I. DN2600 Applicable Connection Methods

Socket-and-spigot Sealed Connection (Recommended for Large Diameters)

- Structural Design: The elbow has a socket and a spigot at each end. The spigot is equipped with a circular O-ring retaining groove (with a built-in corrosion-resistant rubber ring), and the socket has a stopper bar insertion opening.

- Leak Prevention Mechanism:

- O-ring dual-stage seal: The rubber ring is pre-compressed to achieve a low-pressure seal; under high pressure, the medium pressure pushes the rubber ring further to seal the seal.

- Stopper Bar Lock: Insert a PTFE stopper bar (12-20mm wide) to prevent the spigot from retreating. Applicable temperature ≥ 20°C (preheating is required for low temperatures).

- Installation Tips:

- Mark the spigot for insertion depth (depth = spigot length - end gap). After aligning the axis, slowly push in with a hand chain hoist.

- Use zinc/calcium stearate as a lubricant. Avoid applying to the bottom of the O-ring groove to prevent slippage.

Repair Methods After a Leak:

Baoshuo elbow repair clamps are customizable for pipe repairs in any diameter and length, including DN2600. They are made of high-strength carbon steel, with custom stainless steel options (304, 316, and 316L). The sealing rubber is EPDM, and custom options include fluororubber, silicone rubber, and NBR. They can be repaired under water and pressure without shutting off the flow.

2. Flange-Type Mechanical Connection

   - Structural Components:

   - Flanges are welded to each end of the elbow and bolted to the pipe flange.

   - Triangular support frames and bases are added to resist bending moments due to large pipe diameters.

   - Enhanced Leakage Prevention:

   - Gridded Rubber Seal: Layered pressure-relief rubber rings are used, resulting in a tighter seal as pressure increases.

   - Anti-Backlash Design: The V-groove seal creates reverse friction under high pressure, preventing bolts from loosening (such as the locking screws in zero-leakage elbows).

   Repair Methods After a Leak:

   Baoshuo Flange Repair Clamp, a pipe repair clamp, is customizable in any diameter and length, and can wrap around flanges of any size for repair. Made of high-strength carbon steel, stainless steel (304, 316, 316L) is also available. The sealing rubber is EPDM, fluororubber, silicone rubber, and NBR. Repairs can be performed under water and pressure without shutting off the water supply.

3. Threaded Lock Connection

   - Tapered Thread + Sealing Ring Dual Seal:

   - The elbow socket is machined with a tapered internal thread, with a sealing ring base at the root; the spigot is machined with a matching tapered external thread.

   - An elastic sealing ring (material selected based on the corrosion resistance of the medium) is inserted first. When tightened, the threads compress the sealing ring to form a double barrier.

   - Advantages: Removable and reusable, resistant to thermal expansion and contraction.

   🧿II. Key Technical Measures for Leak Prevention

   Multiple Sealing Structures

   - Low/High Pressure Staged Seal:

   - Low-pressure area: V-shaped packing or O-ring pre-tightening.

   - High-pressure area: Medium pressure activates the sealing ring for secondary expansion (e.g., a pointed convex sealing ring).

   - Water-absorbing expansion layer: A water-absorbing resin layer is lined inside the connection sleeve. In the event of a leak, it expands to fill the gap and guides the liquid into the groove of the leaking unit for temporary storage.

   Thermal Deformation Compensation Design

   - Clamp Assembly + Return Spring:

   - Slide rails and sliders are installed on the side walls of the connecting sleeve. The return spring allows the pipe to expand and contract axially (±10mm) via the return spring, preventing thermal stress cracking.

   - Free Rotation of the Flexible Elbow:

   - A steel ball annular groove structure (lower semicircular groove + upper semicircular groove) enables 360° rotation, compensating for installation deviations.

   Reinforcement and Support System

   - Anti-Tipping Bracket:

   - A base + triangular support frame (with reinforcing ribs at the bottom) distributes elbow torque.

   - Lifting Aid:

   - Welded fixing blocks are installed on the elbow, and the hook is secured with ropes and spring clamps to prevent damage to the interface caused by handling vibration.

   🧿III. Summary and Recommendations

   - Preferred Solution: Socket-and-spigot sealing connection (O-ring + retaining strip), suitable for large-diameter, low-pressure applications up to DN2600, balancing efficiency and sealing. High-pressure applications: Flange-type mechanical connection with anti-backlash seal and triangular support base. Leakage emergency response: Pre-installed water-absorbing expansion layer + pressure sensor monitoring, and a two-piece patch (Baoshuo Half Joint) are available. Key construction requirements: Axis alignment error ≤ 2°, and a 1.5x pressure test performed 48 hours after installation. The above design systematically addresses the risk of leakage in DN2600 fiberglass reinforced plastic elbows while also adapting to thermal deformation and external impact. The actual selection should be optimized based on the media pressure, temperature, and on-site support conditions.