Instrument Fittings
What are Instrument Fittings?
Instrument fittings are precision-engineered components designed to ensure leak-free connections in small-diameter piping and tubing systems, often used for gas, liquid, and instrumentation signal lines. These fittings are critical in high-pressure and high-purity applications such as oil & gas instrumentation, laboratories, pharmaceuticals, and chemical plants.
Asiad Steel Industries is a reputed manufacturer, supplier, and exporter of precision instrument fittings, engineered to provide leak-proof, reliable, and accurate connections in instrumentation, hydraulic, and pneumatic systems.
Key Features
Leak-Proof
Jointing
Durable
Construction
Easy Installation
& Removal
Wide
Compatibility
Corrosion
Resistant
Specifications
| Specification Category | Parameter / Feature | Details / Options |
|---|---|---|
| Size Range | Tube OD Sizes | 1/16″ to 2″ (2 mm to 50 mm) |
| Thread Sizes | 1/16″ to 2″ (NPT, BSPT, BSPP, ISO) | |
| Custom Sizes | Available on request | |
| Types of Fittings | Male Connectors | Tube OD × Male Thread (NPT/BSP/ISO) |
| Female Connectors | Tube OD × Female Thread (NPT/BSP/ISO) | |
| Unions & Tees | Straight Union, Bulkhead Union, Union Elbow, Union Tee, Reducing Tee, Cross Union | |
| Ferrules | Single Ferrule & Double Ferrule, Front Ferrule, Back Ferrule | |
| Material Options | Stainless Steel | SS 304, SS 304L, SS 316, SS 316L (per ASTM A276 / A479) |
| Other Options | Brass, Duplex 2205, Super Duplex 2507, Monel 400, Inconel 625/825, Hastelloy C22/C276 | |
| Standards | International | ASTM, ASME, DIN, ISO, BS |
| Testing Compliance | NACE MR0175/ISO 15156, MSS-SP-99 | |
| Pressure Ratings | Standard | Up to 6000 psi (400 bar) |
| High-Pressure Versions | Up to 10,000 psi (690 bar) | |
| Temperature Range | With PTFE Ferrules | −196 °C to +200 °C |
| With Metal Ferrules | Up to +650 °C | |
| Seal / Ferrule Options | Ferrule Types | Stainless Steel Ferrules, Brass, PTFE, PFA, Graphite |
| Leak-Proof Seal | Zero leakage under vibration & pressure cycles | |
| Surface Finish | Internal Bore | Precision-machined, smooth for minimal pressure drop |
| External Finish | Bright annealed, passivated, polished | |
| Testing & Certification | Tests Conducted | Hydrostatic Test, Pneumatic Test, Helium Leak Detection, Vibration Test, PMI Test |
| Certifications | ISO 9001, CE, PED 2014/68/EU, EN 10204 3.1/3.2 | |
| Applications | Industries | Instrumentation, Hydraulic & Pneumatic Systems, Oil & Gas, Refineries, Power Plants, Petrochemical, Process Control |
Dimensions
| Metric Range | Dimension in mm | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Part | T | P | L1 | M | C | D | F | G | H | N |
| N0 | mmo/d | Length | Body | Nut | Body | |||||
| 4mMC2 | 4 | 1/8′ | 31.35 | 9.53 | 16.67 | 14.29 | 12 | 12 | 24.21 | 10.72 |
| 4mMC4 | 4 | 1/4′ | 35.72 | 14.29 | 16.67 | 14.29 | 14 | 12 | 29.37 | 15.88 |
| 6mMC2 | 6 | 1/8′ | 33.34 | 9.53 | 18.26 | 15.88 | 14 | 14 | 25.40 | 11.11 |
