In onshore and offshore oil and gas, operators' demand for components that satisfy a reduction in leakage paths resulted in our designing the Monoflange valve, combining primary and secondary valves into one compact unit. Integrating piping and instrument valves into a single unit delivers cost and safety benefits to the oil and gas, petrochemical, and chemical markets.
The Monoflange has a needle valve primary and secondary rather than ball valves. The result is a lower system mass, which reduces loading and vibration stresses, further improving safety and reliability. Being smaller than a traditional double block and bleed valve, gives even more space and weight advantages. This ensures that the Monoflange valve is a cost-efficient option for both owners and operators.
Let's take a look step-by-step at how to safely remove a plugged process to instrument Monoflange using our integrated Monoball solution (with captive studs screwed into the drilled and tapped holes in the Monoball) to enable the processing pipeline to continue operation. For this example, the application is using a close-coupled Monoflange with an integrated Monoball. This enables the process pipeline and service to continue while the Monoflange is being serviced or replaced. This unique product combination allows the process to continue with no loss of production, increasing uptime.
Step 1 - To ensure the safe removal of the Monoflange valve, we will isolate the Monoball valve by turning the handle 90 degrees - this will prevent any process media from escaping to the atmosphere while the Monoflange is absent.
Step 2 - To ensure all media is vented, open both the Monoflange block valves ( Primary and Secondary) and finally turn the vent on the Monoflange anticlockwise. This will remove the trapped volume of liquid or gas between the process and the instrument in a controlled manner. For substances such as H2S, an integral tube fitting and tube can be used to ensure safe removal.
Step 3 - Remove the four top nuts and washers with a spanner/wrench. This will allow the operator to remove the Monoflange and transmitter from the Monoball for transfer to the service workshop to clean or replace the Monoflange.
Step 4 - In the service workshop, the maintenance team will remove the transmitter for calibration (if required) and either clean or replace the Monoflange.
Step 5 - Return the Monoflange and transmitter to the Monoball.
Step 6 - Retighten nuts with spanner/wrench.
Step 7 - Open the Monoball valve to return to normal working conditions.
Watch this video and see all the steps to safely removing a plugged Monoflange valve by using a closed coupled Monoball valve arrangement.
This helpful support content was contributed by the Instrumentation Products Division, Parker Hannifin.
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