| The concrete delivery pump has been one of the most widely used construction machinery and the farm machinery. It can once finish horizontal and vertical transportation in succession, with high efficiency, low workforce and expense. Especially in the construction sites that other transporters is difficult to close, concrete delivery pump can work effectively. Today the combination of the mixed concrete production and pump sending construting changes the appearance of construction site. The skill of pump moulding promises the high efficiency and good quality of the construction, which is more and more favored in construction field. Recently with the rapid progress of economic, the technique of concrete delivery pump has been developed remarkably. However, some key problems which exist in concrete delivery pump homemade, whatever closed hydraulic system or open hydraulic system, have not been solved and what's more, will become more severe with the increased requirement for concrete delivery pump in the course of modernization of our country. As is well known, the hydraulic system play an important role in concrete delivery pump, the correctness and rationality of the design for the hydraulic system has great impact on both the function of the concrete delivery pump and the reliability of whole concrete delivery pump. As far as the design of the closed hydraulic system, some problems need to be solved. For example, how to reach the harmony of pumping, swing and stir; how to realize swiching off the pressure of quickly exchanging pump and how to reduce automaticly main pump out caused by exterior load's changes in order to power matching and so on. As for the open hydraulic system, there exist several problems such as thermal balance and oil cleanness degree of the hydraulic system as well as hydraulic shock. All the problems mentioned above have been the bottlenecks which restrict the development of pump skill in our country severely. So in this paper we take all this problems as our main study object and investigate them in depth. Has obtained the important research results, has the certain theory and the practical significance. In the consult massive domestic and foreign literature data base, in detail elaborated the domestic and foreign concrete delivery pump development present situation and the tendency. Elaborated the concrete delivery pump closed type hydraulic system composition and its the principle, and in this foundation, take the HBT80 closed type concrete delivery pump as the example, to the closed type hydraulic system two important return routes -pumps over return route, swung the return route to carry on the detailed thorough analysis, has studied between two return routes close coordinated relations. Obtained two return routes to have to be this important conclusion which the synchronization carried on, in order to achieve this goal, swung the hydraulic cylinder to have to use the cushion structural design. Confirms after the experiment, the obtained conclusion is correct. Using "SN" the control technology, has solved the pressure impact and the host oil pump for the first time which the closed type hydraulic system host oil pump because outside carries causes attracts the spatial phenomenon. After the prototypical experiment, proved the plan was reasonable, causes the pressure impact to reduce 40%. Has the good application prospect. In order to solve the closed type concrete delivery pump pressure to shut off and the power match and so on the essential core technology, myself have designed the multi-purpose current capacity pressure control valve specially. This valve has the following function: 1, the adjustment zero opens the moving point, enables the engine to achieve above certain rotational speed when can have the pump over, guarantees when the engine idling regime does not have the operation misoperation; 2, the realization pressure shuts off the function, enable the host oil pump pivot angle to obtain a dynamical equilibrium, the system host safety valve does not open, the realization pressure shuts off; 3, the speed sensitive control may cause the motive machine to be at the maximum work rate condition, enhances the engine the use power. After the installing equipment experiment, proved designs is correct,moreover the use effect is good. The first time application power linkage chart theory has carried on the analysis to the HBT80 closed type concrete delivery pump pump over return route, and according to the above has established the pump over return route system dynamic system of equations. Has carried on the dynamic simulation using the MATLAB Simulink function to the system, obtains through the simulation: The concrete delivery pump "SN" the function may effectively eliminate the concrete delivery pump the pressure impact which instantaneous produces in the compaction concrete, thus has proven the theoretical analysis accuracy. After to the prototypical experiment, to the actual curve and the simulation curve which obtains carries on the comparison, two is tallies. Thus proved the modelling is correct. Opens the type concrete delivery pump hydraulic system thermal equilibrium to HBT60G the analysis, the computation, discovered has opened the type system oil temperature excessively high question to be at. Namely was using in a big way, the small cavity cut two six commutation valve port has had the very tremendous pressure loss, thus caused the system the calorific capacity to be very big. Through connects the cavity in the big cavity to establish lid typeface two to insert installs the valve, this valve has the following characteristic: 1, through combines the plug-in unit and the valve cover, may constitute the direction, the current capacity as well as the pressure and so on the many kinds of control function. 2, because the major part is the mushroom valve type structure, the interior divulges extremely slightly, does not have the deactivation phenomenon. Has the good responsiveness, can realize the high speed transformation. 3, most suits requests the high pressure, the great current capacity system which the small pressure loses. 4, inserts installs the valve to load directly the integrated block in the cavity, therefore reduced the oil leak, the vibration, the noise and matches the breakdown which the tube causes, enhanced the reliability. 5, because has realized the hydraulic unit compact integration, but large scale reduces the installment space and the area, compared with the convention hydraulic system reduced the cost. This place the improvement caused the pressure loss to reduce 50%. Meanwhile proposed to the hydraulic fluid tank the many kinds of improvementsdesign proposal, confirmed after the experiment, radiates the ability to enhance 30%. In order to adapt the ambient temperature change, the chiller choice, should the comprehensive utilization forced-air cooling type chiller and the water-cooled chiller merit. Namely under general temperature environment, use forced-air cooling type chiller, but increases under the superhigh temperature environment uses the water-cooled chiller. After to the prototypical experiment, the plan which designed is correct, had guaranteed the system oil temperature did not surpass 80 ℃. The present paper systematically introduced the fat liquor contamination control question, this question opens in the type hydraulic system in the concrete delivery pump to display the outstandingly. The research discovered that, The solid particle pollution is the fat liquor main source of pollution. In manufacture process primary device remaining wears in with the early time is the solid particle pollution main reason. The feasible key to the situation is the machine leaves the plant in the testing by special-purpose to filter the purifier to replace machine itself the fuel tank with to filter the system, like this guaranteed the machine leaves the plant when fat liquor clean degree and filter service life. Confirms the filter after the experiment the life to increase from 300 hours to 800 hours. Operates the type concrete delivery pump take HBT60G as the example, multianalysis in concrete delivery pump universal existence pressure impact question. And operated the type concrete delivery pump to HT60G the pump over return route with to swing the return route to propose the corresponding solution, passed through the corresponding actual experiment to prove these plans were feasible, caused the hydraulic pressure impact to reduce 50%. The present paper these key questions which existed in view of the domestically produced concrete delivery pump has conducted the correlation research. Realized the closed type hydraulic system pump over, swung between two return routes close coordinations, realized the pressure to shut off, between the power match organic synthesis. Improved has opened type aspect the and so on hydraulic system thermal equilibrium, pressure impact and fat liquor contamination control condition. The present paper does the research work regarding enhances the domesticallyproduced concrete delivery pump the technical level to have the certain theory significance and the project application value, also has the certain impetus function to the agriculture water conservancy facility.
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