Jonathan Strickland and Courtney Richardson, Oxy
Jonathan Martin, Black Mamba Rod Lift
Since becoming a Lift Specialist in November of 2019, it was very clear we had significantly higher failure frequencies on wells with 4.5” liner, 2 3/8” tubing, and 1.75” tubing pumps vs other configurations. My knowledge is solely based on South Plains and the problems we faced.
One of my counterparts had reached out to the pump shops to understand how we could beef up pull rods. It was discovered that a 1 1/16” pull rod could be ran in 1.75” and 2.00” insert pumps. We began taking this route immediately. This got me thinking…What could be ran in a tubing pump to help beef up the pull rod/stabilize it better? We had a few different options that had been done in the past. Land the pump barrel in tension above the TAC to create better stabilization vs. leaving the pump at the bottom of the hole allowing for movement. We could change our pull rod and increase the diameter from 7/8” to a 1.25” sinker or polished rod for more durability.
Several weeks later we went on a field trip to a pump shop and I noticed a small Black Mamba guided rod on top of one of their racks. It was a ¾” rod with guides fitted for 2 3/8” tubing. Immediately I knew there was no way any conventional guided rod would scope in and out of a tubing pump barrel, but asked myself; could this be retrofitted to work since the entire rod is basically a guide? A Mamba rod cannot buckle due to the end-to-end rod control that 7-per Mamba rods provide. There should be less erosion tendencies downstream of the guide due to the pattern of flow (vortex vs. conventional vertical flow). The vortex movement of fluid discharging at the pump should help keep gas in solution similar to the tangent flow cages we had tried in the past in insert pumps. Compression in tubing pumps was something we continued to struggle with in CO2 floods. I said to myself, “Self, this just might work!”
I thought on the subject for about a week and decided to voice my idea to the QA group. We then got in touch with Black Mamba to see what could be done to test my theory. Black Mamba was very enthused and on board with designing to our needs. They ran computational fluid dynamic simulations (CFD) to help determine the best flow options for Black Mamba guided rods, comparison also to large diameter sinker bars. It was agreed to run 1” Mamba sinker rods above the pump, and to use mamba guided rods at every taper break (4 mambas each side of the taper break in every taper) in conjunction with the plunger stabilizer rod, a unique dimension Black Mamba guided 3/4” Norris N90 (DS/KD) sucker rod.
I had already began collecting data prior to this idea. The data I pulled on 88 wells with tubing pumps was to determine the best design of landing the pump barrel in tension above the TAC or at the bottom of the tail pipe. Failure mechanisms were primarily split barrels and broken pull rods due to wear or coupling breaks. Preliminary results showed that the barrel in tension had significantly longer RT than the barrel landed below the TAC (> 2 years on average). Understanding there could be some production loss associated with raising the pump above the TAC, how do we balance production and longevity? Was there a way to get the best of both? Either way, the answer was the pump should be stabilized to gain the best results.
10 wells feature an End-to-End Rod Control Pull Rod from Black Mamba. Design and application results will be reviewed.