🧿1. Connection Method Selection and Procedures

Socket-and-socket Connection (Recommended for Large Diameters up to DN2800)

- Applicability: Suitable for locations with stable geology or where flexible settlement compensation is required. The process is mature for pipe diameters ≥300mm.

- Procedures:

Preparation: Clean the socket and spigot end faces. Check that the O-ring groove is intact. Mark the insertion depth on the spigot end (actual depth minus 4mm end play).

Sealing Ring Installation:

- Use a water-swellable rubber ring and insert it into the groove on the spigot end.

- Use a rounding tool to press the rubber ring for even tension. Apply zinc stearate lubricant to the surface (to prevent the lubricant from seeping into the groove bottom).

Repair Methods After a Leak:

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

2. Flange Connection (for frequent disassembly or connection)

   - Steps:

   Flange Treatment: Install EPDM gaskets on both sides of the flange. Tighten the bolts three times in diagonal order (the final torque value must be within ±5% of the design value).

   Corrosion Protection: Apply molybdenum disulfide anti-corrosion grease to the bolts. Wrap the flange outer edge with fluororubber sealing tape to isolate moisture.

   Wrapping Butt Joint (Suitable for on-site repairs or special-shaped pipes)

   - Steps: Grind the joint to a 45° groove → Apply epoxy resin adhesive → Alternately wrap with glass fiber mat/cloth (≥ 3 layers) → After curing, apply UV protective adhesive to the exterior.

   Repair Methods After a Leak:

   Baoshuo tee repair clamp, a pipe repair clamp, is customizable in any diameter and length, and can wrap around flanges of any size. 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.

🧿II. Special Leakage Prevention Measures

Structural Leakage Prevention Design

- Double Seal System:

- First: Water-swelling rubber ring (self-expands to fill gaps in the event of leakage);

- Second: A water-absorbing and swelling layer (such as bentonite tape) embedded in the connecting sleeve expands 20 times its volume upon absorbing water, sealing micro-gaps.

- Leakage Sensing Unit:

- A pressure-sensing curved plate is installed inside the tee socket. Leaking liquid pushes against the curved plate, triggering a sensor alarm. The liquid is also temporarily stored in a recess (capacity ≥ 5L).

Thermal Deformation Compensation

- Flexible Constraint:

- The clamping assembly (e.g., connecting claw + return spring) allows for ±10mm axial displacement of the pipe to prevent thermal stress cracking.

- The fixed bracket is ≥ 2 pipe diameters away from the tee, using a sliding support.

Interface Strengthening

- End Face Treatment: Sandblasting roughening (Ra ≥ 50μm) before socketing to improve adhesive adhesion;

- Low-Temperature Protection: When ambient temperature is <5°C, preheat the stop bar to above 20°C to restore flexibility.

🧿 III. Key Quality Control Points

Alignment Check: Laser alignment test, axis deviation ≤ 1mm/m;

Pressure Test:

- Pressurize in stages to 1.5 times the working pressure, maintain pressure for 30 minutes, and a pressure drop of ≤1% is considered acceptable;

Leak Scanning:

- Infrared thermal imaging detects abnormal temperature patterns at the interface (temperature differences > 0.5°C indicate potential leaks).

🧿 IV. Conclusions and Recommendations

For DN2800 tee connections, the preferred solution is a socket-and-socket + double seal + stop bar locking solution, equipped with a leak detection unit. In areas at risk of subsidence, a return spring clamp assembly should be added to compensate for displacement. During construction, the rubber ring installation accuracy (no distortion) and pressure test holding time are strictly controlled.