Choke clearing of tubes in W5 Heat Exchanger and leak testing of W5 and W2 Heat exchanger tubes in SA Plant FACT - CD, during ATA 2020.

Choke clearing of tubes in W5 Heat Exchanger and leak testing of W5 and W2 Heat exchanger tubes in SA Plant FACT - CD, during ATA 2020.

Arrangements for W5 Tube choke clearing: Collect required materials / Tools for the work from store and transport to work site. Make necessary site arrangements for the work. Open all manholes of W5 heat exchanger. Arrange required scaffolding. Cut open and remove the top cone of W5 HE along with associated outlet and bypass ducts (if necessary) to facilitate the choke clearing of tubes. After removing the cone the outlet duct and bypass duct shall be given temporary supports . The side (suitable side may be chosen depending upon the site conditions) of the shell along with baffle plate, any other ducts, valves etc. May be dismantled with the concurrence of Site engineer for ease of work for removing / cutting damaged tubes.

Cleaning of acid sludge between the tubes and tube sheets of W5:- Thorough cleaning of deposited acid sludge between the tubes and tube sheets using necessary tools to facilitate improvement of efficiency of heat exchange process.

Choke clearing of W5 Heat Exchanger Tubes:- Make necessary site arrangements including scaffolding for the work. Each blocked tube shall be cleared using suitable equipment.

Arrangements for Leak Testing of W5 and W2 tubes.:- Transporting the required MS plates from stores /near by plant area, collection of scaffolding material etc. and providing the required scaffolding at site / site arrangements. Marking / cutting the new MS pates [8mm thick, approximate OD 2000 mm ] for providing slip plates (1800 mm dia) and grinding the inside / outside plate edges properly. Cutting and blinding the W5 inlet and outlet duct, 1800 mm dia and full welding in order have a leak free joint. Closing of W2 outlet vent dummy, 800 NB, with proper gasket in order to have a leak free joint. Fabrication and erection / hooking up of air lines with necessary accessories like hose connection / valves etc. at desired point for leak testing of W5 and W2 tubes. Provide required assistance for leak testing. Leak test the replaced tubes as per standards and instructions from competent authority. Any leaks detected shall be corrected as per site instructions.

Plugging the leaky tubes of W5 and W2 on both sides with suitable plugs and full welding as per instructions of Engineer-in-Charge .1 No= 2 plugs.

Full welding of cone and boxing up W5 and W2:- Removal of blinds from 1800 NB Duct for W5, and other dummies closed for W2, removal of hose connection / testing arrangements and full weld the duct joint after edge preparation / grinding etc. in order to have leak free joint, removal of scaffolding arrangements, scrap removal etc. Prepare the edges of W5 shell at cone area, cone, outlet duct and bypass ducts. Erect back the cone along with removed outlet duct and bypass duct. Full weld the cone, outlet duct and bypass duct after proper fit up. The ducts shall be erected back without any strain. Pad plates shall be provided at joints with full welding if required as per instructions from competent authority. After welding the cone and ducts erect back the dummies and man hole covers. Any other ducts, valves etc. that were removed from the site, shall be welded back once the work is over and shall be under the scope of the contractor's work. Any structural supports for ducts shall be provided. Clear the site after work and transport the scrap to scrapyard.

MUHAMMED M K

HASSAN MM

PAREETH V V

GOPINATHA PANICKER ENGINEERING CONTRACTOR

VIKRAMAN NAIR S