the wellbore for a plug-and-perf job is generally composed of standard steel casing, cemented or uncemented, set in the drilled hole. once the drilling rig has been removed, a wireline truck is used to perforate near the bottom of the well, and then fracturing fluid is pumped. then the wireline truck sets a plug in the well to temporarily seal off that section so the next section of the wellbore can be treated. another stage is pumped, and the process is repeated along the horizontal length of the wellbore.