Hydraulic crushing hammer is a crushing tool that converts hydraulic energy into mechanical impact energy. It belongs to the field of fluid transmission and control technology. It is widely used and has huge domestic and international markets. It has formed a modern high-tech industry. At present, my country's market can be divided into European (accounting for 1%), Japanese (accounting for 8%), Korean (accounting for 23%), domestic brands (accounting for 27%) and other assembled products (accounting for 41%) according to the composition of brand sales. Domestic brands have a low market share, and the hammer breaker industry is still in the development stage. Since the introduction of hydraulic breaking hammers in the 1970s, they have been developing slowly and without transformative progress. Aiming at the problems of complex structure, low efficiency, high noise, inability to regulate frequency and energy, and difficulty in measuring impact energy, this project is supported by the general project of the National Natural Science Foundation of China, the key scientific and technological research projects of the Shanghai City Science and Technology Commission and the scientific and technological research and innovation projects of the Shanghai City Education Commission. With the support of the project, industry-university-research has jointly tackled key problems, starting from key technologies such as intelligent control, high-frequency control, stroke feedback control and testing methods of the breaking hammer, and has carried out long-term research and practice, forming a number of original results.
The main original achievements include: 1) Intelligent control: The three technical principles of microcomputer control, nitrogen pressure feedback, two pairs of high-speed on-off valves matched with cartridge valves to control piston movement and microcomputer control, nitrogen pressure feedback, a pilot valve with a high-speed on-off valve as a reversing valve to control piston movement, and a digital oil cylinder to drive pulley set stroke to control piston movement, realize stepless frequency modulation and energy regulation or intelligent control of the hydraulic crushing hammer, increase the piston stroke several times and greatly improve the impact efficiency of the crushing hammer. 2) In terms of high-frequency control: For the first time, the technical principle of using a high-speed hydraulic motor to drive the eccentric gear set to rotate at high speed to generate alternating upper and lower exciting forces is proposed, which improves the construction efficiency by 3-5 times, saves fuel consumption by 30%, and the construction noise is only 50-75 decibels. By controlling the speed of the hydraulic motor and the amplitude of the eccentric block, the function of frequency modulation and energy regulation of the hydraulic breaker hammer can be achieved. 3) Stroke feedback control: There are three technical principles: the pilot valve that uses remote pressure regulating valve as the reversing valve stroke feedback controls piston movement, two cartridge valves direct stroke feedback controls piston movement, and the hollow slide valve direct stroke feedback controls piston movement. It realizes the driver's remote frequency modulation and energy regulation function, simplifies the structure of the breaking hammer, shortens the length of the oil passage, and reduces fuel consumption, thereby improving work efficiency. 4) In terms of testing technology: Two test methods, oscillograph and Simpson test methods, were used to overcome the technical problem of testing the impact energy of the breaker.
The results of this project have authorized 6 invention patents, applied for 3 invention patents, authorized 16 utility model patents, authorized 1 computer software copyright registration, formulated 1 Shanghai City enterprise standard, published 73 high-level papers (including 18 SCI and EI), published 6 related professional works, and trained 20 master's degree students.
According to the technical principles of this project, seven new hydraulic breaking hammers based on different working principles have been proposed, and six breaking hammer prototypes and breaking hammer comprehensive test bench prototypes, including intelligent, high-frequency, pilot-operated, cartridge valve type and hollow slide valve type, have been developed. Some of these technologies have been industrialized in Shanghai Shangming Machinery Technology Co., Ltd., and two products, SV series high-frequency breaking hammers and breaking hammer comprehensive test bench, have been developed, with a cumulative new output value of 28 million yuan in the past three years. Profits and taxes of 4.4 million yuan; High frequency breakers have been exported to Germany, Russia, Australia, India and Malaysia, earning US $1 million. The high frequency breakers sold have been matched with the excavators of users for engineering construction operations, creating indirect economic benefits of more than 1 billion yuan. Significant economic and social benefits have been achieved. The high-frequency hydraulic breaker hammer has passed the test of Shanghai City Quality Supervision and Inspection Technology Research Institute and EU CE certification, as well as domestic and foreign novelty searches at the Science and Technology Novelty Searching Workstation of the Ministry of Education. The level of results has reached the international advanced level, filling the domestic gap. The intelligent hydraulic breaker has passed the acceptance of the Shanghai City Science and Technology Commission, and its achievement level has reached the international advanced level. The pilot-operated hydraulic breaker has passed the acceptance of the Shanghai City Education Commission, and the level of results has reached the domestic advanced level.