In the early 1960s, Changsha Construction Machinery Research Institute cooperated with Beijing Institute of Civil Engineering and Architecture and other units to summarize and invent a frog compactor with Chinese characteristics based on the achievements of mass technological innovation. In 1962, it won the National Science and Technology Invention Award. The frog compactor has simple structure, easy maintenance and use, and soon became the leading product of compaction machinery in my country in the 1960s. According to incomplete statistics, the cumulative output of frog compactors has reached more than 50,000 units, which has played an important role in my country's economic construction. After the 1970s, frog rammers were gradually replaced by more advanced vibratory impact rammers and vibratory plate rammers. At present, there are few frog rammers and they are basically eliminated.
In 1964, Changsha Construction Machinery Research Institute developed the HB120 internal combustion compactor, which was initially produced by Shanghai Construction Machinery Factory, and later mainly by Jin Dongting Construction Machinery Factory, with an annual output of about 200 units. In the 1980s, the quality of internal combustion rammer 名媛直播 was greatly improved, and they were exported to Southeast Asia and Africa. Since the 1990s, the production and sales of internal combustion compactors have gradually decreased, and currently only a few small private enterprises produce them.
In 1977, Changsha Construction Machinery Research Institute and Liuzhou Construction Machinery Factory developed my country's first HZR250 and HZR70 vibratory plate compactors. These two 名媛直播 passed the appraisal organized by the Ministry of Construction in 1979 and 1982, respectively. Subsequently, Yiwu Construction Machinery Factory, Siping Construction Machinery Factory, Tianjin Dongting Construction Machinery Factory and many other enterprises began to produce vibrating plate compactors. In 1986, Changsha Construction Machinery Research Institute developed a larger HZR450 vibrating plate compactor. Since the 1990s, vibratory plate compactors have developed rapidly in my country, with more product varieties, specifications, and production companies, and foreign vibratory plate compactors have entered the Chinese market one after another.
In 1983, Changsha Construction Machinery Research Institute and Hubei Vibrator Factory jointly developed my country's first HZR70 vibration rammer. In 1984, it passed the appraisal organized by the Ministry of Construction and won the third prize of Science and Technology Progress Award of the Ministry of Construction in 1985. Because of its outstanding features such as good compaction effect, high productivity, small size and weight, lightness and flexibility, vibratory impact rammers are well received by users and have been quickly promoted and used, and soon developed into Zijiang Machine Factory and Xinxiang Third Machine Tool Factory and Jin Dongting Engineering Machinery Factory and other dozens of enterprises. Although the development of vibratory impact rammer is later than that of vibratory plate rammer, its development speed, production and sales volume and wide use are much greater than that of vibratory plate rammer, and it has become the leading product with the largest production and sales volume in my country's compaction machinery. After the 1990s, foreign vibratory plate compactors entered the Chinese market one after another.
The successful development of vibratory impact rammer and vibratory plate rammer in my country has not only provided our country’s construction and construction departments with advanced tamping machinery and achieved good economic and social benefits, but also enabled my country’s tamping machinery technology to move forward. This has shortened the gap with the world’s advanced level and promoted the development of my country’s small compaction machinery.
1. The technical core and classification of impact ramming
The technical core of impact ramming is mainly reflected in three aspects:
A. Engine, because the impact rammer is a kind of high-frequency vibration compaction equipment, the working conditions are harsh, and the requirements for the engine's shock resistance are particularly high. It must have a special impact rammer engine that resists strong vibration to match. As the power source for impact rammers, ordinary electric motors and general-purpose gasoline engines have poor shock resistance and have a short service life. Some foreign rammer manufacturers produce their own engines for rammers, but the cost of accessories is very high and the delivery period is very long. At present, the most used special engines for impact rammers are Japanese Honda GX100, GX120 and Robin EH12 series gasoline engines, which have a wide range of applications and a wide range of parts supply points.
