7/30/2019 52071279 Pickling Procedure

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DECREASING AND PICKLING PROCEDURE FOR C.S. PIPES

STEP 1 : DETERGENT BATH

Pipes and pipe spools shall be kept in soap bath for atleast 30 mins., later pipes

and pipe spools will be rinsed with water.Soap : NaOH

Testing and inspection by PH paper : 7 PH

STEP 2 : DEGREASING

Dipping in Trichloroethylene ( TCE ) chemical 15 mins, later clean with water

STEP 3 : PICKLIING

Pipes and pipe spools shall be kept in a diluted Hydrochloric acid ( HCL) for 2 to

3 Hours. HCL will be diluted to 5 10% concentration by using water.

STEP 4 : CLEANING

Pipes and pipe spools shall be thoroughly rinsed with water by water spray.

Ensure proper pickling and cleaning.

STEP 5 : NEUTRALISATION

Pipes and pipe spools shall be kept in Sodium hydroxide bath ( NaOH ) bath for

hour. NaOH will be diluted to 3% by using water.

STEP 6 : CLEANING

Pipes and pipe spools shall be thoroughly rinsed with water by water spray.

Ensure proper Neutralisation and cleaning.

STEP 7 : PASSIVATION

Pipes and pipe spools shall be kept in Passivation bath of Sodium Hexa Meta

Phosphate at 75C for 2 to 3 hours, later mob with clean cloth.

STEP 8 : DRYING

Dry with dry air / N2 gas and sealing the ends with card board.