In addition, {HEAD ~ the present apparatus} comprises {TAIL ~ surface interfaces} between a slidable sleeve and a mandrel to minimize a probability of mandrel and sleeve separation during the plungers ascent phase and a risk of plunger stall 
comprises
In addition , { HEAD ~ the present apparatus } comprises { TAIL ~ surface interfaces } between a slidable sleeve and a mandrel to minimize a probability of mandrel and sleeve separation during the plungers ascent phase and a risk of plunger stall
OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH