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Re: [MW:22116] Re: Buckling on floating roof




Dear Mr. Kumar,

When you weld the deck plates, you have installed number of temporary leg supports. After completion of the erection, you have removed all the legs except permanent legs. Just imagine the plates resting on few supports in order to more. 

So wherever we have no supports you will have the waviness.

Any how final decision is with the contractor and the owner. Even if you change the deck, you will encounter the same in the new.


வாà®´்க வளமுடன் என்à®±ுà®®் நலமுடன்

LOVE EVER HURT NEVER

Muthusamy.S

à®…à®®ீரகம் 





On 14 October 2014 20:24, Kumar <sk7920541@gmail.com> wrote:
Dear All,
Noted your suggestions. but the settlement readings are well within
the limits and none of them crossed 50mm..also the waviness is
scattered around the deck surface, some of them are above the legs &
others are far away as well. in this situation, it cant be deemed as
due to un-even settlement. this could be more due to improper
distortion arresting, welding in low ambient temperature etc.. any
how, Owner is proposing to find remedial measures or even may ask  to
change the deck! but according to the standards since it is silent
about this, there is no violation as such. appreciating for responses
if any.
Thanks in advance,
Kumar.
On 10/12/14, G Neethipathi <neethipathi@gmail.com> wrote:
> Dear Kumar,
>
> As per Mr.Muthusamy suggestion, you can record the deviations and to be
> submitted to Client for Review.
>
> Monitor and inspect for any abnormalities during Roof Floating movement and
> if it is normal we can Leave this issue and no need for carrying any repair
> or rectification works.
>
>
>
> *Thanks/regards,*
> *Neethipathi-G*
>
> *Contact numbers:*
> *+ 974- 66170687 (Qatar)*
> *+ 91- 8344044517 (India)*
>
> On Sun, Oct 12, 2014 at 9:50 AM, Kumar <sk7920541@gmail.com> wrote:
>
>> Dear Mr.Neethipathi,
>> Thanks much for your responses. the waviness are localised in the 72
>> mtr. dia deck in many spots ( having  length- 200 mm, width 150 mm).
>> the upper side of the wave is maximum of 47 mm & lower side of the
>> wave is 88mm with respect to the horizontal. this is a single deck
>> design. I have referred Appendix C of 650 but nothing seen about
>> waviness, buckling of Decks.
>> Thanks in advance,
>> Kumar.
>> On 10/11/14, G Neethipathi <neethipathi@gmail.com> wrote:
>> > Dear Mr. Kumar,
>> >
>> > What is  the area  and depth of buckling ? Minimum and Maximum
>> > measured??
>> >
>> > Your tank is with Single deck or double deck Floating roof??
>> > refer API-650,Annes-C for guidance.
>> > r
>> >
>> > *Thanks/regards,*
>> > *Neethipathi-G*
>> >
>> > *Contact numbers:*
>> > *+ 974- 66170687 (Qatar)*
>> > *+ 91- 8344044517 (India)*
>> >
>> > On Sat, Oct 11, 2014 at 11:25 AM, Kumar <sk7920541@gmail.com> wrote:
>> >
>> >> Hai,
>> >> Pls. note the material of construction is A 283 Gr.C. (also attaching
>> >> 2 more snaps for reference).
>> >> Regards,
>> >> Kumar
>> >> On 10/11/14, Kumar <sk7920541@gmail.com> wrote:
>> >> > Dear All,
>> >> > For a storage tank as per API 650 construction (dia- 72 mtr, height-
>> >> > 22 mtr), the external floating roof have found with some buckling &
>> >> > waviness  which is more noticable after the hydrotest. since the
>> >> > roof
>> >> > is resting on the fixed legs in the bottom plate, this might be due
>> >> > to
>> >> > the settlement of foundation during hydrotest. anyhow, sub-con is
>> >> > declining to rectify this as there is no criteria in 650 for
>> >> > floating
>> >> > roof. Kindly share your views(few snaps attached)
>> >> > Regards,
>> >> > Kumar.
>> >> >
>> >>
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