At present, the pump construction method adopted by concrete pump truck is a single full-boom pumping method. During construction, the distance between the site of concrete application and the pump truck is very close, because the boom of the pump truck has a folding structure and can not be retracted as required by the crane boom. Therefore, construction work can only be all boom. The concrete that needs to be pumped must pass through the entire boom pipe to reach the point of use. In the concrete pump truck construction site often see the fact that: all construction started from the basic construction, in most cases, the concrete pumping height is limited, the distance is not large. Some construction projects from beginning to end belong to short, close pumping operation. However, in the existing pump full-arm pumping mode, only the boom can be fully deployed, so that concrete can be pumped through all the boom pipes. This kind of full-arm pumping mode inevitably brings a series of problems during construction: because of the long pumping pipeline, it is necessary to carry out high-pressure pumping, and the high pumping pressure causes the pumping system and pipeline to wear inevitably. At the same time the hydraulic system to work under high pressure conditions, but also brought the hydraulic system, high oil temperature, wear large parts; to carry out high-pressure pump, the vehicle engine must be high load, high speed operation, is bound to result in high fuel consumption, Large wear and tear parts, increased operating costs and reduce the life of the engine; Boom all unfolded concrete pumping operation, the pump center of gravity high stability, coupled with high pressure and high pressure pumping vibration, but also to the construction The safety poses a threat. During the construction of special environment, the boom may not be fully deployed due to the environmental conditions and will affect the pumping construction. In addition, the operation process of boom deployment and retraction needs to be carried out slowly, To a certain extent, the construction efficiency is also affected. In recent years, pump pumping distance record has been constantly refreshed, the maximum pumping height has reached 60 meters. Pumping more than 40 meters away from the pump truck has become the dominant model of concrete construction, these pumps in a lot of pumping a small distance of the basic construction, bridge construction of the above deficiencies, it is even more obvious. At present, concrete pump truck for short and near pumping construction operations, the whole boom pumping method, although it can achieve the purpose of pumping operations and the spectacular scene, but due to the limitations of mechanical structure, the function of the device can not get Reasonable application, can not be targeted to combine the construction environment and conditions to play a reasonable mechanical efficiency, resulting in a lot of waste in the process of using the pump truck. If the pump truck jib construction during pumping, according to the construction conditions and environment, choose to use the corresponding boom for construction, not only to solve the above problems, but also to obtain the corresponding positive effect. Can predict the market and customers on such products will be how to respond. Tianjin Binhai New Area Bo built concrete mixing station engineering and technical personnel, after the concrete pump truck construction site and operating conditions of the long-term observation and research, aiming at the shortcomings of the current concrete pump. The invention of a concrete pump truck (patent application number :) has been devised so as to allow the concrete pump truck to flexibly choose to use all jibs or partial jibs for construction work according to the size of construction work. The most prominent feature of the technical scheme of the present invention is that the pipe switch device and the auxiliary blowdown hose are installed on the boom of the pump truck, and the pumping pipeline can be conveniently and flexibly switched according to needs. That is to maintain the original technical performance of concrete pump truck, but also can be carried out in the short, short distance pumping construction, targeted to select part of the boom way for concrete pumping operation. When carrying out short and close pumping construction, the length of the pumping pipeline can be reduced by more than 25% compared with that of the original pump and the pump pumping height during horizontal pumping can be reduced by nearly 50%. "Partial boom" pumping mode as a supplement to the existing pump pumping mode, eliminating the existing shortcomings of the existing pump truck to improve the efficiency of the pump truck, concrete pump truck can give full play to the technical performance . The implementation of the technical scheme of the invention can make use of the partial boom or the whole of the concrete pump truck with the arm span of about 40 meters and especially the concrete pump truck of 40 meters or more in the arm span space range according to the distance or height of the pumping concrete, Boom for concrete pumping construction, so that concrete pumping construction more reasonable. In carrying out a large number of short, short distance concrete pumping construction, with the option to use part of the boom pump concrete pumping operation. Can effectively reduce the pumping pressure, reduce pipeline wear and tear, reduce the failure rate of mechanical parts, extend equipment life, improve work efficiency, save fuel and reduce emissions have considerable economic benefits and significant social benefits.