3 Valves Manifolds
Two isolation valves and one equalization valve, the standard solution for differential pressure instrument calibration and isolation
What Are 3 Valves Manifolds?
A 3 valves manifold combines two isolation valves and one equalization valve in a single machined block. It is used with differential pressure (DP) instruments to isolate the impulse lines from the process, and to allow equalization of the high and low pressure sides for zero calibration of the instrument.
The manifold is machined from solid barstock or forged, eliminating internal weld points and reducing the number of potential leak paths. This construction ensures pressure boundary integrity under the cyclic loading typical of DP service.
Common applications include: differential pressure transmitter isolation and calibration, flow measurement installations, and level measurement systems where zero calibration under process conditions is required.
✓ Integrates isolation and vent in one block, fewer connections, reduced leak risk, faster maintenance
Technical Specifications
- Pressure Rating
6,000 PSI | 10,000 PSI
- Models
MOD. 300 (Threaded, without vents) | MOD. 302 (Threaded, double vent) | MOD. 305 (Flanged, without vents) | MOD. 306 (Flanged, double vent) | MOD. 315 / 316 / 317 (Flanged, without vents) | MOD. 322 ("H" Type, without vents)
- Connection Types
Flanged | Threaded (NPT) | F/F
- Connection Size
1/2" NPT-F | 1/4" NPT-F
- Centre Line
54×41.3 mm | 33×41.3 mm (instrument fixing centres)
- Materials
Stainless Steel 316/316L, Duplex, Monel, Hastelloy and other exotic alloys, NACE MR0175/ISO 15156 compliant for sour service
- Seal Options
PTFE | Graphite
- Mounting
Direct | Remote
- Venting
Without vents | Double vent 1/4" NPT-F
Key Features
Two Isolation + One Equalization
High-Integrity Construction
"H" Type Design Available
Double Vent Option
Where 3 Valves Manifolds Excel
3 valves manifolds are the ideal choice for:
Differential pressure transmitter isolation on flow, level, and pressure measurement loops
Zero calibration under process conditions by equalizing high and low sides without instrument removal
DP instruments on flanged or threaded process connections in Oil & Gas, Power Generation, and Chemical plants
Installations requiring independent venting of both high and low sides before maintenance assemblies
Need a different configuration?
Explore our 2 Valves manifolds for static pressure instruments, or 4–5 Valves manifolds for applications requiring full isolation, dual venting, and dual equalization.
2 Valves Manifolds
One isolation valve and one vent valve, compact solution for static pressure instrument isolation and safe depressurizationExplore
4–5 Valves Manifolds
The most comprehensive solution for differential pressure instruments, full isolation, dual venting, and single or dual equalization in one blockExplore
Distribution Manifolds & Drain Collectors
Single-body blocks for centralized distribution or collection of process fluid across multiple instrument linesExplore
