If you’re an engineer, you’ll know all about the The PI (Productivity Index) / Inflow equation derived from Darcy’s law.
We won’t go into the detail now (more here on our well perforating systems blog if you’re interested) but in general terms, this is the formula which governs the productivity of wells based on a number of parameters which are intrinsic to the physical characteristics of the reservoir.
The main focus of the petroleum / production engineer in an effort to optimise well inflow is to reduce the overall perforation skin effect (St) which is a consequence of the combined perforation skin effects given by the following equation:
St= Sө + Sc + Sd + Sp + ∑Sdyn
Sө = Well bore geometry
Sc = Completion skin
Sd = Drilling invasion damage
Sp = Perforation skin damage
∑Sdyn = Dynamic skin effects
Reducing skin damage in the tunnel is consequently immensely important to perforating since any improvements in St has a large impact on the Productivity Index (PI).
What makes TriStim so special?
The importance of TriStim is that it has the potential to reduce skin all of the skin components described above with the exclusion of Sө.
Consequently, by minimising perforation skin damage TriStim can facilitate better flow of hydrocarbons from the reservoir into the well.
How does TriStim achieve this?
The objective for any perforation system is to establish an effective hydraulic communication between the wellbore and the formation (reservoir). Unfortunately, the processes involved in drilling & completing oil & gas wells have the unavoidable consequence of inducing damage to the near wellbore region.
TriStim has been specifically designed to deliver successfully in each of these four areas:
- Optimised combined tunnel geometry
- Reduced perforation damage effects
- Optimised reservoir coverage
- Maximised depth of penetration
In summary, TriStim will deliver a tunnel that has the best possible penetration to the reservoir because of how it focuses on reducing the effects of perforation skin damage.
Also, you can read more about the SPE paper 174194 ‘Understanding Perforation Geometry Influence on Flow Performance Using CFD’ that we co-authored over on our blog: New simulation results prove TriStim’s flow performance enhancing effects are repeatable.
The SPE paper demonstrates that ‘TriStim® convergent perforations show improvements to flow efficiency by up to 25%, skin reduction of up to 85%. PI is shown to increase by circa 50% over the standard HSD system.’