"Pumping capacity 72270 cubic meters; pumping time 1049 hours..." On May 18, Wu Dezhi, director of the concrete pumping Research Institute of Zhonglian Heavy Duty Section, in the monitoring room of Changsha, freely transferred the main technical parameters of a 56-meter high-precision and high-efficiency concrete pump truck being constructed in Changfeng County, Anhui Province.
On this day, this 4.0 edition of high-quality pump truck with craftsmanship spirit, high-precision and high-efficiency 56-meter concrete pump truck, won the first innovation award of Hunan Province, and became one of the 10 products that won this honor. Behind the achievements are the efforts and sweat of numerous scientific research experts and technicians.
"This is the result of our R&D team's struggle!" On the occasion of winning the prize, Wu Dezhi was deeply impressed by the scenes of fighting day and night.
In order to solve the problem of fatigue cracks in structural parts, Li Xiangan has been fighting continuously in a large experimental field full of dust and noise to carry out "fatigue experiments" on structural parts. In order to measure the vibration amplitude of the boom, Wanliang takes the experimental field as his home and stays for more than twenty hours.
To meet the needs of customers, Zoomlion launched a 4.0 product upgrading strategy in 2015. Zhonglian Zhongke Concrete Machinery Co., Ltd. locked in the 56-meter pump truck with the largest market coverage as a pilot product for upgrading. More than 10 core backbones of market, technology, manufacturing, technology, quality and service departments were selected to form a R&D team, focusing on pumping efficiency, fatigue life of structural parts, arm control, stability control of the whole machine. Energy saving and other aspects of technical research.
"Reliability of structural components is a key factor in determining the life of pump trucks." Wu Dezhi told reporters. Therefore, improving the service life of structural parts becomes the key to improve the quality of pump trucks.
In the past, the development path of pump trucks was that products were developed and manufactured, sold to customers, and then put into practice on the construction site. What problems should be returned to manufacturing enterprises by users after actual operation. Now, in order to solve the problem pertinently and prolong the service life of the product, the project team of Zhonglian Heavy Duty Branch has proposed a fatigue life simulation method of pump truck structural parts based on virtual prototype for boom and underframe support legs, which can predict the fatigue life of the structure at the design stage and judge the weak position of the fatigue life of the components. According to the classification of each weld, different quality grades of welds correspond to different fatigue stress thresholds to ensure that each weld has the required fatigue life. Then, the in-field equivalent test is carried out.
"Some places can not reach the expected life, from the beginning, redesign, manufacture and experiment; until the goal is achieved." Li Xiangan, the project team, told reporters that in winter of 2015, the test entered a critical period, which required more than three months to simulate the workload of pumping trucks for more than 10 years. Every day, the project team had to work uninterruptedly. Several people took turns on duty. "Everyone has to work 12 hours a day, often staying up until late at night. Cold, hungry and sleepy are the deepest memories of that time." Li Xiangan recalls.
Everything comes to him who waits. The results of field equivalent bench test show that the life of the boom and underframe leg of the 56-meter boom concrete pump truck, which has been optimized by fatigue design, has reached 450,000 square meters without cracking, and has reached the advanced level in Europe.
Wanliang also clearly remembers that in January 2016, the product entered the critical stage of ideal life experimental verification. At this time, the technology development team found that some key components of the product did not meet the ideal life expectancy. The Project Steering Committee assembled the relevant personnel overnight, from finding out the reasons to modifying the design drawings, to manufacturing, and then rotated continuously for two weeks, finally solved the related problems.
Nowadays, the high-precision and high-efficiency 56-metre concrete pump truck of Zhonglian Heavy Duty Branch has made breakthrough improvements in reliability, stability, maintainability, cost-effective fittings and remote upgrading of the system. The high-precision and high-pressure pumping system carried by Zhonglian Heavy Duty Branch is 5-8% higher than that of the industry, and its energy consumption is 2-4% lower than that of the industry. Active vibration reduction technology realizes the vibration control of the end of the boom under full working conditions within 200 mm to ensure the safety of construction. Full-condition adaptive pumping control technology focuses on breaking through the pumpability of poor materials, effectively overcomes the common problem of "picking food" in pumping system, and achieves a 65% reduction in the blockage rate of pumping. At present, there are 62 patents for this product, including 41 invention patents, 18 utility model patents and 3 design patents.
Numbers are abstract and customers feel most intuitively. As soon as the brand-new 56-metre pump truck was put on the market, it was sought after by the market. At present, the products have been sold to Anhui, Hubei, Shanghai, Guangdong, Jiangsu and northwest provinces and regions, with a total sales of 2.12 billion yuan, and the market share ranks first in the world in similar products.
