Choosing a Spacer
Selection Guidelines
The selection of spacer type depends on the following dimensions:
- exact carrier pipe O.D.
- exact bell, flange or coupling O.D.
- exact casing Pipe I.D.
- clearance desired between casing and carrier pipe
- length of application
- linear weight of filled carrier pipe
SIZE
CARRIER PIPE O.D.
RECOMMENDED SOLUTION
Small
Up to 200 mm or 7 in
Up to 280 mm or 11 in
S/T or C/D/I
A/B
Medium
Up to 530 mm or 20 in
Up to 1000 mm or 38 in
F/G
M/N or P/Q
Large
Up to 1750 mm or 68 in
Up to 3400+ mm or 134+ in
L
E/H
Formulas
Our basic formulas below will help you choose the correct Raci Spacer element.
Formula One
TO DETERMINE HEIGHT REQUIRED
Casing pipe ID – Carrier pipe O.D. / 2 will give you the desired range for element height.
Go to the table that best addresses the carrier pipe O.D. and load carrying capacity to determine the different heights that are available within that style.
Formula Two
TO CLEAR THE BELL
(carrier pipe O.D.) + (2 times height of element) > O.D. of bell + clearance factor*
*Clearance factor is .6 inches or 15 mm and ensures bell clearance.
Formula Three
FOR INSERTION EASE
(carrier pipe O.D.) + (2 times height of element) + clearance factor* < the I.D. of casing pipe
*Clearance factor is .6 inches or 15 mm and ensures insertion ease.
*When working in inches the clearance factor is .6
Once you have determined the element type and the height necessary return to the table to determine the number of elements required to complete a ring.
Formula Four
NUMBER OF RINGS REQUIRED
length of application / distance between rings + 3*
*The spacing of Raci spacer rings must ensure that the carrier pipe is fully supported throughout its length.
To guard against the effects of differential loading at the entrance and exit points of the casing, two rings are used at the beginning and end of the each casing, regardless of pipe size or length.
For more information, specifications or sales inquiries please contact us.