| 6mMC4 | 6 | 1/4′ | 33.34 | 14.29 | 18.26 | 15.88 | 14 | 14 | 30.16 | 12.70 |
| 6mMC6 | 6 | 3/8′ | 38.89 | 14.29 | 18.26 | 15.88 | 19 | 14 | 30.96 | 13.49 |
| 6mMG8 | 6 | 1/2′ | 44.45 | 19.05 | 18.26 | 15.88 | 22 | 14 | 36.51 | 15.88 |
| 8mMC2 | 8 | 1/8′ | 34.53 | 9.53 | 19.05 | 16.67 | 14 | 17 | 26.59 | 11.51 |
| 8mM04 | 8 | 1/4′ | 39.29 | 14.29 | 19.05 | 16.67 | 14 | 17 | 31.35 | 13.10 |
| 10mM02 | 10 | 1/8′ | 35.72 | 9.53 | 19.84 | 17.46 | 17 | 19 | 27.78 | 11.91 |
| 10mMC4 | 10 | 1/4′ | 40.48 | 14.29 | 19.84 | 17.46 | 17 | 19 | 32.54 | 13.49 |
| 10mMC6 | 10 | 3/8′ | 40.48 | 14.29 | 19.84 | 17.46 | 19 | 19 | 32.54 | 13.49 |
| 10mMC8 | 10 | 1/2′ | 46.04 | 19.05 | 19.84 | 17.46 | 22 | 19 | 38.10 | 15.88 |
| 10mMC12 | 10 | 3/4′ | 46.83 | 19.05 | 19.84 | 17.46 | 27 | 19 | 38.89 | 15.08 |
| 12mMC4 | 12 | 1/4′ | 43.66 | 14.29 | 22.23 | 23.02 | 22 | 22 | 33.34 | 11.11 |
| 12mMC6 | 12 | 3/8′ | 43.66 | 14.29 | 22.23 | 23.02 | 22 | 22 | 33.34 | 11.11 |
| 12mMC8 | 12 | 1/2′ | 48.42 | 19.05 | 22.23 | 23.02 | 22 | 22 | 38.10 | 12.70 |
| 12mMC12 | 12 | 3/4′ | 49.21 | 19.05 | 22.23 | 23.02 | 27 | 22 | 38.89 | 13.49 |
| 12mMG16 | 12 | 1′ | 54.76 | 25.40 | 22.23 | 23.02 | 32 | 22 | 44.45 | 15.88 |
Mechanical Properties
| Property | Value | Unit / Standard |
|---|---|---|
| Tensile Strength | 520 – 750 | MPa |
| Yield Strength | 200 – 350 | MPa |
| Hardness | ≤ 215 | HB (Brinell) |
| Elongation | ≥ 35 | % |
| Density | 7.9 | g/cm³ |
| Impact Toughness | ≥ 80 | J (Charpy) |
| Modulus of Elasticity (E) | ~200 | GPa |
| Fatigue Strength | 280 – 340 | MPa |
| Corrosion Resistance | Excellent (SS 316/316L for instrumentation) | – |
| Thermal Conductivity | 14 – 16 | W/m·K |
| Coefficient of Thermal Expansion | 16 – 17 ×10⁻⁶ | /°C |
| Yield Ratio (YS/UTS) | 0.38 – 0.55 | – |
| Poisson’s Ratio | 0.27 – 0.30 | – |
| Brinell Hardness Range | 160 – 215 | HB |
| Surface Finish | Ra ≤ 0.4 | μm (Precision grade) |
| Operating Temperature Range | -75 to 425 | °C |
| Pressure Rating | Up to 6000 | psi (depending on size & material) |
Chemical Composition
| Element | SS 304 (%) | SS 304L (%) | SS 316 (%) | SS 316L (%) |
|---|---|---|---|---|
| Chromium (Cr) | 18.0 – 20.0 | 18.0 – 20.0 | 16.0 – 18.0 | 16.0 – 18.0 |
| Nickel (Ni) | 8.0 – 10.5 | 8.0 – 12.0 | 10.0 – 14.0 | 10.0 – 14.0 |
| Carbon (C) | ≤ 0.08 | ≤ 0.03 | ≤ 0.08 | ≤ 0.03 |
| Manganese (Mn) | ≤ 2.00 | ≤ 2.00 | ≤ 2.00 | ≤ 2.00 |
| Silicon (Si) | ≤ 1.00 | ≤ 1.00 | ≤ 1.00 | ≤ 1.00 |
| Phosphorus (P) | ≤ 0.045 | ≤ 0.045 | ≤ 0.045 | ≤ 0.045 |
| Sulfur (S) | ≤ 0.030 | ≤ 0.030 | ≤ 0.030 | ≤ 0.030 |
| Iron (Fe) | Balance | Balance | Balance | Balance |
| Molybdenum (Mo) | — | — | 2.0 – 3.0 | 2.0 – 3.0 |
Do you have questions?
What’s the difference between single and double ferrule fittings?
What pressure ratings do instrument fittings typically support?
Do you offer instrumentation valves with these fittings?
Can these fittings be used in high-purity applications?
