Across nuclear facilities and refineries, maintenance teams face ongoing pressure to complete heat exchanger repairs rapidly, safely, and with full confidence in long‑term performance. Tube failures remain a persistent challenge, and the ability to quickly isolate a compromised tube—without damaging the tube sheet or introducing additional inspection complexity—is essential during critical outages.
Yet many traditional plugging approaches introduce uncertainty. Welded plugs and hydraulic expansion systems can increase schedule time, require specialized tooling, and offer little real‑time feedback during installation. Hammer‑driven pins and tapered plugs may produce inconsistent results and are prone to tube sheet damage.
In environments where predictability and repeatability matter most, plants are looking toward simpler, more controlled solutions.
Torque‑Based Plugging: A Different Approach
One method gaining significant traction is the torque‑style mechanical plug. Unlike alternatives that rely on force, heat, or hydraulic pressure, torque‑based plugs provide positive, measurable feedback throughout installation. This gives technicians a clear indication that the plug is fully seated and correctly engaged with the tube wall.
This is the engineering philosophy behind Torq N’ Seal® Heat Exchanger Tube Plugs, now widely used in nuclear stations, refineries, and petrochemical plants. Each plug’s design revolves around a simple concept: installers should feel and measure the exact moment a plug forms a proper mechanical seal.
Why Torque Feedback Matters
During outages—especially in radiologically controlled areas—maintenance crews depend on consistent behavior from every tool and component. Torq N’ Seal plugs provide that consistency through a smooth, progressive torque curve. As torque rises, the installer feels the expansion ferrule engage, press outward, and form a controlled metal‑to‑metal seal.
This predictable installation behavior offers several critical advantages:
- Consistency: Every plug responds the same way, regardless of operator or location.
- Verification: Torque values act as measurable, repeatable quality checks.
- Speed: Installations often take under 60 seconds, minimizing exposure time and critical path duration.
- Confidence: Teams can immediately confirm a proper seal—something not possible with welded or forced‑fit alternatives.
Technical Specifications That Support Performance
While Torq N’ Seal plugs are known for speed and simplicity, their technical performance makes them suitable for even the most demanding environments, including nuclear ASME Section III applications.
Key technical attributes include:
High‑Pressure Capability
- Permanent sealing up to 7,000 psi;
- Tested reliably up to 10,000 psi.
Size Range
- Standard solutions cover 0.250”–2.500” (6.35–63.50 mm) tube IDs.
- Custom diameters can be manufactured for specialty exchangers or unique degradation profiles.
Material Options
- Available in Brass, Carbon Steel, 304/316 Stainless Steel, Duplex, Inconel, Titanium, and additional exotic alloys.
- Ensures compatibility with seawater service, high‑temperature applications, and corrosion‑sensitive metallurgy.
Certification & Compliance
- Options available to meet:
- ASME Section III (nuclear)
- ASME B31.3, ASME PCC‑2, ASME Section VIII Div. 1
- ISO 9001
- CSA B51 and CSA Z662
Installation Requirements
- Installs with only a standard 3/8″ square‑drive torque wrench.
- No hydraulic pumps, pullers, welding rigs, or special training required.
Tube Sheet Protection
- Gradual, symmetrical expansion prevents thermal or mechanical shock.
- No damage to ligaments—unlike welding, explosive plugs, or hammered pins.
- Can be inserted at any depth to bypass internal tube sheet corrosion.
One‑Piece Design
- Eliminates secondary leak paths common in multi‑piece plugs.
- Wide serrated sealing zone ensures a reliable, uniform seat even with minimal tube preparation.
Built for Flexibility in Real‑World Conditions
Torq N’ Seal plugs are engineered for use in:
- Feedwater heaters
- Moisture separator reheaters
- Preheaters
- Condensers
- Coolers and fin‑fan exchangers
- Any tubed heat exchanger in refinery or power‑generation service
Their compact profile and drive‑capture tooling make them ideal for tight spaces near baffles, shells, or dividers—common problem areas in older exchangers.
A Fast, Simple, and Effective Upgrade for Outage Planning
For nuclear operators and refinery maintenance planners seeking a solution that minimizes risk and accelerates outage timelines, torque‑style plugs provide an efficient and verifiable alternative. Torq N’ Seal Heat Exchanger Tube Plugs combine predictable torque‑based installation with industry‑leading pressure performance—delivering the controlled, confident results technicians need during the moments that matter most.
Learn More
To request a sizing chart, technical data sheet, or engineering support for your next outage, visit www.torq-n-seal.com, email plugs@torq-n-seal.com, or call (201) 641‑2130.