Guidelines the DNV waygummiforeningen.no/.../020_JonHuseGuidelinestheDNVway.pdf · Guidelines the DNV way ... Guideline => Recommended Practice (RP) Where to find: ... Soft seals

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Guidelines the DNV way - for safe service elastomers in oil & gas

2012-05-15

Jon Huse 2012-05-15

Guidelines the DNV way

– for safe service elastomers in oil & gas



2012-05-15

Guidelines the DNV way – for safe service elastomers

Content:

What is a DNV-guideline?

Examples of DNV-guidelines - Qualification of soft seals - Arctic materials - Performance assessment of soft seals

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Blow Out Preventer

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Guidelines

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What is a DNV-Guideline? Developed through Joint Industry Projects (JIP)

Based on industry needs

In collaboration with industry

Need for standardisation

Guideline => Recommended Practice (RP)

Where to find: www.dnv.com or google “dnv codes”

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http://www.dnv.com/



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Guideline for qualification of soft seals

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Soft seals in the oilfield – Introduction

Elastomer and polymer materials are critical parts of equipment used to explore, produce and process oil and gas onshore, offshore and subsea

These applications are challenging for elastomer and polymer materials

New exploration is in deeper waters, reservoirs at higher temperatures and pressures, and in addition older fields are expected to last longer between equipment overhauls

Typical oilfield challenges may include:

Temperatures from - 30 oC to + 200 oC, vacuum to 1000 bar, pH 2 to 14, H2S, CO2, sulphur, amines, caustic, acids, treatment chemicals

Mechanical abuse is common and high pressures can cause “rapid gas decompression”

There is no universal elastomer to deal with all these conditions

Solution to selecting the right elastomer is through understanding the oilfield and the capabilities/limitations of available elastomers

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Challenges with elastomers and polymers Leaks are one of the main reasons for downtime of equipment

Elastomer or polymer seals are considered to be a major contributor to all leaks

Long term effects on elastomers and polymers are not well known

The industry offers limited standards to qualify new materials or sealing components

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JIP - Guideline for qualification of soft seals - Partners

Bel Valves

FMC Technologies

Petrobras

Seadrill

Seawell Oil Tools

Statoil

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Technology Qualification

DNV’s definition of Technology Qualification:

The process of providing the evidence that the technology will function reliably

within specific limits

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Qualification of soft seals based on technology qualification

Define accurately the design specification and qualification basis - Seal geometry - Seal material (elastomer properties) - Service conditions (including high pressure/high temperature (HPHT), chemical environment,

cyclic service conditions) - Failure modes for the soft seal - Design life

Establish if the technology is new and in need of full qualification

Establish relevant acceptance criteria before any testing

Test sealing system using relevant test methodology that mimick actual service conditions

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Technology Qualification of soft seal systems – Overview

FE-analysis



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Guideline for qualification of soft seals – includes also:

Recommendations on screening and qualification testing - Material testing

- Seal design testing

How to handle field experience Failure mechanisms

Material selection and applications Reference to relevant standards for screening and qualification testing Special conditions

Recommendation on FEA Change management Production QA/QC

…

Guideline is available upon request.

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Arctic Materials Guideline

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Arctic Materials Guideline Result of KMB lead by SINTEF with partners.

Objective:

To establish criteria and solutions for safe and cost-effective application of materials for hydrocarbon exploration and production in arctic regions.

2008 – 2012

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Arctic Materials - Partners Aker

Bredero Shaw

DNV

Eni

GE Oil and gas

NTNU

SINTEF

Statoil

Technip

Total

Trelleborg Offshore

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JFE Steel Corp, Japan

Nippon Steel, Japan

Scana

Bruck Forgings

Norwegian Research Council

http://www.sintef.no/home/

http://www.jfe-steel.co.jp/en/index.html

http://www.scana.no/



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Arctic Materials Guideline - objective Provide recommendations for a systematic approach to material selection

and qualification for applications in arctic.

1. General

2. Steel section

3. Polymer section

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What is Arctic?

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http://geology.com/world/arctic-ocean-bathymetry-map.shtml



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Oilfield Elastomer Applications Seals – topside and subsea

Thermal insulation – risers, pipes and subsea equipment

Corrosion protection – risers and pipes

Passive fire protection

Flexible joints

Elastomeric bearings

Hoses, pipes, cables, bellows, gaskets…

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Elastomers in arctic – considerations Low temperature physical properties

Glass transition

Low temperature crystallization

Impact resistance

Thermal contraction

Temperature variations and cyclic loads

Temperature gradients and structural loads

Low temperature adhesion

Ice accretion

Ice abrasion

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Arctic Materials Guideline Basis in existing codes for each application:

- Thermal insulation (e.g ISO/DIS 12736) - Seals (e.g ISO 10423, NORSOK M710) - Liners and sheaths - Passive Fire protection - Other elastomer applications - Corrosion protective coatings (e.g NORSOK M-501, NACE SP0108) - Composite applications (e.g DNV-OS-C501)

Codes are compared against the specific considerations relevant for arctic conditions and recommendations are given.

Although the codes often do not exclude the use of the code in arctic they are written based on the experience from more benign climates and have also only been used in benign climates.

Recommendations based on test results generated in project. Results TBA.

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Performance Assessment of Soft Seals

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© Oceaneering



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Performance Assessment of Soft Seals - Background

Subsea equipment is build for long no-touch times, but even so the equipment is pulled for refurbishment at intervals

During refurbishment all exposed seals are routinely changed

Replaced seals are routinely thrown away

Currently no routines for evaluation of replaced seals

No feedback loop to ensure that information about the state of the replaced seals ever reaches the product owners

Current practice does not exploit any of the learnings possible when replacing soft seals during refurbishment

Important knowledge and experience from refurbishments is lost due to lack of routines in collecting this information

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Documented field experience – how to obtain that? Evaluation of seals during refurbishment

would create essential documentation of field experience (both positive and negative)

Soft seals are qualified using a limited number of international standards, mostly written to cover production fluid exposure. Other media exposure environments are not well covered by international standards.

We know a lot how seals perform in the lab, but less about service performance

Seals may look bad and have swelled severely, but still function. This is not captured.

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Guideline: Performance Assessment of Soft Seals Industry need:

A DNV-RP on performance assessment of soft seals for subsea production and process systems and associated tools which will provide standardized documentation of field experience that is currently not available.

Testing of replaced soft seals will document state of seal after actual service

Standardized test protocol will ensure all replaced seals will obtain documented field experience

Documented field experience will provide added confidence in sealing solutions

Documented field experience will increase quality and reduce leakage in sealing systems

Testing of replaced seals will provide the link between laboratory testing and actual use in service

Basis for development of analytical tools, especially with regards to lifetime predictions

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JIP - Performance assessment of soft seals Q2 2012 – Q2 2013

Objective is to establish test methodology for refurbishments: - How to perform assessment – in workshop and

in lab - What to examine for and test - What service conditions and seal performance

data to capture - How to correlate with qualification data

Methodology will be tried out on participant’s equipment: - Christmas tree under refurbishment - Downhole equipment TBD

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JIP - Performance assessment of soft seals - participants

- Aker

- BP

- Eni

- James Walker

- Statoil - …

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http://www.jameswalker.biz/



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Safeguarding life, property and the environment

www.dnv.com

Thank you!

Documents

Guidelines the DNV waygummiforeningen.no/.../020_JonHuseGuidelinestheDNVway.pdf · Guidelines the DNV way ... Guideline => Recommended Practice (RP) Where to find: ... Soft seals