Tore Aarsland Chairman of the Editorial Revision Committee / Senior Design Engineer @ C6 Technologies

10-Jan-13

1. The well barrier philosophy of the standard is harmonised to NORSOK D-010. The use of the term tertiary well control is therefore discontinued.

2. The requirements of the final element of the secondary barrier has been expanded to reflect today's expectations and understanding.

3. External references has been updated and the number of them reduced.

4. Test requirements for pressure control equipment is further specified.

5. Requirements for subsea operations, hose management, dropped objects and lifting operations are added.

6. Mandates independent 3rd party verification of new designs, products and solutions related to the final element of the secondary barrier.

7. The structure is revised to increase readability.

8. The inclusion of operational requirements have been reduced as these are not included in the scope of the standard. Some are, however, kept as they are found to be critical for a safe operation. These are never preceded by the verbal form shall.

1. Scope 2. Normative and informative references 3. Terms, definitions and abbreviations 4. General requirements 5. Well control 6. Snubbing 7. Coil tubing 8. Wireline

The scope of this NORSOK standard is to provide common functional requirements for well intervention equipment used on the Norwegian Continental Shelf across the different operators. Tools and equipment intended for deployment inside a well is not covered.

Well intervention is the deployment of tools and equipment in a completed well. An intervention string is normally used to lower and retrieve the tools. Alternatively, the string can constitute the tool itself. Expected well pressure = reservoir pressure - minimum well fluid gradient + kill margin

Wireline is intervention using a continuous string without any internal bore. Coil tubing is intervention using a continuous string with an internal bore. Snubbing is intervention using jointed pipe

Equipment under the scope of this standard will by default fall into at least one of the following categories and shall satisfy the requirements of the corresponding standards: • Topside Pressure Control Equipment: ISO 10423 • Subsea Pressure Control Equipment: ISO 13628-7 • Temporarily Equipment: NORSOK Z-015 • Supporting Structures: NORSOK N-001

This standard is applicable for all well intervention equipment manufactured after the 1st of January 2014. All well intervention equipment shall comply to this revision no later than the 1st of January 2018.

All suppliers that design, manufacture or sell well intervention equipment shall have a quality management system based on ISO 9001 or equivalent. All new designs, products and solutions related to the final element of the secondary barrier, including the control of said device, shall be verified by an independent 3rd party.

Hose assemblies should be managed, inspected and replaced according to Guidelines for the management of flexible hose assemblies. These guidelines are published by Energy Institute in the UK.

Lifting equipment shall be designed according to NORSOK R-002. Lifting operations should be carried out in according to NORSOK R-003. Provisions shall be made for handling of BHAs in compliance with these lifting requirements.

Well intervention equipment shall be designed according to part 2 of Handbook – Best Practice – Dropped Object Management to reduce the risk of dropped objects. These are guidelines published by Samarbeid for Sikkerhet

• The required product specification level (PSL) of pressure control equipment is determined by annex A in ISO 10423.

• Rams and valves under the scope of this standard shall be tested to performance requirement 2 (PR2) according to annex F in ISO 10423.

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• BOPs and safety heads having an vertical through-bore dimension equal or greater than 7 1/16" shall be designed, manufactured and tested according to ISO 13533. This replaces the above requirement to test according to annex F in ISO 10423 for such equipment.

• Be able to shear the intervention string in use with less than 90% of the max hydraulic working pressure, demonstrated by a shear test according to ISO 13533 Annex C.2.3

• Independent HPU (not shared with the primary barrier)

• SIL 2 (same as for a drilling BOP)

• All connections forming the secondary barrier envelope shall have metal-to-metal seals

• Two control panels, one should be located in the control cabin

• HPU located in a non-hazardous area outside the wellhead area

• There shall be at least two independent technical measures to prohibit the accumulation of multiple strands of severed intervention string through the secondary well barrier. This requirement is not applicable for intervention strings without any compressive strength.

A snubbing operation on the Norwegian Continental Shelf will most often be rig assisted due to the requirement for a remotely operated pipe handling system. This standard does not intend to introduce additional requirements for permanently installed drilling equipment which is covered by NORSOK D-001.

The requirement for dual redundant stationary snub slips have been removed. This is not used in recent operations because the safety interlock system implemented on all rigs is sufficient to ensure the retention of the string.

The possibility of using old, conventional tongs has been removed. Tongs shall be remote operated.

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• Control of the primary well barrier from the cabin added

• Increased required rate of grease injection, from 0.25 l/min to 0.75 l/min.

• Updated requirements for speed and tension

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Wire size

Creep Speed

(outer diameter)

[m/min]

Full Speed

(inner diameter)

[m/min]

Max pull

(outer diameter)

[kg]

Acceleration

[m/s2]

< 3/16” ≤5 ≥150 ≥1 500 2

≥ 3/16"

≤ 7/32" ≤2 ≥80 ≥3 000 1

> 7/32” ≤0.5 ≥60 ≥5 000 0.5

• 9: Documentation

• Annex A: Data Sheet Snubbing Equipment

• Annex B: Safety Head Requirements

• Annex C: Snubbing and Coil Tubing Rig-Up

• Annex D: Wireline Rig-Up

• Provisions shall be made for handling all equipment and BHAs in compliance with lifting requirements

• 3rd party verification of new designs, products and solutions related to the final element of the secondary barrier

• Two control panels for the final element of the secondary barrier, one of the shall be installed in the control cabin