S 342-134

 (2)  
Let the resin partially dry until it is sticky.

 S 342-135

 (3)  
Press the duct ends together by aligning the installation
 checkmarks.

 S 342-136

 (4)  
Apply a thin, smooth layer of resin to the joint area a minimum of 2 inches wider than the duct joint.

 S 342-137

 (5)  
Apply resin to one side of the fiberglass cloth.

 S 342-138

 (6)  
Wind the fiberglass cloth around the duct joint a minimum of two times.

 NOTE: Make sure the resin on the fiberglass cloth is in contact
____
 with the duct.

 S 342-139
 (7)  
Put a plastic sheet on the fiberglass cloth and press lightly with a squeegee or with your hand. Make the fiberglass cloth smooth from the center to the edges of the cloth to remove any bubbles or any wrinkles and to remove unwanted resin.

 S 342-140

 (8)  
Let the resin cure for 24 hours at room temperature.

 F.
Put the Airplane Back to Its Usual Condition

 S 412-141
 (1)  
If insulation was removed from the duct joint, install new
 insulation.

 S 412-142

 (2)  
Replace the panels or other airplane structure removed to gain access to the duct joint.

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 TASK 21-23-01-302-143
 6. Duct End Repair - Polyurethane Foam Duct (Fig. 202)
________________________________________
 A. General
 (1)  
This procedure gives instructions for the repair of the end of a polyurethane foam air conditioning duct. This procedure is done if the lining that covers the polyurethane foam at the duct end is damaged and the polyurethane foam is exposed.

 (2)  
This procedure may be required when doing the repair of a taped duct joint.

 B.
Consumable Materials

 (1)  
Fiberglass cloth - minimum 0.007 inch (MIL-C-9084 Type VIII) -commercially available

 (2)  
Plastic sheet - polyethylene or vinyl - commercially available

 (3)  
Resin for repair of fiberglass duct - R109A Hetron 92 Polyester

 (4)  
Solvent - Butyl carbitol (alternative to B01011, Series 91) -commercially available (AMM 20-30-91/201)

 (5)  
Solvent - B01011, Series 91 - commercially available (AMM 20-30-91/201)

 (6)  
Wiping cloth, lint-free - commercially available

 (7)  
Squeegee - commercially available

 C.
References

 (1)  
AMM 36-00-00/201, Pneumatic - General

 D.
Prepare for the Repair

 S 862-144
 (1)  Release the pressure from the pneumatic system (AMM 36-00-00/201).
 NOTE: This will make sure that there is no airflow in the ducts
____
 when you do the repair.

 S 862-145
 (2)  
On the bleed air control module on the pilots' overhead panel, P5, the pack control switches in the OFF position.

 S 012-147

 (3)  
Remove the applicable ceiling, sidewall, or floor panels to gain access to the damaged air conditioning duct.

 S 012-148

 (4)  
If insulation is installed on the duct joints, remove the insulation.

 (5)  
Do these steps to prepare the damaged area of the duct.

 S 342-149
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MAINTENANCE MANUAL

 WARNING: DO NOT GET SOLVENTS IN YOUR MOUTH, OR YOUR EYES, OR ON
_______ YOUR SKIN. DO NOT BREATHE THE FUMES FROM THE SOLVENTS. SOLVENTS ARE HAZARDOUS MATERIALS. SOLVENTS MAY BE FLAMMABLE OR HARMFUL TO THE ENVIRONMENT. REFER TO PRODUCT MATERIAL SAFETY DATA SHEETS (MSDS) AND LOCAL REQUIREMENTS FOR PROPER HANDLING PROCEDURES.
　
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