Concrete Cylinder Pipe (PCCP) is a rigid pipe
designed to take optimum advantage of the tensile strength of steel and of the
compressive strength and corrosion inhibiting properties of concrete.
PCCP is designed and manufactured in accordance with American Water Works
Association Standard C301.
PCCP is produced in Saudi Arabia in diameters of
4000 mm in laying lengths of 7.5 meters. Smaller
and considerably larger sizes can be produced.
It has been used for over 40 years for such applications as water
transmission and distribution pipelines, cooling water systems, sewer force
mains, inverted siphons, sub aqueous pipelines, and liners for pressure tunnels.
PCCP is designed by a proven analytical method which
considers all elastic and inelastic deformations in the pipe and conservatively
limits tensile and compressive stresses for any combination of internal pressure
and external load. A typical design
curve is shown, the most economical design being one which falls on the curve.
The overload curve, also shown, provides for live loads, water hammer or
other transient loads.
The operating pressure range for pipe 900 to 4000 mm in
diameter is shown for one and two layers of pre-stressing wire.
Pipe can be designed and manufactured for operating pressures higher than
shown with three or more layers of pre-stressing wire.
Ameron provides the customer’s engineer with a complete
engineering package for each PCCP project. This includes pipe design
calculations and fabrication details for each item furnished.
For complicated lines and industrial installations, a pipeline layout is
provided showing each component’s location.
Each component is numbered to identify its position in the line.
Fittings, fabricated at the PCCP pipe manufacturing
facility, are designed to avoid the need for cutting and fitting in the field.
Almost any size or configuration of fitting can be furnished to satisfy
the requirements of the system.
PCCP is rapidly and economically installed by means of
self-centering steel joint rings sealed with confined rubber rings.
The reliability and water-tightness of this type of joint has been proven
by 50 years of field experience. The
double rubber rings permit pressure testing of each joint as the pipe is
installed, thus assuring its water-tightness.
Installation rates of 30 to 50 pipe sections per day per installation
crew are frequently obtained.
Changes in Direction
Long-radius curves and minor changes in pipeline alignment
and grade are accommodated by deflecting the pipe joints or by using pipe
sections with ends beveled up to 5 degrees.
For short-radius turns, fabricated elbows are provided.
Restraint of Thrust
Hydraulic thrust in the pipeline can be resisted by field
welding the joint rings of assembled sections for a sufficient distance each
side of the thrust point to develop the required longitudinal restraint.
This method eliminates the need for expensive and sometimes unreliable
concrete thrust blocks.
Corrosion of steel elements in PCCP is inhibited by a
passivating iron oxide film which quickly forms and is maintained in the highly
alkaline concrete or cement-mortar encasement (pH at least 12.5).
As a supplemental protection, all pipe and fittings are coated with
The smooth interior surface of PCCP provides hydraulic
carrying capacity with a Hazen-Williams flow coefficient in the range of C=140
to 150. Because concrete does not
corrode, the carrying capacity is not decreased by age.
The rigid construction of PCCP makes it highly resistant to
physical damage and eliminates the possibility of vacuum collapse.
Because of this high load-carrying capacity, PCCP is not dependent on
lateral soil support, and therefore bedding and backfilling procedures are much
less stringent than for flexible pipe.