Application of wireless temperature sensor on press
Bearing is an important part of modern mechanical equipment. Its main function is to support the mechanical rotating body, reduce the friction during its movement, and ensure its rotation accuracy. Not only that, the bearing will also affect the transmission accuracy. In order to ensure the normal function of the bearing in the mechanical equipment and ensure the safe and reliable operation of the equipment, the running state of the bearing must be monitored.
There are many factors that affect the normal operation of the bearing. For example, insufficient lubrication and poor installation accuracy may cause an abnormal increase in the temperature of the bearing. If the machine stops immediately, it can effectively avoid the occurrence of equipment, product quality and even personal safety accidents.
It can be seen that the monitoring of bearing temperature is of great practical significance for equipment maintenance, especially for heavy-duty and high-speed bearings, it is more necessary to install temperature sensors. This article will combine bearing temperature detection to introduce the successful application of a wireless temperature measurement technology on the press.
Background of the project
This wireless temperature measurement project is a retrofit project for bearing temperature monitoring on an old automobile press line. Since temperature monitoring equipment was not included in the original scope of supply, the main transmission system of the upper beam of the original press (Figure 1) was not considered on the equipment. Design structures such as slotting and wiring. In addition, the current equipment is in a normal production state and does not have long-term shutdown conditions. At this time, the wireless temperature sensor shows its unique application advantages in this specific situation due to its compact structure and free wiring.
Design Ideas of Wireless Temperature Measurement System
This system uses a decentralized temperature sensor installed on the spot to collect the temperature data of the measured point through direct contact with the temperature measurement location, and then the sensor uploads the collected temperature data signal to the wireless temperature measurement repeater in a wireless manner. The receiver then enhances the received signal and forwards it to the wireless temperature measurement host. The wireless temperature measurement host can display the temperature data of the measured point in real time. It also has the functions of saving historical data and alarming the temperature of the measured point. The topology of the system The figure is shown in Figure 2.
Figure 1 The internal main drive system of the upper beam of the press
Figure 2 Topology diagram of wireless temperature measurement system
Advantages of wireless temperature measurement system
Compared with the traditional wired temperature measurement method, the advantage of the wireless temperature measurement system is not only reflected in the “wireless” point, but also has other advantages.
⑴Because of the avoidance of wiring, the equipment itself has fewer slots and holes, which has a lower impact on the strength of the equipment itself, and the installation period is short, and the installation is convenient and flexible.
⑵Because of getting rid of the limitation of wiring, the layout of the wireless temperature sensor is more flexible and more compact than the traditional wired method.
⑶ The wireless temperature measurement method has flexible networking and stronger scalability.
Applicability analysis of project transformation
SMD wireless temperature sensor
This type of SMD wireless temperature sensor (Figure 3) adopts a low-power design and is powered by a 3.6V high-temperature resistant lithium battery without external power supply. It uses wireless communication to send the collected temperature data to the host. The data is sent every time the temperature changes. If there is no temperature change, the data is refreshed every 15 minutes, which extends the battery life. The sensor adopts a metal design as a whole to form an electromagnetic shield, which is not interfered by the surrounding magnetic field and can work stably in a strong electromagnetic field; it is easy to install and only needs two stainless steel screws to fix; the sensor adopts an anti-vibration structure, which fully meets the needs of the press shop.
Taking into account that the upper beam of the press is a closed structure, wireless communication technology is adopted to verify the signal transmission of the sensor. The maximum transmission power does not exceed 10mW, and the farthest transmission distance is not less than 300m. The detection temperature adopts a repeater to further the signal. After enhancement, it is converted to the wireless display host. The host communicates with the PLC system of the press. The abnormal temperature alarm is interlocked with the press operation to realize data visualization and interlock protection, so as to predict the risk, easy to find the source of the problem, and completely avoid abnormalities. Major damage and even damage to structural parts caused by temperature rise.
Motion interference check and strength analysis
Use 3D modeling technology to simulate the movement of the main transmission components to check whether the installation position interferes, as shown in Figure 4.
Using the finite element analysis software to check the strength of the installed perforated parts, the finite element analysis of the bearing housing shown in Figure 5 shows that the perforating has little effect on the strength of the bearing housing.
Figure 3 SMD wireless temperature sensor
Figure 5 The impact of drilling on the strength of the bearing seat
Figure 6 Schematic diagram of the wireless sensor mounting board
Figure 7 Physical display of wireless sensor installation
According to the installation environment and requirements of this wireless sensor, a mounting plate is designed and manufactured, as shown in Figure 6, to fix the sensor. At the same time, mounting holes are designed at both ends of the mounting plate, and stainless steel bolts are used to fix the sensor in the press beam. In the position, use high-strength thermal conductive glue to fill, taking into account the installation firmness and temperature measurement accuracy. The actual installation effect is shown in Figure 7.
Transformation and practice
Through the above-mentioned series of applicability studies on the signal penetration ability of the wireless temperature sensor and the intensity analysis of the motion interference, it can be known that the wireless temperature sensor can be better used in the press shop. At the same time, its installation flexibility and convenience perfectly match new and old models, which is of great significance to retrofit projects. Field practice shows that the wireless temperature measurement system is stable and accurate. Through the promotion and application of this kind of technology, equipment users and maintainers can realize real-time monitoring of key parts of equipment, effectively reducing the difficulty of equipment inspection, and having a multiplier effect on preventive maintenance of equipment.
In addition, with the development of communication technology and network technology, the current wireless temperature sensor manufacturer has launched a mobile APP, which can upload and download data through cloud platform technology. That is to say, equipment maintenance personnel can realize remote monitoring and diagnosis of equipment only through mobile phones without leaving the house, which greatly improves the convenience of operation and maintenance and the safety of equipment.
It is a bold and meaningful attempt to apply the wireless temperature sensor to the bearing temperature monitoring of the press. Through the popularization and application of new technologies, users and maintainers of equipment have undoubtedly added another weapon to protect equipment safety.