【Scientific and Technological Achievements' Introduction】 Rotating Parts Fault Monitoring System

my country's automobile industry has made rapid progress, and some products have reached or approached the international advanced level, but there are still a considerable number of automobile gears and gearbox products in terms of vibration, noise and fatigue life, which are significantly different from the international advanced level.

With the development of electric, lightweight and intelligent automobile industry, higher requirements are put forward for the design, production, processing and manufacturing of automobiles, so testing is indispensable in the process of automobile R & D and manufacturing.

Test object-car engine test object-car gearbox test object-car chassis axle

Xiao Bian today to introduce to you isThe fault monitoring system for rotating parts developed by the Institute of Test Equipment and Technology ("Test Equipment Institute") of our hospital.. The fault monitoring system of rotating parts is based on the structural vibration signal of the tested parts, mainly adopts the real-time online order analysis method, realizes the self-learning to generate the limit value, and can provide timely and effective alarm when the fault occurs. Let's understand this together.Breaking foreign technology monopolyThe product ~

 

science and technology research and development]

With the improvement of user requirements in the market and the stricter and stricter relevant laws and policies, higher and higher requirements are put forward for automobile R & D, production and manufacturing, especially for the efficiency of automobile engines, gearboxes, axles and other powertrain transmission systems., Economy, durability and other requirements are more stringent. In order to meet the above requirements, it is necessary to continuously optimize the product design and materials, find the optimal implementation scheme, and strictly control the production and manufacturing process and management. In this process, there will be a large number of parts that do not meet the design requirements and failure problems, so it is necessary to carry out a large number of tests on the parts in addition to simulation in the design process, record all the test data, provide timely and effective failure alarms, and strictly verify the design. In the production and manufacturing process, real-time online detection of products is carried out to eliminate unqualified products and avoid the outflow of problem parts. However, the regular subjective judgment by personnel experience and the alarm mechanism of the test bench itself obviously cannot meet the demand.

First of all, we will briefly introduce some basic concepts.

Q: What is a structural vibration signal?

A: We know that when the engine, gearbox, axle and other parts rotate, they will vibrate due to excitation. When the vibration is transmitted through the shell radiation and the air, we hear noise; and in the engine, gearbox, axle There is also vibration inside other parts, which is transmitted in the structure of gears, shafts, bearings and objects. This is structural vibration.

Q: What is order analysis?

A: We know that frequency refers to the number of times something happens per unit of time. The unit is usually expressed in Hz. The order, on the other hand, refers to the number of times that something occurs per unit cycle (turn, reciprocating cycle), which is related to frequency as follows:

where f is the frequency, r is the speed (rpm), and n is the order.

For example: one rotation of the shaft produces a vibration, and its order is 1; if there is a 7-blade fan on this shaft, each blade of the fan is subjected to air resistance after one rotation of the shaft, and the order of the fan It is 7 steps; 4 cylinders of a cylinder 4-stroke engine burn every two revolutions, so the combustion order of a 4-cylinder 4-stroke engine is 2 steps.

Based on the core testing technology, the Test Equipment Institute has continued to carry out a lot of research work based on research to solve the early detection problems of gear and gearbox products in terms of vibration noise, fatigue life, early failure monitoring, etc. At present, the rotating parts fault monitoring system products developed by the team can achieve accurate alarm of early faults.

The fault monitoring system for rotating parts can be used as a supporting product of the test bench, so let's learn more about what a test bench is!

The test bench for transmission components such as automobile gearboxes and engines is mainly used for design test verification in the product development stage, as a design aid to revise the design in time to seek the optimal design.

Rotating parts fault monitoring system is an important part of automotive testing. The electrification of automobiles makes the electric motor gradually replace the internal combustion engine as the new power source, and the electrification is developing in the direction of high speed. The high speed of the motor and the lightweight of the automobile will put forward a series of higher requirements for the design, production, processing and manufacturing of the automobile. For example, the requirements for the dynamic balance accuracy of high-speed shafts are getting higher and higher; resonance problems caused by system modal problems caused by high-speed and light-weight; and greater challenges to the life of gears and bearings at high speeds. Therefore, it is of great significance to develop real-time online test and diagnosis equipment to meet the requirements of testing work in the process of automobile R & D and manufacturing.

science and technology innovation]

Based on the order spectrum and power spectrum analysis of vibration signal, the product realizes the operation state monitoring and early fault diagnosis of the gear shaft system. Through the vibration signal monitoring and acquisition, the existing algorithm is improved and the optimal algorithm is introduced to analyze the order and power spectrum, and the position of the problem is inferred by calculation, so as to realize the accurate positioning and cause analysis of the early fault.

