1. Ball Valve - Subsea Application April 2015
Technical Presentation
Ball Valve - Subsea Application April 2015

2. Application
Valves are used in industries like Refineries, Petrochemicals, Chemical Process Industries, etc. and their applications are to perform on-off, throttling, quick open / close(pressure relief/safety equipment), flow diversions of fluid in piping system
Type
Globe Valve
Gate Valve
Ball Valve

3. Type(Cont’)
Plug Valve
Diaphragm Valve
Pinch Valve

4. Type(Cont’) Applicable Codes Butterfly Valve Check Valve
API6D/6DSS(Specification for (Subsea) Pipeline Valves)
ASME B16.34(Valves — Flanged, Threaded, and Welding End)
API 6FA (Fire Test of Valves)
API 598 (Valve Inspection and Testing)
ISO 5210(Gear Box Design)
ISO 5208 (Seat Leakage Rate)
All Applicable ASME/MSS codes for end design(flanged/butt welded)

5. Details Derived from below Codes:
API6D/6DSS
Valve Types
Design(design code, calculations and construction)
Materials
Welding Requirements QC
Testing and procedure
Coating,Marking,Shipment and Documentation
ASME B16.34
Pressure-Temp Ratings
NPS and Marking
Materials Specification List
Dimension (Valve Body Thk)
Pressure Testing
Stress Calculation details

6. Valve Construction
End Design-Flanged End, Butt Welded End, Threaded End and Hub End
Bore Design – Full Bore or Reduced Bore
Ball Support – Trunnion Mounted or Floating ball
Shape – Spherical or Cylindrical
Number of Piece-One piece , Double piece and Three Piece – with welded connection or bolted connection
Hub Ended Design
Full Bore
Reduced Bore
Floating Ball type

7. Valve Construction(Cont’)
Trunnion mounted Ball type
Single Piece(Ent Entry – Threaded Connection)
3 Piece(Side Entry – Bolted Connection)

8. Valve Construction(Cont’)
To be designed for bending moment equal 85% of SMYS of the connecting line pipe and 1.5times design pressure
Seal to be designed to 1.5times hydrostatic pressure
Anti Blowout Stem Design
Anti Static Design
Length – Long Pattern or Short Pattern
Metal Seated or Elastomer Seated
Construction - Side Entry or Top Entry or End Entry
Ent Entry
[Anti Blowout Stem Design]

9. Valve Construction(Cont’)
Side Entry
Side entry ball valves are valves that assembled its ball from the side part.

10. Valve Construction(Cont’)
Top Entry
Top entry ball valves are valves that assembled its ball from top side part.

11. Valve Construction(Cont’)
Top Entry Vs Side Entry Valve
Side Entry
Top Entry
It is usually assembled in two pieces or three pieces body
It comprises a one single body
Usually side entry ball valves are made from forge metal.(more stronger)
Usually top entry ball valves are made from casting metal.
No need to have addition NDT test due to Minimized defect that causing from a casting valves.
Casting process introduce a lot of chance to have porous. So more additional NDT test required.
Easy to assemble and align trim component
Based on Vendor Experience
Fast delivery time from almost all vendors rather than a casting product that still needs some additional test.
Delayed Delivery due to casting process
Mostly used ball valve types and should be the default choice to specify a ball valve type in data sheet.
Top entry ball valves usually used at an application that require a minimal disassembly for in-line maintenances of its internal parts. This type is default choice where Frequent in-line maintenance is required

12. Valve Construction(Cont’)
Double Block and Bleed(DBB) Valve Assembly Unit and Integral DBB
DBB Assembly Unit
DBB – Integral Type
( Reason of DBB Valve Usage – It ensures complete isolation of instruments in the piping system)

13. Materials
Materials to be selected from ASME B16.34 from Material Specification List / Material Selection Report:
Carbon and Sulphur: .

14. Operation by Manual / Automatic
Materials (Cont’)
Charpy Test to be performed at 0 deg C Temp or as per specification ( if it is not provided in Spec , it can be considered from DNV).Hardness as per DNV(250 HV10).NACE requirement to be highlighted
Seal/gasket materials shall be resistant to amine based corrosion inhibitors. Seal material used in the valve shall have anti-explosion decompression property
Operation by Manual / Automatic
Lever Operated.400mm – 500 mm lever length is allowed
Hand wheel Gear Operated. Worm attached with hand wheel and Worm Gear attached with Valve Stem. Max 180N force to be applied at Hand wheel by Diver in Under Water
Automated Operated. Valve Operated by Machines(by servo motor or by ACTUATORS.) (Tensile stresses in drive-train components, including stem extensions, shall not exceed 67 % of SMYS when delivering the design thrust or torque)
Gearbox and Handwheel to be designed with safety factor of 2.

