PG Packing Glands — Conax Technologies Compression Fittings
Conax Technologies PG packing glands from PG2 to PG9 — NPT sizes, compatible tube ODs, sealant options, and pressure ratings for probe assemblies.
PG Packing Glands
We supply the full range of Conax Technologies PG-series packing glands for use in sample probe assemblies, thermocouple installations, and other sealed instrumentation penetrations. The PG gland provides a reliable, adjustable, pressure-tight seal around tubes, rods, or wires passing through a pressure boundary.
For a comprehensive technical overview of how PG glands work, sealant selection, torque specifications, and engineering considerations, see our detailed guide: Conax Technologies PG Packing Glands.
Product Range
Complete PG-Series Specifications
| Model | NPT Thread | Max Tube OD | Common Tube ODs | Max Pressure (Teflon, 70 degF) | Body Length | Hex Size |
| PG2 | 1/4" NPT | 0.188" | 1/8" | 10,000 psi | 1.75" | 9/16" |
| PG3 | 3/8" NPT | 0.250" | 1/4" | 10,000 psi | 2.00" | 3/4" |
| PG4 | 3/4" NPT | 0.500" | 1/4", 3/8", 1/2" | 10,000 psi | 2.50" | 1-1/8" |
| PG5 | 1" NPT | 0.625" | 1/2", 5/8" | 10,000 psi | 3.00" | 1-3/8" |
| PG6 | 1-1/4" NPT | 0.750" | 5/8", 3/4" | 7,500 psi | 3.50" | 1-5/8" |
| PG7 | 1-1/2" NPT | 1.000" | 3/4", 1" | 5,000 psi | 4.00" | 2" |
| PG8 | 2" NPT | 1.250" | 1", 1-1/4" | 4,000 psi | 4.50" | 2-1/2" |
| PG9 | 2-1/2" NPT | 1.500" | 1-1/4", 1-1/2" | 3,000 psi | 5.25" | 3" |
Tube OD to Gland Size Cross-Reference
| Tube OD | Minimum PG Size | Recommended PG Size | NPT Thread |
| 1/8" (0.125") | PG2 | PG2 | 1/4" NPT |
| 1/4" (0.250") | PG3 | PG3 or PG4 | 3/8" or 3/4" NPT |
| 3/8" (0.375") | PG4 | PG4 | 3/4" NPT |
| 1/2" (0.500") | PG4 | PG4 or PG5 | 3/4" or 1" NPT |
| 5/8" (0.625") | PG5 | PG5 or PG6 | 1" or 1-1/4" NPT |
| 3/4" (0.750") | PG6 | PG6 or PG7 | 1-1/4" or 1-1/2" NPT |
| 1" (1.000") | PG7 | PG7 or PG8 | 1-1/2" or 2" NPT |
Sealant Options
| Sealant | Max Temperature | Chemical Resistance | Designation |
| Teflon (PTFE) | 500 degF (260 degC) | Excellent — most chemicals | Standard / "T" |
| PEEK | 600 degF (315 degC) | Excellent — superior high-temp | "K" suffix |
| Grafoil | 1,000 degF (538 degC) | Excellent in non-oxidizing | "G" suffix |
Replacement sealant element kits are available for all models and sealant types. See our technical guide for detailed sealant selection criteria and torque specifications.
Body Materials
| Material | Availability | Typical Application |
| 303 SS | Standard (all models) | General industrial service |
| 316 SS | Special order | Marine, moderate chloride environments |
| 316 SS (NACE MR0175) | Special order | Sour gas service with H2S |
| Monel 400 | Special order | HF acid, severe chloride service |
| Hastelloy C-276 | Special order | Aggressive chemical processing |
Accessories
- Sealant replacement kits: Pre-packaged sealant elements sized for each PG model and tube OD
- Adapter flanges: Convert NPT gland connection to ANSI 150#, 300#, 600# flanges
- Extension nipples: Increase the standoff distance between the process connection and the gland body
- Weldolets / threadolets: Matching process connections for each NPT gland size
- Stop collars: Set-screw retaining collars for the probe tube
- Retaining chains: Safety restraint chains for probe ejection prevention
How to Order
To specify a PG packing gland, provide:
1. Tube OD to be sealed
2. Process connection NPT size (or specify "match to tube OD" and we will recommend)
3. Sealant type: Teflon, PEEK, or Grafoil
4. Body material: 303 SS standard or specify alternate
5. Operating pressure and temperature
6. Applicable codes: NACE MR0175 compliance if required
For custom configurations, multi-tube glands, or non-standard tube sizes, contact our engineering team.