Pipe Fittings
Hex Plug Pipe Fitting
Stark hex head plug for secure, leak-free sealing of unused female ports. Forged 316SS, high-pressure rated. Ideal for system maintenance, testing, and future expansion points. 24h quote!
Hex Head Plug Pipe Fitting: Secure Port Closure
Securely seal and isolate your unused system ports. The Stark Hex Head Plug is a high-integrity male-threaded fitting designed to provide a reliable, leak-free closure for female-threaded ports in valves, manifolds, and piping systems. Machined from a single piece of forged 316/316L stainless steel, it offers superior strength, corrosion resistance, and a robust hex head for easy, high-torque installation and removal.
✓ One-Piece Forged Body| ✓ High-Pressure Seal| ✓ Easy Installation & Removal
🔧 Configure Your Hex Plug in Seconds
Find your required plug by selecting the thread type and size.
1. Select Your Thread Type:
○ NPT (High-Pressure Process Standard)○ BSPT (R) (ISO Tapered - General Industrial)○ BSPP (G) (Parallel - Leak-Free Soft Seal)○ Metric / SAE (OEM & Hydraulic Specialty)
2. Select Your Thread Size
🔥 Most Popular Sizes (In Stock - Same Day Shipping)
1/4" NPT | 1/2" NPT | 3/4" NPT | 1" NPT |
SS-TPP-MN4 | SS-TPP-MN8 | SS-TPP-MN12 | SS-TPP-MN16 |
Part Number Format: [Material]-TPP-[Thread] (e.g., INC625-TPP-MN4)
(TPP = Hex Plug)
🛠 The Engineering Advantage
- Superior Strength with One-Piece Forging: Stark Hex Head Plugs feature a solid-body construction. Unlike plugs machined from standard bar stock, our hex head plugs are made from forged 316L stainless steel. This provides a superior grain structure that offers higher strength and resistance to cracking under high pressure and installation torque.
- Precision-Machined Threads for a Perfect Seal: Our NPT and BSPT tapered threads are machined to exacting ASME and ISO standards. This ensures perfect thread engagement and a secure, leak-free seal when properly installed with thread sealant, even in high-pressure gas applications.
- Heavy-Duty Hex for High-Torque Installation: The robust hexagonal head is designed for a secure, non-slip grip with standard wrenches, allowing for proper torque application to achieve a reliable seal. It also facilitates easy removal, even after long service periods.
- Guaranteed Material Integrity: Every Stark pipe fitting comes with full material traceability. We provide a Material Test Report (MTR) to EN 10204 3.1and PMI verification as standard, giving you absolute confidence in the material you are installing.
📈 Technical Specifications
Feature | Stark Standard Specification |
Body Material | Forged 316/316L Stainless Steel |
Thread Types | NPT, BSPT (R), BSPP (G), Metric / SAE |
Pressure Rating | Up to 10,000 PSI (689 bar), varies by size |
Compliance | MTR to EN 10204 3.1 & PMI Verified |
🎯 Why Choose a Stark Hex Plug? A Head-to-Head Comparison
Feature | Standard Commodity Plugs | The Stark Forged Hex Plug |
Construction | ⚠️ Often machined from bar stock (weaker) | ✅ One-Piece Forged Body (Superior Strength & Safety) |
Thread Quality | ⚠️ Inconsistent, prone to leaks | ✅ Precision-Machined & Gauged (Leak-Free Seal) |
Wrench Grip | ❌ Thin or poorly defined hex | ✅ Heavy-Duty Hex (High-Torque, Damage-Free Installation) |
Material Traceability | ❌ None | ✅ Full MTR + PMI Verification with Every Order |
📌 Targeted Application Support
- System Maintenance & Isolation: Securely cap off unused ports on valves and manifolds during maintenance or system shutdowns.
- Pressure Testing: Used as a reliable end-of-line seal for hydrostatic or pneumatic pressure testing of piping systems.
- Future Expansion Ports: Install on spare ports of a manifold or vessel to provide a secure, ready-to-use connection point for future system upgrades.
- OEM Equipment: Used by equipment manufacturers to seal auxiliary or optional ports on their products before shipping.
❓ Frequently Asked Questions (FAQ)
Q1: What is the main purpose of a hex head plug?
Its main purpose is to securely seal an unused female threaded port. It prevents leaks, keeps contaminants out of the system, and maintains system pressure integrity.
Q2: Do I need to use thread sealant (like PTFE tape) with this plug?
Yes. For all tapered thread types (NPT and BSPT), a high-quality thread sealant is required to fill the microscopic gaps in the threads and ensure a gas-tight, leak-free seal, especially under high pressure.
Q3: What is the difference between a hex head plug and a hollow hex plug?
A Hex Head Plug (this product) has a solid external hex head for installation with a standard wrench. A Hollow Hex Plug (or Allen plug) has an internal hex socket for installation with an Allen key, resulting in a flush or low-profile finish. The choice depends on your space constraints and tool availability.
Q4: Can I reuse this plug after it has been installed?
While it is physically possible, for critical or high-pressure applications, we strongly recommend using a new plug and fresh thread sealant for every installation. Reusing a tapered thread plug can compromise the integrity of the seal.
📦 Complete Size Chart
💬 Still Have Questions?
Our engineering team is ready to assist with technical selection, system design, or material recommendations.
🔒 Disclaimer
Swagelok® and Parker® are registered trademarks of their respective holders. Stark is not affiliated with, endorsed by, or sponsored by these companies. Part numbers and brand names are provided for cross-reference and compatibility purposes only.