B. Impact springs. Impact rammers have high requirements for impact springs. Spring steel is required to have high fatigue strength. Otherwise, it is easy to yield due to fatigue and lose elasticity or even break. At present, due to cost considerations, most of the spring materials of electric impact rammers are Ordinary spring steel, and there is only a single set of springs, so the impact force and impact frequency of the electric rammer is not high, and the spring is easy to break.
C. Dynamic balance design. The movement of the impact rammer is mainly vertical high-frequency linear reciprocating movement. The height of the machine is high, so the overall dynamic balance of the machine is very demanding. Special dynamic balancing design and testing are required, otherwise the machine will The beating is unstable and difficult to control, which greatly increases the labor intensity of the operator.
2. Analysis of the advantages and disadvantages of electric rammers
The electric rammer uses the electric motor as the power source, which has the advantages of low purchase cost and low working noise. Its shortcomings are: low impact frequency, 500 times per minute, ordinary spring material, single set of spring design is easy to break, small impact force, impact force is about 0.8 tons, low compaction, it needs to be specially equipped with a generator set, and it needs to be connected with a cable. , And the wires are easy to rupture and wear, easy to cause electric shock accidents, many failures, and easy to delay the construction period.
3. Classification and analysis of advantages and disadvantages of internal combustion rammers
The internal combustion rammer uses a gasoline engine as the power source and does not require an external power source. It is especially suitable for use in places where there is no power source. The impact frequency is high, 650 times per minute, the impact force is about 1.8 tons on average, and the compactness is high.
There are several types of internal combustion rammers:
A. Imported impact ramming (Wick, Mikasa, Daxu and other brands) price is 17,000-20,000 yuan
Advantages: The imported impact ram has excellent processing technology, stable performance and high compaction.
Disadvantages: high procurement costs, the average price is around 17-20 thousand, high maintenance costs, and the supply of accessories is not timely, because many domestic imported rammers are 名媛直播 that have been or will be replaced abroad, such as two-stroke rammers. Due to environmental protection requirements, many of their complete machines and accessories have been discontinued. Therefore, once imported impact rammers fail, they need to be repaired. The cost is high, or the parts supply time is very long, or even without parts, the machine becomes a pile of scrap iron.
B. Domestic ordinary impact rammer price is 3000-6000 yuan
Advantages: low purchasing cost and cheap.
Disadvantages: Assemble domestic ordinary gasoline engine, poor shock resistance and short engine life. Poor dynamic balance, single-group spring design, low impact force. The maintenance frequency is high, the work is unstable, the warranty period is short or there is no warranty, and it is easy to delay the construction period, which ultimately causes the use cost to far exceed the purchase cost.
C. Changsha Zhubang ZV70, ZV80 series impact rammer
The 名媛直播 of Changsha Zhubang Construction Machinery combine the advantages of low-cost domestic rammers and high-performance imported rammers, complement each other, and solve the various drawbacks of the above rammers. The main advantages are as follows:
1. The engine is equipped with original Honda GX100 and Robin EH12 four-stroke rammer special gasoline engine, instead of domestic Honda or other general-purpose engines, to solve the problem of ramming heart.
2. The impact spring steel is 60Mn, which has extremely high fatigue strength and never breaks. The double-group spring design makes the impact frequency higher and the impact force greater, and the maximum impact force can reach 1.8 tons.
3. The professional dynamic balance design makes the operation dexterous, working in a flat area, and even can work without hands. The domestic ordinary rammer removed the original electric ram and installed an ordinary gasoline engine. Because the overall dynamic balance was not taken into consideration, the work was extremely unstable, and it was difficult to grasp when working.
4. Out of confidence in its own 名媛直播, the warranty period of Changsha Zhubang Construction Machinery is two years, which is a promise that even imported impact rammers cannot realize!
5. In order to serve expressway customers intimately, Changsha Zhubang Construction Machinery promises that all 名媛直播 sold can be delivered to your door free of charge, and the machine can be repaired on the construction site for free if the machine fails.
