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16 May 2014


    NEW RESEARCH VESSEL R/V "KRISTINE BONNEVIE" - MGG CONSIDERATIONS    

     Project description

UNIVERSITY OF BERGEN
Department of Earth Science
 Allé gt. 41, N-5007 Bergen, Norway 
             
0.1   DRAFT - request for comments - 25 April, 2017 OM OM -
VER. STATUS CHANGE DATE BY CKD APPD
Click to enlarge.

RV "Kristine Bonnevie", 23 November 2016. Click to enlarge.

This web page presents University of Bergen considerations related to Marine Geology & Geophysics (MGG) on the new research vessel "Kristine Bonnevie". Planning is done jointly with University of Tromsø, Department of Geology who is also involved in a broad range of MGG activities (mainly based on RV "Helmer Hansen").

  RV "Kristine Bonnevie" - Principal Particulars  
Length overall: 56.75 m
Length between perpendiculars: 48.55 m
Breadth: 12.50 m
Frame spacing: 0.55 m

1.  COMPRESSED AIR - HSE CONSIDERATIONS


Accident report: IAGC [International Association of Geophysical Contractors]: "Hi Pressure incident 2011"

2.  COMPRESSOR CAPACITY - REQUIREMENT


Who Conf. no. Survey type Desired pressure No. and type of airguns - volume Firing rate Equivalent flow rate
University of Bergen
Dpmt of Earth Science
1 Refraction 138 Bar (2000 psi)
  • 4 ea Bolt mod. 1500 airguns
  • Each airgun chamber volume 1200 inch3 = 19.66 liter1)
  • In total 4800 inch3 = 78.7 liter
Firing every 200 meter, with max ship speed 6 knots, gives firing rate of 200/(6*1852/3600)

= 65 s

(78.7 liter / 65 s) = 1.21 liter/s =
72.6 liter/min @ 138 Bar
2 Reflection 138 Bar (2000 psi)
  • 4 ea Bolt airguns with various chamber sizes
  • Total volume (typ.): 766 inch3 = 12.55 liter
Firing every 50 meter, at max speed 6 knots, giving shot interval of

50/(6*1852/3600) = 16.2 s

(12.55 liter / 16.2 s) = 0.77 liter/s =
46.5 liter/min @ 138 Bar
3 Reflection 138 Bar (2000 psi)
  • 4 ea Bolt airguns with various chamber sizes
  • Total volume (typ.): 766 inch3 = 12.55 liter
Firing every 25 meter, at max speed 6 knots, giving shot interval of 8.1 s 1.55 liter/s =
93.0 liter/min @ 138 Bar
University of Tromsø
Geology Dpmt
4 Reflection 200 Bar (2900 psi) 1 airgun, 30 inch3 volume = 0.492 liter 3 s shot interval (0.493 liter/3s) = 0.164 liter/s =
9.9 liter/min @ 200 Bar
5 Reflection 200 Bar (2900 psi) 1 airgun, 420 inch3 volume = 6.883 liter 41 s shot interval (6.883 liter/41s) = 0.168 liter/s =
10.1 liter/min @ 200 Bar

1) Conversion from cubic inch to liters - this online converter is used.

  • Cubic Feet per Minute = CFM = ft3/minute at actual conditions
  • Standard Cubic Feet per Minute = SCFM = ft3/minute at standard conditions (1 atm = 14.7 psi, 68°F = 20°C )

"Worst case" equivalent flow rate is thus 93 liter/min (3.284 cf/m) @ 138 Bar (2000 psi).

This is equivalent to 450 SCFM (where SCFM = Standard Cubic Feet per Minute = ft3/minute at standard conditions 1 atm = 14.7psi, 68°F).

3.  POWER AVAILABLE ON RV "KRISTINE BONNEVIE"


If practical, compressor should have electrical power.

There is 3-phase outlet, 380 V, 50 Hz, 125 A max, on shelter deck. The amount of power available is given by the following expression:

4.  RESERVED CONTAINER LOCATIONS


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R/V "KRISTINE BONNEVIE" - reserved locations for 10' containers.

4.1  Starboard side, Forecastle deck


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Container position Starboard side, facing bow. Click to enlarge.

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Container position Starboard side, facing stern. Click to enlarge.

IS IT POSSIBLE TO HAVE CONTAINER LONGER THEN 10 FEET ON STARBOARD SIDE?


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4.2  Port side, Forecastle deck


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Container position Port side, facing stern. Click to enlarge.

