Re: [MW:13479] 3LPE pipe for direct pushing for the minor crossings

On Sun, 15 Jan 2012 06:19:14 +0530 wrote
>

Hi Lakshman,

below answers:-

(1)3LPE coated line pipe are preferentially used in HDD and Open Cut crossings where the ground
conditions are preferable i.e. where Stiff Clay is found.
FBE coatings are more susceptible tomechanical damage than 3LPE, I don't think there is a code
stipulating such requirements, if you are aware please inform.

Rock Jacket mechanical protection shall not be used over LPE to eliminate risk of snagging
during Pullback. ( I guess a geotech survey would havee been carried out so please refer same
and Client design specifications, intent is to suggest Do not believe above blankantly)

(2)Alternate option is to use Duallayer FBE Pipe (abrasion resistant layer).

(3)No Idea, i will ask experts (if the happen to be around) and post.

Regards
Manpreet Singh

Dear Friends,

I am having 3LPE coated pipes Dia of 45".

Now I have to use the pipes for special situations in a
cross country pipe line – especially for minor crossings like minor canal,
minor village road, river bund, local encroachments etc…

For critical crossings HDD is under process(above 600Mtr in
length), for major crossings cased crossings are in process(for above 100Mtr in
length) and for less than 50 mtr in length for above situations loading from
the top is negligible and pipe thickness will take the load pressure.

Now the query is…

1.
Is 3LPE pipe can be used for direct Jack pushing, if
yes, is there any codal reference supporting for this clause?

2.
What is the alternate option for outer coating for
direct pushing the pipe for short lengths and codal reference for the same?

3.
Is there any alternate method to overcome for the
situation of special crossings except cased crossings(because of cost matter in
cased crossings)?

Thanks
and Regards................?

Lakshman Kumar.B|Manager|Lanco Infratech Limited
Plot No 1255 |Sanjeevani chowk |Mahanadi vihar |Cuttack 753004
Phone : + 91
671 2445033 | Mobile : +91 9937286851 |www.lancogroup.com
Go Green|The future
will thank you

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