VALVES AND MANIFOLDS DATA SHEETS

Application

• For isolating, calibration and draining (venting) pressure gauges and transmitters

Using the Isolate & Bleed Valves

• In normal operation the “isolate” valve is open while the “vent” valve is closed
• To remove the instrument, first close the “isolate” valve, then open the “vent” valve to relieve pressure upstream of the “isolate” valve

Calibration option

• By connecting a test gauge to the vent port, it is possible to check the calibration of the installed instrument without removing it from the installation 

Stewarts 3-Valve manifolds are precision-machined in 3 basic design configurations. For single line flow, the double block bleed (DBB) manifolds provide maximum safety and reliability for more hazardous situations. For a differential dual line flow there is the single block and equalise – which is ideal for calibrating and zero-ing differential measurement instruments or for other isolation and equalisation of system sections.

And for a differential flow, there is the single block and equalise with vent plug connections which provide a means to relieve downstream pressure on either side after isolation – and again this is used for zero-ing and calibration functions. This is ideal for performing various maintenance, testing and sampling functions with a high level of safety and reliability.

Application

• For applications such as measure flow or level using a differential pressure transmitter or gauge with a calibration facility.

Using the Differential Filter 3 Valve

• In normal operation the “isolate” valves are open while the “equalise” valve is closed
• This provides a differential pressure medium to the pressure gauge or transmitter
• To zero the instrument, first close the downstream “isolate” valve then open the “equalise” valve and adjust the zero settings on the instrument
• To remove the instrument, first close both “isolate” valves, then unscrew the vent (drain) plugs normally fitted to the instrument to relieve pressure between the manifold and the instrument

Application

• For applications such as measuring flow or level using a differential pressure transducer or gauge with calibration and instrument removal facilities

Using the 5-valve manifold

• In normal operations the “isolate” valves are open while the “equalise” and “vent” valves are closed. This provides a differential reading to the gauge or transmitter
• To zero the instrument, first close both “vent”valves and the downstream “isolate” valve. Then open the “equalise” valve and adjust the zero settings on the instrument
• To remove the instrument, first close both the “isolate” valves, then open the “equalise” valve followed by opening both “vent” valves to relieve pressure between the manifold and the instrument

Calibration option

• An option provided by 5-valve manifolds which is not available on 3-valve types is connecting the “vent” port to known pressure sources to check the calibration of the instrument

The integral SWIVEMAS® is available in various other of our 1, 2, 3 and 5 valve manifold models, flanged or hub connection.

Swivemas® Application

• Helping power stations, process plants and the oil and gas industry to reduce leak paths in pressurised systems, thereby reducing potential fugitive emissions in accordance with the EU’s IPPC Directive 2008/1/EC.

The Stewarts E2, E3 & E5 Series manifolds are manufactured for applications that require the transmitter to be mounted in an enclosure for environmental protection. Although our standard transmitter manifolds will work, the ‘E’ series is designed to save space and to simplify the mounting of the transmitter in the enclosure. Additionally, the ‘E’ series presents the valve handles for easy operation of the valves. Process connections, and mounting holes are situated on the bottom of the manifold to simplify piping.

Application

• For medium and high pressure applications in the oil and gas, petrochemical and other general industries

How to order

• See – How to order needle valves & manifolds

Additional Sizes

• additional sizes and options are available on special request

BALL VALVES & MANIFOLDS