With the information below and using our selection charts, the type and number of spacer elements required for each ring and how far they will be spaced can be determined.
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
CARRIER PIPE O.D.
Up to 280 mm or 11 in
Up to 1000 mm or 38 in
M/N or P/Q
Up to 3400+ mm or 134+ in
Our basic formuals below will help you choose the correct Raci Spacer element.
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.
TO CLEAR THE BELL
(carrier pipe O.D.) + (2 times height of element) > O.D. of bell + clearance factor* x 2
*Clearance factor is .6 inches or 15 mm and ensures bell clearance.
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.
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.