5.  COMPRESSOR SPECIFICATIONS - preliminary


  1. Capacity: 375 CFM at 2000 PSI (138 Bar).
  2. Compressor should be containerized.
  3. Container should include high pressure storage bottles, control valve and blow off silencer.
  4. Electrical or diesel powered (will be determined at later stage).
  5. Compressor can be monitored and operated remotely, from vessel instrument room.
  6. To be determined: Location of pressure sensor (for monitoring HP output pressure) and distribution of this sensor signal.
  7. IP interface to facilitate remote diagnostics and service

6.  COMPRESSOR MANUFACTURERES


List of manufacturers
Sauer compressor
LMF
Granzow AS
Seamap
Wärtsilä Hamworthy Seismic Compressors
Atlas Copco

6.1  Sauer compressor


Click to visit SAUER Compressor rental web page.

Click to visit SAUER Compressor rental web page.

6.2  LMF compressor


A request has been sent to LMF for a technical solution and a quotation regarding a mobile system for a compressor used for marine seismic operation. The main requirement is constrained by the capacity which should be at minimum 10.4 m3/min free air, corresponding of the current compressor on R/V Håkon Mosby.

The technical answer proposed by LMF is:

High Pressure Compound Compressor LMF 11sL/138-207 E60 Piston Compressor BS102-309 S21

A capacity of 11 m3/min (390 cfm) and a discharge pressure of 138 barg (2000 Psig) or 207 barg (3000 psig). [Using atmospheric pressure as reference is usually signified by a "g" for gauge after the pressure unit.]

LMF compressors

Overall compressor Unit Data:


Power consumption:main consumeraux. consumer
Screw/piston Compressor208 kW
Cylinder lubrication0,25 kW
Compressor control system approx.3,00 kW
Oil heater piston compressor1,00 kW

Voltage / frequency for auxiliary drives and control system suitable for 380 V/50 cps or 440 V/60 cps

Seawater inlet/outlet temperature max.35°C / 40°C
Seawater consumption approx.25 m3/h
Required freshwater inlet pressure2 bar g

Dimensions and Weights


Compressor unit dimensions (in m)
Length incl. sea/freshwater heat exchangers (plate type)approx. 2,8
Widthapprox. 2,3
Heightapprox. 1,7
Compressor unit weightapprox. 9,5 to
Control cabinet dimensions (in m)
Width0,8
Depth0,6
Height2,2
Control cabinet weight (in to)0,4 to

6.3  Granzow AS


6.4  Seamap


6.5  Wärtsilä Hamworthy Seismic Compressors


6.6  Atlas Copco


7.  CONTAINER FOR SEISMIC RECORDING


(For later consideration.)

8.  MAGNETOMETER WINCH FOUNDATION


(For later consideration.)

9.  MEETING WEEK 17/2017 - CLARIFICATION OF TECHNICAL ISSUES


Agenda

  1. Adherence to relevant standards?
    Should this delivery be in compliance with NORSOK Z-015 "Temporary equipment" (Rev. 4, September 2012) ?
    Which parts (if any) of the compressor / HP air system should be subject to inspection & approval by e.g. DNV?
    (To indicate risks associated with HP air, here is accident report issued by IAGC (International Association of Geophysical Contractors): "Hi Pressure incident 2011"
  2. Report from IMR regarding placement of 10 feet / 12 ton container compressor on board RV "Bonnevie".
  3. If and how lay-out of compressor container should be influenced (if possible) by its location on board. Could affect position of:
    • Operator interface.
    • Manifold for HP air distribution (we assume manifold is furnished with valve and manometer for all outputs, and input).
    • Over-pressure valve ("Fisher" valve) which must be accessible for adjustments.
    • Cooling water connection point.
    • Diesel fuel connection point.
    • Connection point for signal cable (for remote control and monitoring).
  4. Supply of diesel fuel:
    • Pipe or hose interface: Threading type / dimensions.
    • What is estimated diesel fuel consumption at max HP air capacity 375 CFM.
    • Recommended volume of diesel tank within container.
    • Is filter on diesel feed line required.
  5. Regarding HP air:
    • Number of manifold outlets? (At least 4 ea).
    • Install oil / water filter in HP outlet?
  6. How compressor can be operated and monitored from vessel instrument room.
  7. Location of HP air pressure sensor, and distribution of signal from this unit.
  8. Cooling water requirements:
    • Salt / freshwater.
    • Flow rate [m3/hour].
    • Pressure range.
    • Max allowed temperature (of relevance if compressor container used on research vessels operating in tropical waters).
    • Pipe / hose interface: Threading type / dimensions.
  9. IP-connection to internal compressor instrumentation system, permitting factory remote diagnostics and error location ?
  10. Service requirement, both of diesel engine and compressor. Service agreement: Scope, terms and cost?
  11. Recommended set of spare parts.
  12. Required operator qualifications or certifications ?
  13. This LMF brochure "LMF high-pressure oil-free compressor for offshore seismic exploration" mentions new oil free compressor type (eliminating oil contamination of HP air; and the need for change and disposal of used oil). Is this compressor type relevant for our application?
Department of Earth Science
University of Bergen
N O R W A Y