Instead of the fixed horsehead, a rotary horsehead is adopted, which is hinged with one end of the added fiont pitman and can realize seir rotation with the motion of the walking beam.

• 主要改造内容是将固定式驴头改为旋转驴头，后者通过与增设的前连杆一端的铰接，可在游梁运动的同时实现自转。驴头公转和自转的冲程迭加，便达到增加冲程的目的。同时增添了曲柄副平衡块，以提高平衡扭矩。