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?
Are your fittings compatible with Swagelok® or Parker® systems?
Do you offer instrumentation valves with these fittings?
Can these fittings be used in high-purity applications?
