Difference between revisions of "Erosional velocity"

Revision as of 07:53, 27 April 2020

Erosional velocity is a velocity of the multiphase flow at which pipe erosion occurs.

Pipe erosion begins when velocity exceeds the value of

v=\frac{C}{\sqrt{\rho}}

where:

C

= empirical constant (starting erosional velocity), lb/s/ft2

\rho

= gas density, lb/ft3

API RP 14E (1984) suggested C=100 for continuous and 125 for non continuous service.

Erosion is normally expressed as a rate of metal loss, usually mm/year. It usually occurs in turns or protrusions; or with solids content.

One can relate Erosional velocity to a metal loss rate (see RP O501).

Mokhatab S, Poe WA, Speight JG (2006) "Handbook of Natural Gas Transmission and Processing", Section 11.6 - Design Considerations on sales gas pipelines, subsection 11.6.1 - Line Sizing Criteria, Elsevier, 2006.

@@ Line 7: / Line 7: @@
 :<math>v=\frac{C}{\sqrt{\rho}}</math>
-C/SQRT(ρ) in ft/s, where ρ = gas density (in lb/ft3) and C = empirical constant (in lb/s/ft2) (starting erosional velocity). We used C=100 as API RP 14E (1984) suggested C=100 for continuous and 125 for non continuous service.
+where:
+:<math> C </math> = empirical constant (starting erosional velocity), lb/s/ft2
-This is the empirical relationships for estimating whether erosion will occur in a system at a certain velocity used at [[:Category:PQplot|PQplot]].
+:<math> \rho </math> = gas density, lb/ft3
+API RP 14E (1984) suggested C=100 for continuous and 125 for non continuous service.
 ==Erosion==
@@ Line 17: / Line 18: @@
 One can relate [[Erosional velocity]] to a metal loss rate (see RP O501).
-== Nomenclature  ==
-:<math> C </math> = empirical constant, lb/s/ft2
-:<math> J_D </math> = dimensionless productivity index, dimensionless
-:<math> kh</math> = permeability times thickness, md*ft
-:<math> \bar{P} </math> = average reservoir pressure, psia
-:<math> P_{\bar{P}} </math> = average reservoir pseudopressure, psia<sup>2</sup>/cP
-:<math> P_{wf} </math> = well flowing pressure, psia
-:<math> P_{P_{wf}} </math> = average well flowing pseudopressure, psia<sup>2</sup>/cP
-:<math> q </math> = flowing rate, stb/d
-:<math> q_g </math> = gas rate, MMscfd
-:<math> T </math> = temperature, °R
-===Greek symbols===
-:<math> \rho </math> = gas density, lb/ft3
 == References ==