S01 / How it works hero
The anti-buckling mechanism

The physics, the model, and the loop.

Where sucker rod buckling actually happens downhole, the fluid pound and gas locking signatures that precede it, and how the closed-loop VSD retunes the well in under a minute.
Defined

Sucker rod buckling is what happens when the bottom of a rod string is pushed into compression on the downstroke: the rods bow and wrap into a helix against the tubing wall, and every stroke wears couplings and tubing until rods fatigue and part.

Field guide · sucker rod buckling →
In a sentence
6–14d
early detection
< 0s
loop closes
0
parted rods · design target
0
patents on the method
jump to the loop ↓
S02 / The physics, drawn
schematic · buckling sequence
FIG. 07 Buckling sequence, section detailsThree section details of a sucker-rod string in tubing: compression at the bottom of the string on the downstroke, helical buckling against the tubing wall, then tubing wear at the couplings and a parted rod.FIG. 07BUCKLING — SEQUENCE01A–AAA02B–BBB03C–CCCCSGTBGCPLGRODNEUTRAL POINTTENSIONCOMPRESSIONCONTACTWEARPARTED RODDWG FIG. 07SCALE NTSSRABS
FIG. 07 Buckling sequence, section detailsThree section details of a sucker-rod string in tubing: compression at the bottom of the string on the downstroke, helical buckling against the tubing wall, then tubing wear at the couplings and a parted rod.FIG. 07BUCKLING — SEQUENCE01A–A02B–B03C–CTENSIONCOMPRESSIONNEUTRAL POINTPARTED ROD
Phase 1

Compression at the bottom

On the downstroke, fluid drag and plunger friction push the bottom of the string into compression. Rods are built to pull, not to push.
Phase 2

Helical buckling onset

Past a critical load the compressed rods bow and wrap into a helix against the tubing wall. Every stroke, thousands of feet down, unseen.
Phase 3

Tubing wear → failure

Every helix rubs. Couplings wear through the tubing, rods fatigue and part, and the well goes down for a workover.
S03 / Detecting it

A buckling card has a signature.

Buckling bends the dynamometer card in a way a healthy pump never does: the downstroke load line sags where the string goes slack into compression. Brain’s classifier is trained on that shape, so it flags buckling from the surface card alone. No downhole sensor required.
See the classifier ↗
Healthy
Healthy dynamometer card040801200481216LOAD klbPOSITION in
Buckling
Buckling dynamometer card040801200481216LOAD klbPOSITION indownstroke load line sags
S04 / The control loop

Sense → Decide → Act → Verify · every minute.

Runs within the guardrails you set. Flags the exceptions only when you need to know.
schematic · control loop
FIG. 08 Closed control loopClosed control loop: Echo senses the well, Brain decides within the guardrails you set, the VSD acts on the new setpoint, the pump's next card verifies the result, and the loop closes in under 60 seconds.FIG. 08CLOSED LOOP< 60 sGUARDRAILSsetpoint01SENSELTECHO02DECIDEUCAIBRAIN03ACTMVSD04VERIFYPUMP
FIG. 08 Closed control loopClosed control loop: Echo senses the well, Brain decides within the guardrails you set, the VSD acts on the new setpoint, the pump's next card verifies the result, and the loop closes in under 60 seconds.FIG. 08CLOSED LOOP< 60 sGUARDRAILSsetpoint01SENSELTECHO02DECIDEUCAIBRAIN03ACTMVSD04VERIFYPUMP
S05 / FAQ

Questions engineers ask.

Why do sucker rods buckle?

Because the bottom of the string goes into compression on the downstroke. Fluid drag and plunger friction resist the plunger’s fall and push the lowest rods instead of pulling them. Rods are built to pull, not to push: past a critical load they bow and wrap into a helix against the tubing wall, every stroke, thousands of feet down.

Where in the rod string does buckling happen?

At the bottom, just above the pump. On the downstroke the upper string stays in tension under its own weight, while the lowest rods are pushed into compression. That compressed section is where the helix forms, where couplings wear through the tubing, and where rods fatigue and part.

Can you detect rod buckling from a surface dynamometer card?

Yes. Buckling bends the dynamometer card in a way a healthy pump never does: the downstroke load line sags where the string goes slack into compression. SRABS Brain’s classifier is trained on that shape, so it flags buckling from the surface card alone. No downhole sensor required.
See the classifier →

What does an anti-buckling rod pump do differently?

It keeps the rod string in tension at every stroke, so the bottom of the string never goes into compression and has nothing to buckle. The SRABS Pump is a drop-in anti-buckling rod pump: it solves buckling at the source instead of adding weight to fight it. The approach is peer-reviewed in SPE Production & Operations (2021).
The founding paper →

What is the difference between fluid pound and gas interference?

Both mean the barrel didn’t fill with liquid. In fluid pound the plunger falls through the empty space and hits the liquid on the downstroke, a shock load on the string. In gas interference the barrel holds gas, which cushions the fall and cuts what each stroke lifts. SRABS Echo sees the gas and the fluid level, and Brain adjusts speed and idle time before the pump starts to pound.

Does SRABS need a downhole sensor?

No. Buckling shows on the surface dynamometer card, and SRABS Brain flags it from the surface card alone. SRABS Echo, the fluid-level instrument, is an edge device: plug it in. No downhole sensor required, and no SCADA required for Echo.

Do I need to replace my SCADA?

No. There is no SCADA replatform. SRABS Brain reads your existing SCADA through a plug-and-play interoperable API and runs the well inside the guardrails you set: SPM range, fillage targets, kill conditions. It flags only the exceptions you need to act on, and the handle stays yours.

How does a pilot work?

One well, thirty days, then you decide. You loan us a well; we install at no cost, baseline it, run autopilot and hand you the data, which you keep. No procurement RFP, no SCADA replatform. If you want out, we hand the well back instrumented, with the data and the optimized setpoints.
Loan us a well →
Further reading