Effective Tension

= "effective tension" at one single depth, 'x'

Effective tension is the sum of the moments at a depth in a tube. It is called tension only for convenience. In the below sketch and development, the lever arm, a, is assigned a value of unity for convenience, and because its true value can not be known or computed. Thus, effective tension is the force component of a moment. Treaj is ascertained with a free body and the setting of the sum of forces acting on the free body to equal zero.

Whereas, Te£p is ascertained with a free body and the setting of the sum of the moments acting on the free body equal to zero and then setting the lever arm equal to unity.

With the sketches Trea] is

-Treal + W + P^ - Pb()A0 - WOB = 0 and also with the sketches M is

M = + Wa + [Pbi Ai - Pb0 A0 ] a + [Pt0 Ai - Pti A0] a - WOB a

Considering Af^ to be negligible, setting a = 1.0, and Teff = M, then

Effective Depth Top Reinf

which is the effective tension at the top of the section. Note that tensions, pressures, and areas must be computed at one single depth. For example, 8,984 feet could be the chosen depth.

BUOYED WEIGHT

Note that if w^ is the weight of the fluid inside the pipe per unit length, w0 is the weight of the fluid displaced by the pipe, and wg is the weight of the steel per unit length in the wall of the pipe, then the effective weight of the pipe is weff = ws + Wj - w0 = "effective weight" (21a)

All variable in oil field units: lb/ft, lb/gal, inches. This is also called "buoyant weight" or "weight in mud", etc.

The buoyed weight of pipe at a specified depth is the buoyed weight per unit length of the pipe multiplied by the length of pipe below the depth.

Was this article helpful?

+2 -4
Homeowners Guide To Landscaping

Homeowners Guide To Landscaping

How would you like to save a ton of money and increase the value of your home by as much as thirty percent! If your homes landscape is designed properly it will be a source of enjoyment for your entire family, it will enhance your community and add to the resale value of your property. Landscape design involves much more than placing trees, shrubs and other plants on the property. It is an art which deals with conscious arrangement or organization of outdoor space for human satisfaction and enjoyment.

Get My Free Ebook


Responses

  • patryk mcmillan
    How to calculate the effective tension in drilling?
    8 months ago

Post a comment