According to the special technical requirements of wind power towers, through targeted technical research and development, the technical scheme and typical structure of the plate rolling machine have been optimized and innovated to meet the industry’s requirements for equipment accuracy, efficiency, and safety. The promotion of this product has achieved significant social benefits. and economic benefits.
Foreword
The development of wind power is of great significance to improving the energy structure, protecting the ecological environment, ensuring energy security and achieving sustainable economic development.
The tower is an important basic load-bearing part of wind power equipment, and its processing and manufacturing are extremely difficult. The part is round and needs to be rolled by a 3 roll plate rolling machine. A single wind turbine requires more than 30 sections of the cylinder, so the steel plate rolling machine has a large workload. Improving the rolling efficiency is of great significance to the wind power equipment manufacturing progress and cost reduction.
Tower manufacturing requires one-time rolling and forming. Some steel plate rolling machine companies in China have developed a series of multi-specification wind power steel plate rolling machines with independent intellectual property rights, and have successively developed special plate rolling machines for wind power with a plate thickness of 100~220mm. , passed the acceptance test, the performance of the product met the design and wind power customer requirements, and was successfully delivered to the wind power enterprise.
Wind power tower technical parameters and accuracy requirements
Tower Technical Parameters
| Material | Low alloy structural steel, the yield strength is greater than 345MPa |
| Plate thickness /mm | 50~220 |
| Maximum diameter /mm | 4000~12000 |
| Maximum plate width /mm | 3500 |
| Overall maximum height/mm | 103000 |
| Cylinder weight/t | 1750 |
Tower Accuracy Requirements
| Allowable roundness of arc template /mm | ≤1 |
| Butt gap /mm | 0~2 |
| Allowable misalignment of longitudinal weld /mm | 0~1 |
| Allowable cross-section misalignment/mm | 0~1.5 |
Five technical research and innovation of wind power plate rolling machine
Conventional steel plate rolling machines cannot effectively meet the needs of the wind power industry. The main reasons are as follows:
- Insufficient main drive power
- Cylinder subsidence caused by large cylinder diameter
- cylinder wrong side problem
- The barrel needs to be welded
- The length of the plate is large, and it is difficult to roll and load the material
Insufficient main drive power
The rolling completion time of ordinary steel plate rolling machine is generally 3 to 5 times of pressing and rolling (about 1 hour for a single workpiece), and the rolling of wind power tower requires 1 time of pressing and rolling (about 15 minutes for a single workpiece). High rolling efficiency is required, and the main drive of ordinary plate rolling machines cannot provide power, and it is impossible to complete rolling forming at one time.
Improvement measures: increase the power of the main drive. Through the design calculation, the wind power plate rolling machine with a thickness of 180mm and a width of 3m needs a power of 300kW, while the main transmission power of the ordinary steel plate rolling machine is 150kW. It can be seen that to meet the requirements, the main transmission torque must be doubled to meet the one-time requirement after loading. Rolling cylinder requirements.
Cylinder subsidence caused by large cylinder diameter
Four reasons
The diameter of the wind power tower steel plate rolling machine is more than 8m, and its own weight is more than 30 tons. There will be different sags during rolling, and it is difficult to form;
During the plate rolling process, crane and other spreaders are needed to assist, and the auxiliary time is long;
There are potential safety hazards for personal equipment.
Improvement measures: Set up upper support and side support to solve the problem of cylinder sinking. The upper support is installed on the upper end of the upper working roll of the steel plate rolling machine. The upper support movable bracket can move up and down according to the needs to support the upper end of the cylinder to avoid self-weight and deformation and subsidence; the side supports are installed on the front and rear sides of the machine, which can swing up and down. When holding the lower end of the cylinder, the cylinder maintains a good roundness
Cylinder wrong side problem
During the rolling process, there are different degrees of radial and axial misalignment at the joint of the cylinder. The traditional solution is to use auxiliary tools or welding process blocks to force the two-way joint to be manually operated. For steel plates with a thickness of more than 100mm, the process is quite difficult and labor-intensive.
Improvement measures: set deviation correction device. The deviation correction device is installed on the side support, which can clamp the workpiece, and under the cooperation of the upper support and the side support, align the interfaces at both ends of the workpiece to achieve deviation correction.
The barrel needs to be welded
After rolling and forming, it needs to be welded at the seam. Ordinary steel plate rolling machines generally move the workpiece out or manually enter the cylinder for spot welding, resulting in increased auxiliary time, increased labor intensity of the operator, increased safety hazards, and unstable welding quality.
Improvement measures: set welding manipulator. The welding manipulator is installed on one side of the frame, and is driven by a servo motor to move forward, backward or swing, and weld the seam after the rolling is completed.
The length of the plate is large, and it is difficult to roll and load the material
The length of the board is 20000mm~30000mm, the hoisting and transportation of the board is inconvenient, the auxiliary material alignment takes a long time, and the safety is poor.
Improvement measures: feeding roller table and centering device. The feeding roller table has multiple butt joint lengths up to 30m, and the centering devices are arranged on both sides of the feeding roller table. It can realize motorized feeding and centering, which ensures safe and reliable work and reduces auxiliary time.
Improvement of CNC system for wind power plate rolling machine
The control system adopts a man-machine interface to dynamically monitor various actions and makes the position accuracy and synchronization accuracy more precise and the movement faster through PLC and various sensors.
Summary
Through innovation, the wind power plate rolling machine is already a comprehensive performance equipment. The change in the rolling process makes the structure of the wind power coiling machine have six characteristics:
- The main transmission power of the steel plate rolling machine is more than twice that of the ordinary plate rolling machine, which can meet the one-time rolling of the cylinder after feeding;
- The upper support and side support are set on the upper end of the steel plate rolling machine to support the large-diameter roll without sinking and ensure the roundness of the cylinder;
- Set up a deviation correction device, which is convenient for material matching and closing under the cooperation of the upper support and the lower support;
- Set automatic manipulator spot welding;
- Set the feeding roller table and centering device;
- Electrical and hydraulic system controls are precise and fast.
Through targeted technical research and development, the wind power steel plate rolling machine fully meets the user’s precision, efficiency, and safety requirements, and the promotion of this product has achieved significant social and economic benefits.
The development direction of wind power rolling machine
- Large-scale
Wind power generation technology is very mature, and large-scale (greater than 10MW) wind power technology is being developed. With the development of technology, the tower of wind power equipment will also be enlarged. The demand for machines is developing in the direction of large-scale. - Packaged
The current forming process is independently completed by a single machine and a single process, and the production efficiency is low. Optimize the structural performance and interface of the existing equipment, and gradually realize the automatic coordination and automatic operation of each machine. The control and structure of wind power plate rolling machine should be developed in the form of a wind power tower production line. - Intelligent
At present, the biggest bottleneck in the intelligentization of wind power steel plate rolling machines is the inability to quickly and accurately measure online, which is also a key technology that the same industry at home and abroad wants to overcome. In the future, we will focus on tracking cutting-edge technologies, research and develop intelligent detection, and gradually realize the intelligent control of the equipment. With the continuous improvement of information transmission and hardware control, intelligent logistics system delivery, big data network connection, and remote control, unmanned factories will gradually be realized.
Works Cited: Research and application of steel plate rolling machine in wind power industry – YANG Shutian, KONG Qingping, LI Yuhua, ZHANG Meilan, GAO Ronghua