• Brian Ennever Managing Director
Autonomous Shutdown Valve
for Subsea PLEM Valves
Typical CALM Buoy System
Typically used in shallow water applications down to 245m without requiring pressure compensation
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Central Pipe Swivel
Floating Hose
Submarine Hose
Anchor Chain Leg
PLEM
Pipeline
The Problems
• Umbilicals provide actuator’s hydraulic supply pressure
• Umbilicals provide electrical signalling and partial closure testing control
• Umbilicals are prone to wear and tear and damage
• In the event of umbilical failure, all remote control is lost
• Valve control via diver or ROV intervention are the only options following umbilical failure
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Operation Without Autonomous
Shutdown Valve (ASV)
• Manual PLEM valve
• Expensive diver interventions required for each tanker visit
• Valve operation in fair weather only • Actuated PLEM valve
• Operated by HPU on surface buoy
• Unsatisfactory system availability due to dependence on offshore visits
• Reliability issues due to complex and fragile control system
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Operation Without ASV
• Actuated PLEM valve - continued
• No Emergency Shutdown (ESD) facility
• Control is reliant on a telemetry link as
opposed to hard wired
• Requires frequent trips to buoy for checking
and recharging of Hydraulic Power Unit (HPU)
pressure
• System availability issues
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ASV System Overview
• Electro-hydraulic system
housed within an oil filled
pressure compensated
pod
• Pipeline pressure acts on
barrier vessel, pipeline
pressure on one side
converts to control
pressure on the other
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ASV System Overview
• Operates on a mineral or
biodegradable fluid within
a sealed system
• Actuator powered via a
high flow pilot valve
• Pilot valve controlled by 2
solenoid valves
• Manifolded system 7 of 15
Communications
• Cable connecting to surface buoy to
provide: • Remote status indication
• Simple health checks
• Manual override function
• In-situ diagnostics and configuration
• Communications are via a RS link and
normally via a connection on the
surface buoy
• Data can be transferred by any
appropriate highway 8 of 15
Communications
• Standard monitoring data includes:
• Pipeline pressure
• Valve position status - open/closed/
intermediate
• Solenoid valve status - energized/de-
energized
• Number of completed valve operation
cycles
• Pressure sensor health
• Solenoids health
• Battery health 9 of 15
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Communications
Electronics Package
• Batteries have a 20A/Hr
capacity
• 8 Bit micro controller
• Internal watchdogs give 1:115
time ratio to conserve battery
power
• Expected life 7/15 years, 5
years guaranteed based on 3
operations per week
• Rechargeable battery option
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Double-Acting Actuator Option
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ASV HIPPS
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Operator Concerns
• Improving Reliability
• Reducing OPEX
• Increasing Environmental
Protection
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Contact information
• Brian Ennever, Managing Director
• Paladon Systems Ltd.
• Tel. +44 (0)1604 880700
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