What is line stopping?

Line stopping is a controlled method of temporarily isolating a section of an active pipeline without shutting down the entire system. A specially engineered stop head is inserted through a hot tap, creating a secure, temporary block so repairs, tie-ins, or modifications can be completed safely.

Why would I need a line stop?

Line stopping allows you to perform work on a live system without draining, depressurizing, or disrupting service. It is the ideal solution for buildings, plants, or district-energy networks where shutdowns are not allowed or would be too costly.

Can a line stop be done without shutting down the system?

Yes. Line stopping is specifically designed for zero-downtime isolation. All work is performed while the system remains live and operational.

Can a bypass be installed during line stopping?

Yes. When continuous flow is required, WellFab can coordinate a temporary bypass around the isolated section to help maintain service while the repair, tie-in, valve replacement, or modification is completed.

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Line Stopping

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HOT TAPPING SERVICE

Live Pipeline Isolation Without Full System Shutdown

WellFab provides engineered line stopping solutions that allow repairs, tie-ins, valve replacements, and system modifications to be completed without shutting down the entire piping system.

Using proven hot tapping, line stopping, bypass, and isolation methods, WellFab creates controlled temporary isolation points on live pipelines so critical work can be completed safely, efficiently, and with minimal disruption to building operations, production, or service continuity.

Why Use Line Stopping?

Line stopping is ideal when shutdowns are difficult, costly, or not acceptable. It allows a section of pipe to be isolated while the rest of the system remains in operation.

This method can help:

✓ Maintain service continuity during critical work
✓ Eliminate large-scale drain-down and refill requirements
✓ Reduce restart and recommissioning risks
✓ Minimize operational and occupant disruption
✓ Shorten project schedules and outage windows
✓ Create isolation where permanent valves do not exist

Line Stopping Capabilities

Mechanical Line Stop

Range: DN20 (¾″) – DN610 (24″) and tailored sizes
Standards: ASME & DIN compliance
Operating Pressure: up to 360 PSI
Temperature: up to 520 °F
Compatible with virtually any pipe material
Bypass capability included

Bag (Inflatable) Line Stop

Range: DN20 (¾″) – DN2438 (96″) and tailored sizes
Standards: ASME & DIN compliance
Operating Pressure: up to 500 PSI
Temperature: up to 1350 °F
Compatible with virtually any pipe material
Bypass capability included

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Common Uses for Line Stopping

WellFab line stopping services are used when shutdowns are difficult, costly, or operationally unacceptable.

Typical applications include:

• Valve replacement without full system outage
• New tie-ins and branch connections
• Pipeline rerouting and modifications
• Mid-line repair and defect remediation
• Temporary bypass installation
• Isolation for pressure vessel or manifold work
• Heating, cooling, and utility system upgrades
• District energy and mechanical room modifications
• Emergency intervention on active systems
• Creating isolation where permanent valves do not exist

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Types of Line Stops

Single Line Stop:

A single temporary isolation point is installed to stop or redirect flow in a specific section of pipe. This is commonly used for basic repairs, valve replacements, branch connections, and controlled system modifications.

Dual Line Stop:

Two stopping points are installed to create an isolated section between them. This allows the section to be drained, depressurized, repaired, modified, or replaced while the rest of the system remains in service.

When continuous flow is required, a temporary bypass can also be installed to maintain service around the isolated section.

Built for Live-System Work

Every line stop requires planning, coordination, and controlled execution. WellFab reviews pressure, temperature, pipe material, access, flow direction, isolation requirements, bypass needs, and operational risk before work begins.

Our team supports each project with practical field planning, fitting installation, bypass coordination when required, pressure monitoring, leak checks, controlled reinstatement, and QA/QC documentation.