Single-Flange Dismantling Joint

🔧 Single-Flange Transmission Joint – Technical Parameters

🧱 Single-Flange Transmission Joint – Materials Specification

🛠️ Single-Flange Transmission Joint – Installation Guide

✅ 1. Pre-Installation Preparation

• Inspect Components: Ensure that all parts (body, flange, bolts, gaskets) are complete and free from damage, rust, or debris.

• Check Compatibility: Confirm the joint size (DN), pressure rating, and flange standard match the pipeline specifications.

• Clean Connection Surfaces: Ensure the flange faces and pipeline ends are flat, clean, and free of oil, rust, or burrs.

🔧 2. Installation Procedure

Step 1: Positioning

• Insert the welded or socket end of the joint into the corresponding pipeline.

• Align the flange face of the joint with the pipeline flange.

Step 2: Gasket Placement

• Place a gasket (NBR, EPDM, or PTFE) between the flanges. Center the gasket precisely to avoid displacement during bolting.

Step 3: Bolt Installation

• Insert bolts through the flange holes and tighten the nuts gradually.

• Use a cross-tightening pattern (e.g., 12 o’clock → 6 o’clock → 3 o’clock → 9 o’clock) to ensure uniform pressure.

• Use a torque wrench to follow manufacturer-recommended torque values.

Step 4: Axial Adjustment

• Adjust the telescopic end of the joint to compensate for misalignment or expansion.

• Fix the axial length before final tightening of the locking bolts (if equipped).

Step 5: Final Check

• Verify that all bolts are evenly tightened and the gasket is properly seated.

• Ensure the joint is not under excessive bending, twisting, or pulling force.

⚠️ 3. Installation Precautions

• Do not use the joint to forcibly correct pipeline misalignment.

• Do not weld or cut any part of the joint after installation.

• Avoid over-tightening bolts to prevent deformation of the sealing surface.

• Install support brackets if the pipeline is long or heavy to reduce axial load.

🧪 4. Pressure Testing

• After installation, conduct a hydrostatic or pneumatic pressure test.

• Monitor for leaks at the flange face and around the gasket.

• Retighten bolts if necessary, following the cross-pattern sequence.

🧰 Single-Flange Transmission Joint – Maintenance Guide

🔍 1. Routine Maintenance (Monthly / Quarterly)

• Visual Inspection:

  • Check for surface corrosion, rust, or damage on the flange, bolts, and body.

  • Look for signs of leakage around the gasket area.

• Bolt Tightness Check:

  • Use a torque wrench to ensure all bolts maintain the proper torque.

  • Tighten bolts in a cross-pattern if loosening is detected.

• Gasket Observation:

  • If there is minor leakage, the gasket may be aged or misaligned. Plan for replacement.

🛠️ 2. Annual Maintenance Checklist

• Disassembly & Cleaning (if required):

  • Shut down the system and release pressure before removing the joint.

  • Clean internal surfaces to remove sediment, rust, or scale.

  • Inspect the sealing surface for scratches or wear. Smooth out minor defects with appropriate tools.

• Gasket Replacement:

  • Replace the gasket if hardened, cracked, or deformed.

  • Ensure the new gasket is compatible with the conveyed medium and temperature.

• Coating Inspection:

  • Check the internal and external anti-corrosion coating.

  • Touch-up epoxy or reapply paint if peeling or damage is found.

• Reassembly:

  • Reinstall the joint following the standard installation guide.

  • Conduct pressure testing before resuming operation.

🔒 3. Long-Term Reliability Measures

• Service Life Monitoring:

  • Maintain a logbook of installation date, material batch, and service condition.

  • Replace the joint if it exceeds the recommended service life (typically 8–15 years depending on medium and environment).

• Environmental Consideration:

  • For buried pipelines, inspect the joint chamber for flooding or water retention.

  • Ensure cathodic protection systems (if any) are functioning for underground metallic pipelines.

• Torque Recheck Frequency:

  • In high-pressure or high-vibration environments, recheck bolt torque every 3–6 months.

⚠️ 4. Replacement Criteria

• Severe corrosion on flanges or bolts

• Irrecoverable deformation of the joint body

• Persistent leakage despite re-tightening

• Gasket completely hardened, cracked, or melted