Repair Coupling

This instruction has been prepared for the correct and safe installation of Repair couplings used for repairing leaks, cracks, and damages, as well as for joining pipes in potable water, wastewater, and industrial pipeline systems.

FOR REPAIR APPLICATIONS

1. Pre-Installation Preparation

• Correct Size Selection:
  Measure the pipe outer diameter (O.D.) using a caliper or circumference tape.
  Ensure that the sleeve size indicated on the label matches the pipe diameter.
• Surface Cleaning:
  Remove mud, rust, loose coatings, and deposits from the pipe surface using a wire brush.
  A clean and smooth surface is critical for proper sealing.

2. Installation Steps

2.1 Lubrication

• Apply soapy water or a suitable lubricant to the pipe surface and gasket.
  This ensures smooth positioning and prevents gasket folding during tightening.
• Warning:
  Do not use petroleum-based oils or grease, as they may damage the gasket.

2.2 Positioning the Sleeve

• Preparation:
  Fully loosen the nuts and open the sleeve.
  Wrap it around the damaged section of the pipe.
• Centering:
  Ensure the damaged area is centered within the sleeve body.
  The sleeve length should extend at least 50–100 mm beyond the damaged area on both sides.

2.3 Closing and Initial Tightening

• Bring the sleeve lugs (ears) together.
• Ensure the gasket sits properly and wraps evenly around the pipe.
• Insert the bolts and hand-tighten the nuts until snug.

2.4 Tightening Sequence

• Tighten bolts from the center outward in a crosswise pattern, gradually and evenly.

3. Final Check & Commissioning

• Waiting Time:
  After installation, wait 15–20 minutes and recheck bolt torque.
  The gasket may settle and reduce tension slightly.
• Pressure Test:
  Gradually pressurize the pipeline and check for leaks.
  If leakage occurs, do not overtighten—slightly loosen, reposition, and retighten.

FOR PIPE JOINING APPLICATIONS

1. Pre-Installation Preparation

• Product Verification:
  Check DN size and tolerance range to ensure compatibility with both pipe outer diameters.
• Pipe Cutting:
  Cut pipes square to the axis (90°).
  Uneven cuts may prevent proper sealing.
• Surface Cleaning:
  Clean pipe ends thoroughly (rust, dirt, coatings).
• Chamfering (If Required):
  Apply a ~30° chamfer to pipe ends to prevent gasket damage during insertion.

2. Positioning & Marking

• Insertion Depth Marking:
  Measure the sleeve body length and mark half-length on each pipe.
• Alignment:
  Ensure both pipes are aligned axially as much as possible.

3. Installation Steps

• Lubrication:
  Apply a silicone-based lubricant to gasket and pipe ends.
• Positioning:
  Slide the sleeve onto the first pipe.
  Bring the second pipe into position and center the sleeve over both pipe ends.
• Gap Check:
  Leave a 10–20 mm gap between pipe ends to allow for thermal expansion and settlement.

4. Tightening (Critical Step)

• Tighten bolts using an Allen key (or appropriate tool) in a crosswise pattern.
• Do not fully tighten one bolt at once—tighten gradually and evenly across all bolts.

5. Final Check & Testing

• Visual Inspection:
  Pressure plates on both sides must be parallel after tightening.
• Pressure Test:
  Perform a low-pressure leakage test before commissioning.
  Recheck bolts if necessary.

SAFETY NOTES

• Use protective gloves and safety footwear during installation.
• For large diameters, use pipe supports or blocks to prevent load on the sleeve.
• Ensure bolt coatings (Galvanized / Dacromet / etc.) are not damaged to maintain corrosion resistance.