Suggested Pipeline Casing Standard

 


 

 


The following pipeline casing standard is presented to eliminate problems that could occur in the
field and in order processing.


Casing Filler
 

Temp. of Filler During Installation:

175ºF - 225ºF

Pressure of Filler During Installation:

10 psi max.

Weight of Filler: 

7.1 lbs per Gallon

 

Casing Spacers
 

Model:

C12GN-2 CR Symmetrical Design

T.P.E. Liner:

275ºF

Band Configuration:

2-Piece

Position: 

CR 1.5” Top Clearance (Tolerance ± 0.25”) Symmetrical Design
Body of the Installation

For Illustration Purposes Only
   
   

Position: 

CR 1.0” Top Clearance (Tolerance +/- .25”) 2 Top / 4 Bottom
For ends of the Installation. For use with modular seals.

For Illustration Purposes Only
Note: Temperature range for C12GN-2 should be considered.

 
Casing Spacer Design Considerations:

Modular seals require a centered and restrained design (CR), and must be placed at both ends of the casing. A symmetrical design, SYM (the riser/skids are positioned at the same number of degrees around the carrier pipe and all are the same length) is ideal for the main part of the bore.

Calculations for a typical (16” carrier x 24” casing) bore:

For symmetrical design - SYM:
23.25” - 1.5” clearance  = 21.75” - 16” carrier = 5.75” divided by 2 = 2.785” - 1.7" effective skid height = a riser height of 1.25”.

 
For CR design:
23.25” - 16” = 7.25” divided by 2 for centering = 3.625” - 1.7” effective skid height = 1.925” meaning a 2” high riser on bottom.

 
To get the top riser height:
 23.25” - 1” clearance = 22.25” - 16” carrier = 6.25” - 1.7” - 1.7” - 2” bottom riser = 0.85” meaning a 0.75” top riser.

We do NOT suggest a symmetrical & centered /restrained design over the length of the casing because of concern that the carrier pipe will bind in the casing with such a small amount of clearance. Our standard recommendation is 1.5” clearance at the top.

We recognize the expressed concern about mixing up the proper spacers in the field. We suggests that this concern be addressed in the way the spacers are marked and packaged. SYM and CR Spacers for use with modular seals will be shipped on a different pallet and marked to indicate use.

 

Modular Seals
 

Model:

Model C (Black EPDM)

Temperature:

-40 to 250ºF

 
For Illustration Purposes Only

 

End Seals
 

Model:

W – Wrap Around (Black EPDM 60).
To be used on each end of Casing.

Temperature:

250ºF

 

For Illustration Purposes Only
Note: After Model W has been installed,
slurry backfill will be applied 24 hours later

Ordering - Casing Spacer Nomenclature
Purchasing material to be ordered through Farwest.

Casing spacers, modular seals and end seals should be purchased through Farwest. A designated call sign will be added to the end of the Casing Spacer Ordering Code (Nomenclature). This will identify the casing spacers needed for the new casing standard.

C12GN-2 16” x 23.25” - 0” CR SYM
The SYM indicates the Spacers needed for the body of the installation.
(T.P.E. Liner, CR 1.5” Top Clearance (Tolerance ± 0.25”) Symmetrical Design). Spacers positioned standard 8 feet.

C12GN-2 16” x 23.25 - 0” CR
The CR indicates the Spacers needed for the ends of the installation.
Quantity of 4 must be ordered, T.P.E. Liner, CR 1.0” Top Clearance (Tolerance ± 0.25”) 2 Top / 4 Bottom for use with Link-Seal modular seals. Spacers positioned 2 at each end, at 8” from edge of casing, and then at two (2) feet from end spacer.

 

Visual Overview

Graphic is for discussion and illustration purposes only.

Casing filler is delivered to the jobsite via tanker trucks that are heated and insulated.

Installation