# Pune University BE Deep Water Technology Question Papers

B.E. (Petroleum) DEEP WATER TECHNOLOGY (2008 Pattern) (Elective – III) (Sem. – II)

Time :3 Hours]                                                                                              [Max. Marks :100

Instructions to the candidates:

Answer 3 questions from Section I and 3 questions from Section II.

Answers to the two sections should be written in separate books.

Neat diagrams must be drawn wherever necessary.

Pigures to the right indicate full marks.

Use of logarithmic tables slide rule, Mollier charts, electronic pocket calculator and steam tables is allowed.

Assume suitable data, if necessary.

SECTION – I

 Q1 a)

A 18-3/4″ subsea stack having two 5M shaffer spherical annular preventers, four Hydryl MPL, 10M ram preventers and six fail safe valves of 10M working pressure, requiring 1.1 gallons fluid to open or close each valve A 3000 psi working pressure BOP control unit at surface is used to operate BOP. Calculate the number of accumulator bottles of 11 gallons capacity required in the unit. The minimum operating pressure of accumulator should not be less than 1200 psi data given as      [8]

18-3/4″, 5M shaffer spherical annular preventer, volume to close = 48.16 gallons volume to open = 37.61 gallons.

18-3/4″, 10M hydril MPL Ram preventer

Volume to close one ram = 17.10 gallons Volume to open one ram = 15.60 gallons Take 50% safety factor, precharge pressure is 1000 psi.

b) Draw subsea well head system and compair with surface well head system.

[8]

OR

Q2) a) Discuss Lower Marine Riser (LMRP) Package components in detail. [8]

b)        What do you understand by “Station keeping” of a drill ship or a submersible? Discuss any one station keeping method.                                                                     [8]

P.T.O.

Q3) a) Explain subsea cementation process for 9-5/8″ casing with suitable sketch.

[8]

b)

 / \ Y 1-y

Show that minimum horizontal stress is                                                        [5]

y- poisson’s ratio

ov – vertical stress oh – horizontal stress

c)         Calculate principle stresses and angle of failure plane using equations. If o x = 17.5 psi oy = 12.5 psi Txy = 4.33 psi are normal stress of state.

[5]

OR

Q4) a) Discuss stresses around well bore for linear elastic behaviour of formation and plot a tensor.                                                                                                                   [6]

b)        Discuss gas hydrate problem and remedy in deepwater drilling. [6]

c)         What is ECD? Discuss effect of ECD on Bottom hole pressure. [6]

Q5) a) What are different offshore mobile drilling units? Explain with the help of neat sketches.                                                                                                                               [8]

b) Using linear wave theory find out wave length and wave celerity for a propagating wave with a wave period of 12 second in deep and shallow water. For same wave find out maximum horizontal and vertical displacement of water particle in deep and shallow water condition if wave height is 8m.                                                             [8]

OR

Q6) a) Write short notes :                                                            [12]

i)        ROV.

ii)           Airy’s theory of linear waves.

b) Discuss different types of principle motions on a floating offshore rig. [4]

SECTION – II

Q7) a) What are different types of platform? Discuss advantages and disadvantages of concrete gravity platform.                                                                                [8]

b) Discuss effect of wind, wave and current forces on Jack up/fixed platform.

[8]

OR

Q8) Discuss fixed offshore production platform design and planning considerations in detail.  [IT]

Q9) a) Discuss any one subsea completion tree with suitable sketch.      [8]

b) Discuss design considerations of 3-phase separator on offshore production platform.  [8]

OR

QIO) a) Discuss any type of EOR technique with suitable sketch.         [12]

b) Write short note on production monitoring and control system. [4]

Qll) a) Write short notes on :                                                      [12]

i)            FPSO.

ii)           Storage tanks.

b) Discuss logistic considerations in exploratory and drilling operations (offshore).         [6]

OR

Ql2) a) Discuss the assumptions and derive Weymount equation for horizontal gas flow in a pipe                                                                                          [12]

 0.5
 (p2 – p 2)D 5 rg TZFL
 T C Tb– P„
 q =

b) Discuss drill stem test in brief.                                                                                                                         [6]