我团建场以来,人工开挖了大量排水沟渠,这些沟渠两侧形成四、五米宽的壕棱子,占去可耕地面积竟达四万亩。因此,为了充分利用土地,必须尽快铲平壤棱子。但这些壕棱子起伏不平,杂草丛生,作业条件恶劣。另外,我团还迫切需要开挖上口宽十米、深三米左右的大型排水渠。开大型沟渠时,地表草垡成片,中层土壤湿粘,下层往往见水。为了在这种恶劣条件下,进行开大沟、铲壕棱的机械作业,我们从一九七四年五月开始研究试制前置式铲抛机。经过一年实践,一次大改进,于一九七五年四月试制出第一台PS—2.0铲抛机(图1)。截至一九七五年十月,该机已开渠、平地五万七千余方土。初步试验表明, Since the establishment of the regiment, a large number of drainage ditches have been excavated by hand, and four or five meters wide ditches on both sides of these ditches have taken up 40,000 mu of arable land. Therefore, in order to make full use of the land, Pyracantha must be shoveld as soon as possible. However, these ditches ripples undulating, overgrown, poor working conditions. In addition, my delegation also urgently needs to excavate the large-scale drains that are about 10 meters wide and about 3 meters deep. Open a large trench, the surface straw into a film, the middle layer of soil wet sticky, the lower often see the water. In order to carry out the mechanical operations of opening ditches and mooring edges under such harsh conditions, we started to study the trial-manufacture front-mounted shoveling machine in May 1974. After a year of practice, a big improvement was made and the first PS-2.0 shoveling and polishing machine trial was produced in April 1975 (Figure 1). As of October 1975, the aircraft has been opened to cover an area of ​​over 57,000 square feet. Preliminary tests show that,