability" has a temperature control accuracy of ≤± 1 ℃ to avoid temperature overshoot |
| Load control module | Electro hydraulic servo controller（Moog/Atos+closed-loop feedback regulation | Control the pressure of the servo cylinder or the speed of the screw motor to maintain the load stable at the set value Within ± 0.5%, supporting two control modes of constant stress/constant load |
| Data collection and storage module | High speed data acquisition card (sampling rate)≥100Hz）、 Hard disk/SD card storage | Automatically collect temperature, load, deformation, and time data, supporting continuous storage≥ 10000 hours of test data, with power-off recovery function (data is not lost after power failure, and automatic testing is resumed upon incoming call) |
| software system | Specialized testing software（Windows/Linux system) | Function:① Parameter settings (temperature, load, testing time, stopping conditions); ② Real time drawing of creep curve (ε - t curve); ③ Automatically calculate indicators such as creep strength, endurance strength, creep rate, etc; ④ Report generation and export (Excel/Word/PDF); ⑤ Remote monitoring (supports viewing test status through mobile/computer apps) |
6、 Security protection system: ensuring the safety of equipment and personnel (core requirement: high reliability)
Considering the particularity of high temperature, high pressure, and long-term testing, the safety protection system needs to cover Multiple dimensions such as high temperature protection, overload protection, fracture protection, and electrical protection:
| core component | Material and structural design | function and role |
| High temperature protective cover | Double layered tempered glass+Stainless steel frame (high temperature resistant, impact resistant), covering the outside of the high-temperature furnace | To prevent operators from being scalded by high temperature radiation, and to facilitate observation of the sample's condition, the glass surface is coated with an anti fog layer (to avoid high-temperature water vapor fogging) |
| Overload protection device | Mechanical limit switch+Electronic overload alarm (triggered when the load exceeds 110% of the full range) | Mechanical limit prevents excessive movement of the crossbeam, electronic overload automatically unloads and alarms, avoiding equipment and sample damage |
| Sample fracture protection | Deformation mutation detection algorithm+Emergency unloading valve | When the sample fractures, the deformation suddenly changes, and the controller quickly triggers the unloading command to stop loading and cool down, preventing the splashing of fracture fragments |
| Electrical protection | Leakage protection switch, overcurrent protection, grounding protection | Prevent electrical short circuits and leakage accidents, equipment grounding resistance≤4Ω |
| Other protections | Broken couple protection (automatic shutdown when thermocouple is disconnected), water cooling fault alarm (water cooling model), atmosphere pressure monitoring (atmosphere model) | Dealing with abnormal situations during the testing process to avoid equipment damage or test failure |
7、 Auxiliary system: ensuring long-term stable operation of equipment
The auxiliary system is a supplement to the normal operation of the equipment and can be optionally selected according to testing requirements. The core includes:
| core component | Material and structural design | function and role |
| cooling system | Water cooling unit (industrial chiller, cooling capacity)5-30kW)/air-cooled radiator | Cooling the high-temperature furnace shell, loading oil cylinder, fixtures and other components to avoid component failure caused by high temperature and maintain equipment operation stability |
| Atmosphere control system (optional) | Gas cylinders, pressure reducing valves, flow meters, gas purity filters | Inject inert gas (argon) into the high-temperature furnace/Nitrogen), flow rate adjustable (0~5L/min), ensuring oxygen content in the furnace ≤ 10ppm to prevent sample oxidation |
| Vacuum system (optional) | Rotary vane vacuum pump+Vacuum gauge (measuring range 10 ⁵~10 ⁻ ³ Pa) | Realize a vacuum environment inside the furnace, suitable for testing special materials that are sensitive to oxidation, such as titanium alloys and high-temperature ceramics |
| Sample fixture | High temperature resistant alloy fixture（Inconel/molybdenum alloy, temperature resistance ≥ 80% of test temperature), including wedge-shaped self-locking fixtures/threaded fixtures | Fix the sample firmly and ensure good coaxiality (deviation between the sample axis and the load axis)≤ 0.5 °) to avoid additional bending moments affecting the test |
Schematic diagram of overall structural layout (simplified)
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[Top: Moving crossbeam]
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[Loading System: Servo Cylinder/Screw Lift+Load Sensor]
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[High temperature furnace system: furnace body+heating element+thermocouple+atmosphere interface]
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[Sample fixture: upper fixture (connected to load sensor)+lower fixture (connected to fixed crossbeam)]
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[Deformation measurement system: extensometer (clamping sample gauge segment)+laser transmitter/receiver (both sides)]
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[Fixed crossbeam+column+base]
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[Control System: Operation Screen+Industrial Computer+Controller]
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[Auxiliary system: Water cooling unit+Atmosphere steel cylinder+Vacuum system]
[Safety protection: High temperature protective cover+overload protection+electrical protection]
Summary of Key Points in Core Structure Design
High rigidity: The host frame is made of heavy-duty cast steel and high-strength alloy to ensure long-term loading without deformation;
High temperature resistance: Components such as high-temperature furnaces, fixtures, and extensometers that come into direct contact with high temperatures are made of heat-resistant materials (ceramics, high-temperature alloys, molybdenum)/Graphite);
High stability: The loading system adopts closed-loop control, and the temperature control adoptsPID+fuzzy algorithm, high-precision sensors are used for deformation measurement to ensure stable long-term test data;
Safety: Protection design, covering risk points such as high temperature, overload, fracture, and electrical issues;
Scalability: Supports optional configurations such as atmosphere control, vacuum system, laser extensometer, etc., to adapt to different materials and testing needs.
This structural design ensures that the equipment can operate stably under testing conditions (high temperature, long cycle, high load), accurately obtain creep and durability performance data of materials, and provide reliable support for the design and life evaluation of high-temperature components.