API 579 Fitness for Service

[kEng1]

Can anybody help me interpreting Para 4.4.3.3.c.1 in API 579 codes? The specific sentence says &quot;If L < Lv, the midpoint of L should be located at tmm to establish a length for thickness averaging unless the location of tmm is within L/2 of the zone for thickness averaging&quot;

My query is:
How to determine the location of tmm in reference to the zone for thickness averaging?

Thanks.

 

[meca]

Wouldn't tmm be the point at which the &quot;Minimum Measured&quot; thickness was located? Then the area for thickness averaging is based upon the criteria in 579.

 

[kEng1]

Thank you for your reply.

I understand the location of tmm is fixed. However my specific question is the interpretation of the last sentence &quot;...the location of tmm is within L/2 of the zone for thickness averaging&quot;.

How can we determine whether the location of tmm is within L/2 of the zone for thickness averaging? As I understand the zone for thickness averaging (Lv) is a length, not a point where we can measure the distance to the tmm location.

Regards,
kEng1