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CONTROL VALVE INTRODUCTION
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ACTUATOR SYSTEMS AND ANCILLARIES
The following general requirements shall be applicable The ABV
assemblies, including all ancillaries, shall have a minimum nominal
design life of 20 years based on Seller's recommended maintenance
procedures being followed during this period. For all actuated valves
this shall correspond to a nominal minimum design limit of 1000 cycles.
Materials of construction shall be suitable for achieving the above
design life in a corrosive offshore or coastal environment. Seller shall
specify in his quotation, materials of construction for all key
components of the actuator assembly and ancillary equipment. Aluminium
components shall not be specified for actuators or ancillary equipment.
The actuator type shall be as specified in the requisition. In general
actuator type selection shall be based on the following order of
preference.
Shutdown Valves and Blowdown Valves. (SDV's and BDV's) shall preferably
utilise pneumatic, single acting, spring return actuators. Where space
or torque limitations preclude the use of this type of actuator the
following types may be specified.
- Hydraulic, single acting, spring-return
- Hydraulic, double acting
- Pneumatic, double acting
Electric motor operated or hydraulic/pneumatic motor operated or double
acting actuators may be specified for MOV's The nominal closure time for
SDV's shall be 1 second per 25 mm of nominal size with a maximum of 45
seconds The maximum closure time for MOV's shall be two (2) minutes.
On loss of holding signal, or on loss of pneumatic/hydraulic pressure,
SDV's shall revert to the closed position and BDV's shall revert to the
open position. Accumulators for double acting actuators in SDV or BDV
service shall be close coupled to the actuator .Alternatively the
accumulator system may be shipped loose and located in a no vulnerable
area remote from the actuator providing that hydraulic/pneumatic supply
and return
lines to and from the actuator are suitably protected against
fire/-explosion damage.
Actuators shall be sized to provide the following torque value based on
the requirements of a new value, at all points of its operating cycle,
from fully open to fully closed and vice-versa. The required actuator
torque shall be a minimum of 1.25 times the manufacturers maximum
specified torque value at a pressure differential across the valve-equal
to the full ambient
temperature rated pressure of the valve. The valve torques shall be
based on infrequent useage of approximately one cycle every 3 months.
For SDV's, the above actuator torque shall be based on the specified
minimum pneumatic or hydraulic supply pressure. For electric MOV's this
shall be based on the minimum specified
supply voltage.Unless otherwise stated the
minimum pneumatic supply pressure for operation shall be taken as- 5.5
barg. When specified in the purchase requisition, the valve/actuator
assembly shall be provided with electrical limit switches which will
indicate when the valve is either in the fully open or fully closed
position. The switches shall be proximity type (preferred) or
mechanically operated hermetically sealed rated for 0.5A at 24V DC. The
switches shall be SPDT and shall utilise a 20mm ISO single electrical
entry. Protection shall be to IEC-529 IP 65 and the switches shall be
suitable for inclusion in an intrinsically safe circuit.. Proximity
switches shall be configured such that metal is detected when the end
position is reached. Mechanically operated switches shall be configured
such that the contacts are open when the valve is in the appropriate
fully open or fully closed position and closed when the valve is
stroking.
All valve/actuator assemblies shall be provided with direct coupled
mechanical position indication devices.
For all ABV's the valve stem shall be sized such that it can not be
subjected to torsional stresses in excess of that permitted by the valve
manufacturer with the pneumatic/ hydraulic supply at its specified
maximum pressure. Where actuators are to be retrofitted to existing
manually operated valves, actuators shall be sized such that the stem of
the valve cannot be overstressed. This may, however, be permitted, with
prior Company approval, providing that the pneumatic/hydraulic supply to
the actuator is provided with a suitable pressure regulator and relief
valve to limit the torque to an acceptable value.
