这个翻译好像有点牵强,符合泵的工作原理吗?这是整段英文。
The subsurface pump is essentially a plunger and valve arrangement within a tube or barrel. When the close-fitting plunger is lifted within the barrel, it creates a low-pressure region below the plunger, which is filled by fluid from the formation. Simultaneously, the plunger and rods lift fluid up the tubing. The valves are designed to open and close so that they allow fluids to enter the pump on the upstroke and be displaced above the traveling valve on the downstroke. The fluid above the traveling valve moves one full stroke upward on the upstroke.