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.

Line Stopping

Home / Services / Line Stopping

Live Line Isolation Without Shutdown

WellFab’s Line Stopping provides engineered live pipeline isolation so repairs, tie-ins, valve replacements, and modifications can be done without shutting down the rest of the system. This method creates a temporary isolation point similar to a shut-off valve using industry-proven techniques and equipment.

WellFab's 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

These systems allow isolation of pressurized pipelines without interrupting service or causing product loss.

Typical Applications

Typical applications include:

• Pipeline segment repair, rerouting, or decommissioning

• Mid-line defect repair
• Installation of bypass lines
• Isolation for pressure vessel or manifold work

WellFab’s line stopping services maintain continuous operation of your system while delivering safe, controlled isolation and efficient project execution.

Types of Line Stops

Single Line Stop:

One isolation point is installed to stop or redirect flow in a specific section of a pipeline. Suitable for basic repairs, valve replacements, and branch connections.

Dual Line Stop:

Two stops installed in series create a fully isolated section between them. This method provides a pressure-free zone that can be drained and worked on safely, and may include a bleed/vent connection for added verification and safety.

Frequently Asked Questions

01
02
03
04

What We Do

Our mechanical services are comprehensive and engineered to meet the demands of today’s critical infrastructure projects. We design, fabricate, install, test, and maintain mechanical systems that keep facilities running safely and efficiently. Mechanical contractors like us are responsible for the complete lifecycle of systems — from initial planning to long-term maintenance, ensuring functionality, compliance, and reliability every step of the way.