This criteria shall also be applicable if the MAWP of the actuator body
is below the maximum stated air supply pressure. The ABV assembly shall
be capable of being orientated in any direction with no external
supports, Mounting details shall be such that no undue stresses are
imparted to the actuator or valve shaft/body regardless of orientation.
Pneumatic/hydraulic actuator bodies shall be of integral or all
flanged/bolted construction. The use of pressure containing external tie
bar construction shall not be permitted. For pneumatic and hydraulic
actuators an adjustable restriction device shall be provided in the
supply line to the actuator to enable the opening line to be adjusted.
All actuators and ancillary equipment shall have a minimum ingress
protection to IEC 529,1P 65. Where actuated valves are specified for
installation in the splash zone offshore, protection shall be to IP 66.
Where actuated valves are specified for sub-sea installation, protection
shall be to IP
67 or 68m as applicable. Instrumentation for packaged ABV's.
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Marshalsea Hydraulics Shutdown valve Open this result in new window
Marshalsea Hydraulics develops and supplies
hydraulic equipment for the international offshore oil and gas industry for
both subsea and topside applications. shutdown valve Type 1175 is a
pilot-operated, three port, two position poppet valve with a spring-return
action. Manufactured from materials complying with NACE Standard ASCO - 3
WAY AIR PILOTED SPRING RETURN - SHUTDOWN SYSTEM ASCO is the worldwide leader
in the design and manufacture of quality solenoid valves. ASCO products are
designed to control the flow of air, gas, water, oil, steam. Please let us
address your applications. standard, low power and intrinsically safe.
Applications. For emergency shutdown of a process control valve the solenoid
valve in the signal Standard and Low Power valve with or ...
www.psidenver.com/asco/zero.htm
Rupture Pin Technology
EMERGENCY SHUTDOWN VALVE. Model "A" Emergency Shutdown Valve. Model "B"
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Showing A Standard Design For Valves Standard Features 200 gallon, 300 psi
W.P. @100° F USCG design Product Name: Standard Features. Product
Description 100° F USCG design. 1" relief valve with block valve mode
is overridden by emergency command. Emergency shutdown is immediate Film
Bearing Design and Analysis. Valve Design and Analysis hydraulic
spool/poppet valve) for Hamilton Standard. Performed time-transient startup
and shutdown torsional vibration ...
www.nobullengineering.com/principalsandstaff_mcorbo.html
PMB Product:
Heavy-duty wraparound frame with one-inch tubing and low-profile, compact
design OHV engine with low-oil shutdown. · Brushless 120V/240V alternator. ·
Fuel shutoff valve standard.Flood Prevention - the CWD MultiZone Valve
Shutdown System from Aqualeak CWD in standard form can provide water
shutdown via the designated shutdown relay', this requires the valve/s to
multiple valves as required by any specific project design SuperSafe Tanks
Inc. - The Technological Leader in Safety, Performance, and Environmental
Protection in its design and assembly. These standard features include level
hydraulic valve built to ANSI B16.5 Standard and meets NFPA-30 2-10.1.1
Emergency independent shutdown system www.supersafetanks.com/standard2.html
ASCO - 3 WAY AIR PILOTED SPRING RETURN - SHUTDOWN
SYSTEM Zero Minimum Air and Inert
ASCO is the worldwide leader in the design and manufacture of quality
solenoid valves. ASCO products are designed to control the flow of air, gas,
water, oil, steam. Please let us address your applications. ... standard,
low power and intrinsically safe. Applications. For emergency shutdown of a
process control valve the main valve. Standard Constructions Standard and
Low Power valve with Small Engine - 21 HP Vanguard, Horizontal Standard at
SHOP.COM Buy Small Engine - 21 HP Vanguard, Horizontal Standard Tapered
Shaft, Right Side Muffler, Key Switch, Oil Cooler 381447-0275 and other
Tools & Workshop products at SHOP.COM. Overhead Valve Design Cast Iron
Cylinder Sleeve Horizontal Mounting Electric Starter Low Oil Shutdown
Tapered Shaft .
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