Scribd
Upload
134 views1 page

2.3 Pressure, Flow and Level Control Valves: Section 2.7.5

This document provides guidelines for installing line valves, isolation valves, and pressure/flow/level control valves. Key points include: 1) Isolation valves should be located off carriageways and intersections to avoid obstructing access. They can be installed in dry chambers, buildings, or buried depending on factors like maintenance access. 2) Remote operation and monitoring is used where quick manual isolation is critical or remote reconfiguration provides value in emergencies or planned works. 3) Isolation valves include bypass lines to allow recharging or draining the line on either or both sides of the valve depending on installation point.

Uploaded by

ObaidUrRehman
Copyright
© © All Rights Reserved
We take content rights seriously. If you suspect this is your content, claim it here.
Available Formats
Download as PDF, TXT or read online on Scribd
134 views1 page

2.3 Pressure, Flow and Level Control Valves: Section 2.7.5

This document provides guidelines for installing line valves, isolation valves, and pressure/flow/level control valves. Key points include: 1) Isolation valves should be located off carriageways and intersections to avoid obstructing access. They can be installed in dry chambers, buildings, or buried depending on factors like maintenance access. 2) Remote operation and monitoring is used where quick manual isolation is critical or remote reconfiguration provides value in emergencies or planned works. 3) Isolation valves include bypass lines to allow recharging or draining the line on either or both sides of the valve depending on installation point.

Uploaded by

ObaidUrRehman
Copyright
© © All Rights Reserved
We take content rights seriously. If you suspect this is your content, claim it here.
Available Formats
Download as PDF, TXT or read online on Scribd
You are on page 1/ 1

c) Line valves shall as far as practicable be located off carriageways, clear of intersections and not

obstruct property access.


d) Isolation valves are installed in dry chambers, above ground buildings or may be direct buried. The
installation location must be demonstrated to be the best practicable option with consideration to:
• The need for ancillary equipment such as actuators
• The means of access for maintenance and replacement of the complete unit or maintainable
parts such as gearboxes
• The type of valve being installed. Typically gate valves are best suited for buried applications
• The whole of life cost benefit for the proposed installation method
e) Remote operation by actuator and SCADA monitoring is used where response time for manual
isolation is critical, or remote reconfiguration of the system provides value such as in emergency
situations, or for planned works that can be arranged more efficiently. Refer to Watercare’s electrical
design standards for actuator design.
f) The main isolation valve shall include an isolation bypass to allow for recharge and/or draining.
Draining may require to be either side of the main isolation valve when installed at a low point, or
from the upstream side when installed in a sloping mainline. A double bypass isolation setup is
required to allow drainage from both sides of the main isolation at low points, or otherwise a single
bypass valve only is required.
g) Gate valves are used up to 300mm and geared butterfly valves for larger sizes.
h) For water pipes larger than 600mm the main pipe diameter may be reduced for economic benefit of a
smaller isolation valve but only if it is hydraulically feasible.
i) Valve trains installed in sequence shall be of the same size.
j) Bypass valves are typically smaller than the main isolation valve to facilitate mainline charging and
drainage. Bypass pipework up to 200mm shall be API Schedule 40 pipe.
k) The horizontal clearance between the main line and bypass shall be minimum 300mm at the closest
point.
l) Handwheels shall be 300mm clear of obstacles.
m) Where pipe reducers are used it shall be an eccentric reducer, tapering down from the bottom of the
pipe.

2.3 Pressure, flow and level control valves


a) Butterfly or gate valves shall not be ordinarily used for flow or pressure modulation. Fit for purpose
control valves shall be used.
b) Control valves shall typically be SCADA monitored and may require to be fitted with an actuator for
remote operation. Refer to Watercare’s electrical design standards.
c) Control valves shall be installed in an above ground building or dry chamber. The installation location
must be demonstrated to be the best practicable option.
d) Valve trains installed in sequence shall be of the same diameter, however where it may be considered
that a future upgrade will require the valve train to be up-sized the isolation valves may be selected to
be greater in diameter.
e) Isolation valves shall be provided at both ends of the installation, these may be direct buried outside
the chamber if of suitable valve type.
f) Duplicated control valve trains shall be provided with individual isolation at both ends.
g) It the installation is for a dual system (high flow with low flow) the bypass shall be provided to the
principal set only.
h) The horizontal free clearance between the mainline and bypass shall be minimum 300mm at any
point. Also see section 2.7.5 for general clearances.
i) Pipework shall be arranged to provide vertical lifts on equipment that require ongoing maintenance.
j) Control valve train isolation valves shall be fitted with handwheels.

Ver.1.1 This is an electronic ESF document that


is uncontrolled when copied or printed Page 42 of 70

You might also like