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Title: |
Piping and Valves |
Doc. No. |
L-001 |
Annex |
F |
VSK |
V405 |
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Project: NORSOK |
Company: |
Rev.Date: |
20.09.99 |
Rev: |
3 |
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ID |
DATE |
VSK. TEXTS |
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108 |
20.06.94 |
Trunnion mounted double seated ball valves: |
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The following valve sizes shall have grease fittings in the body for injection to the seat area: · 6"-8": 1 fitting per seat. |
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109 |
20.06.94 |
All valves: |
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All components not specified in the VDS shall have equivalent to or better corrosion resistance than the component they are coupled to. Asbestos containing material is not permitted. |
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15.12.97 |
Carbon steel valves and gearboxes shall as a minimum be primed according to NORSOK standard M-501; "Surface protection and protective coating". |
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20.09.99 |
Externally exposed components in austenitic stainless steel shall minimum be of type 316 (L) SS. |
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20.09.99 |
Fabrication welding of pressure retaining components and attachments welded onto those components shall be carried out according to NORSOK Standard M 601, "Welding and Inspection of Piping Systems". Welding of other valve components shall be carried out according to welding procedure specifications to ASME IX. |
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20.09.99 |
Assembly drawing of the valve shall be supplied with the bid, and shall at least show:
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20.09.99 |
All valves with graphite stem packing, desity of graphite to be 1.3 to 1.7 g/cm3. |
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20.09.99 |
For all valves with O-ring or lip-seal: |
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Back-up rings for O-rings or lip-seals When back-up rings are utilised due to design considerations the material shall be PEEK (polyetheretherketone) or PTFE (polytetrafluorethylene). |
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110 |
20.06.94 |
All valves exept check valves: |
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The stem or other sliding elements and plugs shall have a hardness and surface finish in order to avoid galling. |
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111 |
20.09.99 |
All valves of rating >= Class 600 for gas service applying elastomers: |
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Elastomer materials shall be able to resist rapid pressure reduction in gas service application. Supplier shall provide report verifying that all materials are suitable for gas application at the pressure rating listed in the VDS. Seal groove filling: In applications where rapid pressure reductions are likely to occur in gas containing systems, the degree of groove fill for O-rings and corresponding seal systems shall not be lower than 85% and not more than 90%. |
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112 |
20.06.94 |
Ball and gate valve: |
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The following valves shall be equipped with a drain plug in bottom of the valve body: · Floating ball valves > = 4" |
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113 |
20.06.94 |
Ball valves >= 4": |
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Valves shall have a stem lubrication fitting for lubrication of stem. |
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116 |
20.09.99 |
All Ball/Butterfly: |
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Valve shall have inherently antistatic or fitted with an antistatic device. An internally screwed stuffing box is not permitted. The gland packing and gland shall be compressed independently of the stem nut such that rotation of the stem shall not impart forces into the gland or gland packing. |
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20.09.99 |
All valves |
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ENP is only accepted used on stainless steel substrates to reduce friction, in cases were this problem can not be solved in an optimal manner by other solutions e.g.: material selection, hard facing or thermal spraying. ENP shall not be used in valves for sea water or other corrosive services. |
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155 |
25.11.94 |
All valves > = 2": |
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If drilled and tapped body connection are made (drain, vent, test conn. etc.). they shall be fitted with forged plugs of anti blow out design with hexagon heads. The plugs shall be made to ANSI B 16.14 using same basic material as the body. For austentic materials, the plugs shall be coated to prevent galling. For all carbon steel valves, the body plug shall be of duplex material type UNS S31803. Body tappings shall conform to ANSI B 16.34 or as specified in the valve standard. |