Black Mamba UPK

Unfilled Polyketone

Black Mamba UPK is a new and improved variant of our original Black Mamba geometry launched in 2020. Our triple bonded, single floating fin design continues to dominate the industry for its leading Erodible Wear Volume, Bearing Surface Area, Flow Area, and Flexibility.

The UPK (Unfilled Polyketone) material allows predictable, worry-free performance for wells operating with fluid temperatures up to 250 F. Intentionally unreinforced, the Black Mamba geometry combined with the UPK material creates a perfect marriage in product design, reliability and performance.

Black Mamba UPK is practically indestructible!

Critical Buckling Load

The Critical Buckling Load is the maximum compressive load a member can take before instability occurs. As compressive loads are applied to a sucker rod beyond the Critical Buckling Load, the column (rod) will move laterally (rod-into-tubing), creating instability and damaging the pumping system (sucker rod buckling).

By eliminating the lateral deflection of the sucker rod by way of Complete, Predictable, End-to-End Rod Control and constant stabilization and centralization through Black Mamba UPK and HydraHT, sucker rods are fully constrained within the tubing, allowing increased pumping speeds and velocities without fear.


With a single fin design combined with the coveted polyketone material, Black Mamba UPK is the ONLY molded sucker rod product in existence that truly does not inhibit sucker rod flexibility. The reduced cross-sectional area combined with our engineered material allows for unprecedented component flex and a complete elimination of bending moments along the sucker rod when used properly.


Relative Area Moment of Inertia
Lower value = greater geometric flexbility.
Monster Legacy (I = ~0.775)
Large Legacy (I = ~0.696)
Black Mamba (I = ~.294 max)
AMOI of Sucker Rod Guides and The Black Mamba

Relative Flow Area

Black Mamba UPK has achieved the near impossible by providing unmatched rod protection while achieving less flow restriction than a 3/4″ coupling.

Black Mamba UPK
3/4" Full Size Sucker Rod Coupling
4-Fin Legacy Sucker Rod Guide (Average)
Fluid Flow Bypass Area - Black Mamba - Sucker Rod Coupling - 4 Fin Sucker Rod Guide

S-N Curves

As repetitive stress magnitude increases, the number of expected cycles to failure decreases, resulting in a shorter life for the product. Although a rod string design may be engineered correctly for standard tensile loads on the up-stroke, during compressive moments, the rod string design rendered is no longer accurate.

The bending moments created during compression occur at the upset-forging to rod-body transition or at the edges of rod guides, and is THE reason for common rod parts and sucker rod failure. Of course, for all failures at these locations, corrosion will be a contributor, leading to the common definition of Corrosion Fatigue. High tensile stresses are present at the moment of deflection, and those stresses far exceed the long-time respected Modified Goodman Diagram which drives rod string design best-practices.

In sucker rod dynamics, one of the greatest improvements to the system is ELIMINATING BENDING MOMENTS and reduction of chaotic behavior. With Black Mamba UPK, sucker rod behavior during compression (which cannot entirely be eliminated) is managed.

By preventing bending moments, localized stresses and pre-mature fatigue on the rod body, Black Mamba prevents the astronomical acceleration to fatigue failure caused by sucker rod buckling.