7/25/2019 Installation of Dry Welding Habitat

1/2

Installation of Dry Welding Habitat to repair corroded casing

1) Prepare operational equipment:

1.1 Purpose prebuilt parts of dry habitat

1.2 hain hoists! for lifting parts of dry habitat in to position! lo"er do"n

1.# $race tubular for temporary holding! and restrain the installed dry habitat

1.% Di&ing support

1.' (n&ironmental control equipment! such as pump for de"atering and air supply!

lighting

1. Welding equipment *+,-W or /-W)

1.0 Weld inspection equipment

1. (quipment to remo&e marine gro"th and grit blast

2) $y di&er! using high3pressure "ater 4etting to clean the marine gro"th at the casing near

"ater surface and under "ater surface

#) 5ift and install bottom section of dry habitat

#.1 5ifting t"o parts of bottom section of dry habitat by chain hoists! bring in to

position

#.2 While temporary holding abo&e "ater surface! chec6 the fi7ing of preinstall side

"all and bottom "all that the neoprene seal properly installed in the "all soc6et

#.# $ring t"o parts of dry habitat to connect together! tightening the bolts along

&ertical side "all and bottom "all longitudinal 4oint to seal for "ater tight.

#.% hec6 the fi7ing of preinstall inflatable neoprene *t"o pieces of half ring shape)!

into to the soc6et around the 83'9 inch casing! and t"o pieces of I3shape

neoprene in bet"een the ends of half ring inflatable neoprene! that they are

properly installed in the soc6et.

#.' se the chain hoists to slo"ly lo"er do"n the connected bottom section dry

habitat

%) 5ift and install second section of dry habitat

%.1 5ifting t"o parts of second section of dry habitat by chain hoist! bring in to

position on top of the bottom section

%.2 hec6 the fi7ing of preinstall circumferential and &ertical side "all that theneoprene seal properly installed in the soc6et

%.# onnect the t"o parts of side "all by tightening the bolts along &ertical

longitudinal 4oint to seal for "ater tight.

%.% onnect the circumferential seal 4oint bet"een bottom and second section

together by tightening the bolts along circumferential 4oint

%.' se the chain hoists to slo"ly lo"er do"n the connected dry habitat to the pre3

determined le&el

') 5ift and install third section of dry habitat by repeat the sequence as per number %. *the

third section is optional in case of require to co&er the repair location9le&el)

7/25/2019 Installation of Dry Welding Habitat

2/2

) When the connected dry habitat has lo"er do"n to the pre3determined le&el! set all the

hanger chain hoist loc6! install and tie bracing to pre&ent lateral mo&ement of dry habitat

0) Inflate the inflatable neoprene at bottom casing seal 4oint to "ater tight around the casing

) De"atering "ater out from the inner habitat and dry inside the habitat

Dry "elding inside the dry "elding habitat

1) -fter the dry "elding habitat properly installed!

2) 5o"er do"n the fresh air duct in to the dry habitat to supply fresh air

#) $ring do"n "elding equipment and transfer the repair cre" inside dry habitat

%) lean the corroded surface of the casing *by grit blasting ) in preparation for "elding

half shell pipes

') Dry "eld *by +,-W or /-W) the half shell pipes along the require length to reinforce

the casing) Perform "elding inspection

7) When completed! remo&e the dry habitat by re&erse the installation sequence.