Instrument Union
What are Instrument Unions?
Instrument unions are two-piece fittings used to securely join two tubes or pipes in high-precision fluid systems. These fittings allow for easy disconnection and reassembly without disturbing the overall pipeline, making them ideal for instrumentation, analytical, and control systems.
Asiad Steel Industries is a reputed supplier and exporter of instrument unions known for leak-proof performance, pressure handling, and resistance to vibration or thermal expansion. Our unions are manufactured from high-grade materials and conform to international quality norms.
Key Features
- Leak-Tight Connections – Ensures zero leakage in gas or fluid instrumentation lines.
- Reusability – Designed for multiple assembly/disassembly cycles without wear.
- Easy Maintenance – No need to disturb existing setups during servicing.
- Material Versatility – Available in SS 304, SS 316, brass, and alloy options.
- Precision Machined – Ensures tight tolerances and consistent sealing surface.
Specifications
Mechanical Properties
Chemical Composition
Equivalent Grades
Weight Chart
Specifications
| Parameter | Details |
|---|---|
| Size Range | 1/8″ to 2″ OD |
| Thread Types | NPT, BSPT, BSP, UNF |
| Pressure Rating | Up to 6000 PSI |
| Materials | SS 304, SS 316, Brass, Monel, Hastelloy |
| Standards | ASTM, ASME, DIN, ISO |
| Property | Typical Value |
|---|---|
| Tensile Strength | 515 – 750 MPa |
| Yield Strength | 200 – 450 MPa |
| Hardness | 120 – 250 HB |
| Working Temp | -50°C to +400°C |
| Element | Composition (%) |
|---|---|
| Chromium (Cr) | 18.0 – 20.0 |
| Nickel (Ni) | 8.0 – 10.5 |
| Carbon (C) | ≤ 0.08 |
| Manganese (Mn) | ≤ 2.0 |
| Silicon (Si) | ≤ 1.0 |
| Iron (Fe) | Balance |
| Standard | Equivalent Grade |
|---|---|
| ASTM | A182 F304 / F316 |
| DIN | 1.4301 / 1.4401 |
| JIS | SUS 304 / SUS 316 |
| EN | X5CrNi18-10 / X2CrNiMo17-12-2 |
| Size (Inch) | Material | Weight per 100 pcs (kg) |
|---|---|---|
| 1/4″ | SS 316 | 4.8 |
| 1/2″ | SS 316 | 8.2 |
| 3/4″ | SS 316 | 12.6 |
| 1″ | SS 316 | 16.9 |
Applications of Instrument Unions
Construction &
Infrastructure
Automotive & Heavy
Equipment
Manufacturing &
Fabrication
Medical & Laboratory
Equipment
Electrical &
Electronics Assembly
Oil, Gas & Petrochemical
Installations
Do you have questions?
Are your unions suitable for high-vibration applications?
Yes, our unions are vibration-resistant and suitable for demanding installations like offshore rigs and mobile equipment.
Do you offer unions in exotic alloys?
Absolutely. We supply unions in Monel, Inconel, Hastelloy, and Duplex upon request.
Can unions be reused after disassembly?
Yes, provided they are not physically damaged or excessively worn, they can be reused.
Are ferrules and nuts included with each union?
We offer both complete union assemblies (body + ferrules + nuts) and components individually.