Let's explore the powerful functions and advantages of the product together ~

01 System Function Structure

Key features include:Real-time order analysis; power spectrum analysis; envelope demodulation analysis; speed frequency spectrum analysis; vibration index self-learning; vibration change and trend analysis; vibration alarm output; model analysis guidance; model data indicator storage; test data storage playback; modal analysis test.

02 Product Configuration

　Display:15.6“ 1080P Full HD；

　　CPU：Intel i5 6300U 2.4GHz；

　　RAM：8GB DDR3-1600；

　Hard Drive:500G；

Sampling rate:AIO overall 200KHz;

DIO single channel 40MHz.

03 Product Features

Monitoring standards:The product adopts the vibration signal (RMS) and vibration order spectrum energy index as the evaluation standard, and the trend spectrum analysis has provided the shutdown alarm standard.

Standard learning:By using several samples for standard self-learning, you can also click the "learn" button to correct the standard at the same time. The standard uses the Lada criterion, which is 3 times the standard deviation.

Means of analysis:

Order spectral envelope analysis-identify problems and locate the cause of the problem

Intensity chart (waterfall chart)-determine the severity of the problem at a macro level

04 Product Advantages

At present, many foreign companies have developed related products with a single positioning, either only for early failure and offline detection, or only for modal analysis. We developed this system is a feature-rich, highly integrated, highly modular real-time online monitoring system. Products have the following advantages::

1. Portable design, easy to carry;

2. The configuration is convenient and flexible, supporting multiple application scenarios;

3, high analysis accuracy, a professional fault analysis database, can accurately identify the fault;

4. Powerful function, able to support engine, gearbox, axle, motor and three-in-one powertrain.

 

application value]

At present, in the field of mechanical transmission, the early detection of gear shaft system fault can effectively prevent the problems caused by the defects of the transmission mechanism, and play an important role in optimizing the system performance and prolonging the service life. At the same time, on the basis of the continuous improvement of strong power in the automotive industry, the continuous lightweight of vehicles, the introduction of new energy power, and the ever-changing electronic design make automotive R & D institutions face a new round of challenges. In the future, especially in the powertrain (engine, gearbox, axle and drive wheels), car manufacturers will have to face market demand and adopt new materials and manufacturing processes. The newly designed product must be repeatedly tested in the development stage to ensure that the performance of the product meets expectations, and the early detection of faults can avoid damage to the prototype, effectively shorten the test time and cost of engine, gearbox and vehicle research and development, and bring strong impetus to the rapid development of the automotive industry.

Data on production inputs and outputs for the automotive test and diagnostic equipment market are forecast as follows:

At present, the early fault detection technology of tooth shaft system is in the hands of several foreign enterprises and is not open to the outside world. At present, there is less research on this aspect in China, and it is urgent to break the monopoly of foreign technology. At present, the field of new energy vehicles and high-speed transmission is developing rapidly, and automobile enterprises and research institutions have a huge demand for early fault diagnosis and monitoring. Therefore, our advanced technology and high-quality products and services will provide you with stronger market competitiveness.

 

Institute of Test Equipment and Technology

The Test Equipment Institute is a scientific research institution under the High-end Institute of Tsinghua Tianjin. It is mainly engaged in advanced test technology research, test equipment research and development, external test services (cooperation) and external engineering consulting services based on gear transmission systems. The Test Equipment Institute has gathered technical personnel from various disciplines such as machinery and electricity, making full use of the platform advantages of Tsinghua Tianjin High-end Institute and the technical advantages of previous technical teams. It has undertaken major projects in a short period of time and accumulated rich project experience, especially The project experience of the high-precision reducer test bench.

 

Technical docking and business negotiation

Contact: Zhu Huijuan

Mobile Phone: 13662143140

E-mail: zhuhj@tsinghua-tj.org

 

Source | Institute of Test Equipment and Technology

Editor | Wang Xiao

The final interpretation of the above related technologies belongs to the Institute of Test Equipment and Technology.