Extreme HPHT Projects - Impact of Material Performance Review

16/01/2017 - Oil&Gas

A next generation of analysis to validate consistent production and early communication between operator and Vallourec lead to the project’s success
An HPHT project in the Gulf of Mexico for a Major US operator presented 18000psi and 300degF downhole conditions. The initial discussions on the project were held 3 years prior to project spud. The tie-back was going to be made of 3 strings due to well constraints. One string required a new dimension and grade combination of pipe. Two other strings were 'off the shelf' designs.

To satisfy the operator's requirement for a new pipe dimension, a study was conducted to validate the supply route. Also additional data was needed for validation of the pipe properties and repeatability of production.

Vallourec organized a mini-roll of the new pipe dimension, and 1000ft were produced. A dedicated Quality Plan was generated to support the intense mechanical testing regime required and generate pipe data. Working with the customer, the parties agreed upon the analysis method of results. The pipe was also provided for the connection tests due to the new design requested.

To ensure quality and performance Material Performance Reviews were conducted. Within 6 months the mini-roll was produced to the agreed commitments and quality plan. This included pipe mapping for sample taking, optimizing pipe usage, and ensuring enough pipe was available for connection testing.

The data was generated at the mill both in MTR and database format. The mechanical properties – yield, strength, UTS, hardness, toughness had a quality assurance analysis performed, assessing it against the material specification and the window of production statistical consistency.

Lessons Learned:

The validation process applied to the mechanical properties of the material used in the well. However the process was not limited to the pipe being simply within specification, but focused on being be within an acceptable statistical bell curve. Special attention was also given to the production route in terms of the capability to provide this dimension.

In summary, the project relied on a next generation of analysis to validate consistent production. The early communication between the operator and Vallourec lead to a clear understanding of expectations on which to build the project. It was also understood that depending on the method of analysis the results can be expected to vary, therefore the requirements need to be defined as per expectations.

The data capture from the mill was modified to a database format which allowed analysis to be performed quickly, and establish confidence on the reliability of supply.