Over 25 years of playing with shallow stripper wells has led to a few conclusions (and much less money than other pastimes might have yielded). The shallow wells under discussion here are typically less than 1000 feet in depth, but the same principles can probably be applied to wells somewhat deeper. One fundamental assumption that can be made about most stripper wells is that fluid yield is head sensitive. That is to say, as the fluid level or head builds up, the oil production rate goes down, until the well reaches equilibrium and is yielding no fluid to the well bore. It is not unheard of for stripper wells making a barrel or two of oil per day, to almost completely cease to produce when the tubing is raised less than one joint (your author once consulted on a well where less than ten feet made the difference between three bopd and almost no production).|
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Logically then, we must maintain as low a fluid level in the well bore as possible to maximize production. The shallow wells under discussion can be pumped continuously if they make more than ten or so bpd total fluid with no damage to the pumping equipment. Fluid pound will not harm surface pumping structures on such shallow wells, and in fact the "pop in the stroke" used by pumpers of shallow wells to tell if the well is pumping properly is fluid pound. It is common practice in old shallow waterfloods to pump producing wells 24 hours a day. In wells making small amounts of total fluids, the same logic applies. Try a 15 minute time clock and pump the well a few minutes several times a day as opposed to say one hour, once a day; the difference in daily production can be considerable.
A more recent revelation has been the importance of using pumps configured for the highest practical compression. Except in unusual circumstances, double ball and seat pump configurations should be avoided; double balls and seats generally cause more problems than they cure. For more detailed information on high compression technology, see
Sucker Rod Pump Gas Lock. Almost all wells benefit in some way from configuring pumps to maximize compression, but in some cases it can make a big difference in production.
It is common practice in this area to set the pump intake just above the shot hole in open hole completions, or just above the perforations in more modern style completions. The underlying logic is to prevent atmospheric contact with the formation or perforations. Minimizing such contact may reduce scale growth and biological fouling. There are opposing opinions.
We generally recommend against closed bottom mud anchors unless you actually intend to tag bottom with the anchor. Closed end mud anchors are another "innovation" that typically cause more problems than they cure.