Jonathan Balmforth discusses environmental, hydrocarbon and contamination time delay return isolation.
When flammable well gases, including harmful substances such as hydrogen sulphide, escape from a downhole safety valve, they can cause severe environmental harm and pose serious safety risks. The safety concerns involve potentially explosive environments. If these flammable gases reach the topside hydraulic power unit (HPU), there is a potential for explosion that may potentially be fatal to a rig worker. Problems can also occur if control lines are unexpectedly pressurised; this may affect the function of other valves in the system, resulting in safety shutdown valves being triggered.
To help tackle these issues, JB Valves has developed the Return Isolation Valve/Blocking Valve (BVTD) as a means of automatically preventing hydrocarbon or contaminated fluid returns from entering the control system and environment. This novel offering is a single item that fits in the palm of the user’s hand and can be installed topside or subsea.
The BVTD provides environmental hazard protection; it prevents the release of hydrocarbon gasses and chemicals to the atmosphere and sea. It has a simple in-line installation process, therefore no vent, tank or pilot lines are required. Further advantages include its compact and lightweight profile as well as the fact it is compatible with existing infrastructure.
Return of unwanted hydrocarbons and contamination to a control panel, SCM, manifold or HPU can be prevented with JB Valves’ time delay solution. The firm’s core application analysis centres around contamination and control line transmission of hydrocarbons.
The downhole safety valve (DHSV) actuator pilot line provides potential communication of hydrocarbons to the control systems and HPU; JB Valves’ solution safely isolates return migration. The company believes that venting to atmosphere, capture and disposal utilising the flare stack, should be measures of last resort. The BVTD isolates the hydrocarbons from the control systems, HPUs and environment, creating resilient and safe environmental protection.
Fluid cleanliness can impact control system life; the time delay isolation valve can be used to prevent further contamination of control fluids by physical separation.
The company has developed a product that can easily be retrofitted within legacy or repurposed infrastructure and enhance existing field equipment. The BVTD can be installed simply inline, with zero circuit impact, protecting control equipment and isolating potential hydrocarbon exposure.
What is the function?
The time-delay return isolation valve is a single, simple inline valve. Open position
is achieved by applying line pressure from 20-1,379Bar. In the pressurised state
the valve remains fully opened; once line pressure is reduced, the valve closes after a predefined time delay preventing locked pilot pressure. As the line pressure is re-applied the valve returns to a fully opened state allowing for communication. No pilot, vent ports or tank lines are required and no additional accumulation.
Fundamentally, JB Valves believes that a product should be environmentally conscientious with the minimum amount of leak paths and emissions. Part of its design philosophy is to consider where weight and space can be saved while producing the most robust and innovative solutions.
Jonathan Balmforth is managing director of JB Valves.