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[MW:14166] Change in Manufacturer for Plate Requires MPQT in Line pipe

By Materials & Welding
Dear Experts,
 
         One of the Manufacturer initially rolled the line pipe (API 5L) for the line item x ( dia 44" x 16.9 mm) with Voset Alpine plates, for the same manufacturer conducted Manufacturer Procedure Qualification test (MPQT) and the result found satisfactory. As there was not enough quantity of plates to complete the line item Manufacturer informed the line item x will be rolled after procuring the plates. Mean time manufacturer rolled for other line items of the same P.O with different sizes. Manufacturer received the plates from Sumitomo instead of Voest alpine to complete the partially rolled line item x ( dia 44" x 16.9 mm). In this case whether manufacturer shall conduct MPQT once again for the Sumitomo Plates for the line item x ( dia 44" x 16.9 mm) or elsae we shall conduct test unit only instead of MPQT. Please clear my doubt.

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G.Murali krishnan

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Comments

Punit Dubey said…
Dear Murali

MPQT should be carried out with the change of manufacturing process of line pipe.
As supplier is changing the steel source/steel making and rolling practice (and hence the manufacturing process of steel which is a part of line pipe manufacturing process), hence MPQT should be repeated.
Also have a close look over line pipe specification you may also find some details over there.

Regards

Punit Dubey
9925150566
May 1, 2012 at 8:39 PM
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