D25型筒式柴油打桩锤及DJG25型多能桩架统称轨道式打桩机(见封面),是天津市搅拌机制造厂生产的。该打桩机原为建筑机械研究所与上海工程机械厂共同研制的,后由浦沅工程机械厂生产,现转产于天津市搅拌机制造厂。在生产过程中又进行了改进,尤其是D25型打桩锤改动比较大,已经将风冷改为水冷,加设了自动润滑装置,上汽缸也加长了,并采用了结构比较简单的移动轴式起落架和稀土镁球墨铸铁的活塞环等,使其工作性能有了改善。天津市搅拌机制造厂是按最新图纸进行试生产的,桩锤和桩架都进行了试验,均已达到了设计要求,并于1980年10月通过了转厂生产 D25 type diesel diesel pile hammer and DJG25 type multi-energy pile frame collectively referred to as orbital pile driver (see cover), is produced by the Tianjin mixer factory. The pile driver originally was jointly developed by the Institute of Construction Machinery and Shanghai Engineering Machinery Factory, and was later produced by the Puyuan Construction Machinery Plant. It is now being converted to a mixer factory in Tianjin. In the production process, improvements have been made, in particular, the D25 pile hammer has been greatly changed, the air cooling has been changed to water cooling, an automatic lubrication device has been added, the upper cylinder has also been lengthened, and a relatively simple structure of the moving shaft has been adopted. Landing gear and piston rings of rare-earth magnesium ductile iron have improved their performance. The mixer factory in Tianjin is in accordance with the latest drawings for trial production. The pile hammers and pile racks have all been tested. They have all met the design requirements and passed the conversion to production in October 1980.