15. Applicable for both Onshore & Subsea Valves
Valve Testing
Applicable for both Onshore & Subsea Valves
Test Description
Code Requirement
Acceptance Criteria
Remarks
Torque Testing / Operational Test
API 6D / API 6DSS
(min 4 cycles required)
180N force to be applied at Handwheel to operate valve
Performed at maximum differential pressure
Hydrostatic Shell Test
(Test pressure – 1.5 or more times valve pressure rating
No leakage
Test Medium – Water. Duration – 2hrs
Hydrostatic Seat Test
(Test pressure – 1.1 or more times valve pressure rating
Leakage Rate – C (ISO-5208) for metal seated valves
Test Medium - Water. Duration – 10mins
Low -Pressure – Gas Seat Test
(Test Pressure - 0.5±0.007MPa)
Leakage Rate C for metal seated valves
Medium – Inert Gas / Air . Duration – 10min.

16. Applicable for both Onshore & Subsea Valves
Valve Testing (Cont’)
Applicable for both Onshore & Subsea Valves
Test Description
Code Requirement
Acceptance Criteria
Remarks
High – Pressure-Gas Seat Test
API 6D / API 6DSS
(Test pressure – 1.1 or more times valve pressure rating
Leakage Rate – C (ISO-5208) for metal seated valves
For gas service valve, Medium – air/nitrogen is to be used to justify the leakage rate. This is not Mandatory test.
Cavity – Relief Test
1.33 times valve pressure rating
Rejection if cavity pressure is not released before reaching pressure which shall be less than 1.33 times valve pressure rating.
Cathodic protection continuity test
API 6DSS
Measured resistance shall not exceed 10 Ω
Continuity shall be measured using a DC power source, not exceeding 12 V

17. Applicable for both Onshore & Subsea Valves
Valve Testing (Cont’)
Applicable for both Onshore & Subsea Valves
Test Description
Code Requirement
Acceptance Criteria
Remarks
Drive Train Strength Test(Gear box/Actuator)
API 6D/API6DSS
(2 times breakaway torque)
No Deformation Observed
Test Torque shall be applied with obturator(ball) blocked for a minimum time of 1min.
Cycle Testing
Not Required by API Codes
( May be Client Requirement).500 cycles
Rejection if the valve does not pass Hydrostatic Shell Test and Low -Pressure – Gas Seat Test
Once cycle test finished Hydrostatic Shell Test and Low -Pressure – Gas Seat Test to be repeated.
Vacuum Testing
( May be Client Requirement).This test is applicable for Valves
Used in Cryogenic Process.
Rejection if vacuum is not maintained.
The valve bone shall be evacuated to a pressure of 1.0 milli bar (absolute). The bone shall be isolated and the vacuum pressure shall be monitored for 1 hours

18. Applicable only for Subsea Valves
Valve Testing (Cont’)
Applicable only for Subsea Valves
Test Description
Code Requirement
Acceptance Criteria
Remarks
Hyperbaric Test
API 6D/API6DSS
(1.1 times Water Column Pressure of offshore installation site)
No Leakage
It is mainly performed to ensure the integrity of seal/gasket around stem area.

19. Valve Testing (Cont’)
Leakage Rate Details as per ISO 5208:

20. Valve Testing Procedures
Hydrostatic Shell Test: Water is pressurized at 1.5 times pressure rating from both Ends and Ball kept open. No Leakage is Allowed.
Vacuum Test is reverse of above test in which vacuum(1 mbar) is developed by suction process.
Hydrostatic Seat Test: Water is pressurized at 1.1 times pressure rating from both Ends and Ball kept Closed. Leak is observed from drain vent. Leakage Rate C is Allowed.
The same procedure is followed for low & high-pressure-gas-seat test.

21. Valve Testing Procedures (Cont’)
Localized End Cap
Stem
Cavity-Relief Test: Water is pressurized continuously up to a pressure at which seat releases the applied pressure. The applied pressure shall not exceed 1.33 times of pressure rating.
Hyperbaric Test: Water is pressurized from localized end-cap mounted at stem area at 1.1 times water column pressure of installation site. No leakage is allowed.

22. Inspection at Forged / Casting items and Weldment
Forged plate/parts to be 100% UT/RT inspected
Casting parts to be 100% RT inspected
If wall thk is ≥25mm, then RT to be supplemented by UT.
(General Note: UT needs expert operator to interpret results and Crack not found by RT can be found by UT.RT preferred for Volumetric imperfection Detection and UT preferred for Planar imperfection Detection [Height x Length]). .

23. Inspection at Forged / Casting items and Weldment(Cont’)
RT has been insisted over UT for welded area inspection by Our Inspection Team for DPE Project. But Valve Supplier supported UT due to the below reason ( Look at below figures)
Welding Procedure Qualification as per ASME Section IX is general requirement.

24. Sample Detailed Cross Sectional Drawing and Data Sheet
Sample Drawing _12_900-rev.3
Sample Valve Data sheet - DP RC Rev1_Datasheets for DBB Valves

25. THANK YOU