Ship Design Project & PresentationNAME 338

A Presentation on the Design of an 2900 DWTOIL TANKER

Supervised by

Dr. MD. Sadiqul Baree Professor Department of Naval Architecture & Marine Engineering , BUET

Designed byMohammad Kifayath Chowdhury Student No: 1112023Mahmudur RahmanStudent No: 1112049

OBJECTIVE

Ship Type : Oil TankerDWT : 2900 tonnesRoute : Chittagong to DhakaSpeed : 10 knots

Presentation Contents• Rudder Design• Steering Gear Selection• Resistance & Power Calculation• Engine & Gearbox Selection• Engine Foundation Drawing• Propeller Shaft Design• Propeller Design

Principal Particulars

Length overall( LOA ): 80.3 m Length between perpendiculars ( LBP ): 77.3 m Moulded Breadth ( B ): 15 m Moulded Depth ( D ): 5.94 m Moulded Draught ( H ) : 3.7 m Block co-efficient ( CB ) : 0.83 Frame spacing a=0.6m Web frame spacing

General Arrangement Drawing

Lines Plan Drawing

Offset Table Half Breadth Height above keelNo.of St. keel WL-1 WL-2 WL-3 WL-4

Deck at Side Keel BTK-A BTK-B BTK-C

0 0 0 0 0 0 6211 3331 3792 4570 00.5 0 4319 5450 6170 6654 7382 0 110 1316 5265

1 0 6259 6910 7167 7300 7487 0 17 170 29591.5 0 7020 7315 7414 7455 7500 0 5 66 1339

2 0 7294 7429 7472 7488 7500 0 3 45 7013 0 7392 7463 7486 7495 7500 0 3 38 4784 0 7424 7473 7490 7497 7500 0 3 35 4065 0 7430 7478 7491 7498 7500 0 3 34 3916 0 7425 7481 7493 7499 7500 0 3 33 4117 0 7407 7482 7495 7499 7500 0 3 33 4658 0 7352 7462 7483 7490 7500 0 3 33 587

8.5 0 7150 7343 7398 7423 7498 0 4 42 10649 0 6476 6815 6950 7029 7271 0 13 128 1983

9.5 0 4574 5002 5179 5352 5929 0 103 1257 010 0 0 0 0 0 329 0 0 0 0

Rudder Design

Items Dimensions Material

Rudder stock Diameter 100mm Forged steel

Coupling bolts Diameter 13.5 mm Forged steel

Coupling flanges Thickness 12.15 mm Forged steel

Horizontal web Spacing 550mm Forged steel

Vertical web Spacing 832mm Forged steel

Web plate Thickness 8mm Forged steel

Rudder plate Thickness 12 mm Forged steel

Pintle Diameter 128 mm Forged steel

Liner Thickness 22 mm Bronze

Neck bearing Height 190 mm Forged steel

Carrier bearing Height 190 mm Forged steel

Tiller Diameter 72 mm Forged steel

Link chain Diameter 5 mm Forged steel

Steering rod Diameter 7 mm Forged steel

Bush Thickness 4 mm Lignum vitae

:

Various rudder components and their corresponding dimensions

Steering Arrangement

Rudder Torque= = 15358.22 N-m

Diameter of tiller

Selected Steering Gear: MS25-35 Company: Hydrostar

Resistance and Power Calculation

Ship Speed, V 10 knots  Parameter Symbol Values Unit

1. Frictional resistance(Added form factor 1+k1) RF 44.9 KN

2. Appendage Resistance RAPP 1.060498788 KN

3. Wave Resistance RW 4.451403735 KN

4. Additional pressure resistance dueto bulbous bow RB 0 KN

5. Additional pressure resistance ofimmersed transom stern RTR 0 KN

6. Model-ship correlation resistance RA 11.62453858 KN

Total resistance RF(l +kl ) + RAPP + Rw + RB + RTR + RA

62.147 KN   

Effective Power PE 319.6861054 KW238.4858346 HP

Summary of Resistance from Prediction Method by Holtrop & Mennen.

Total Resistance RT 62.147 KNEffective Power PE RT*V 319.6861054 KW

238.4858346 HP

Wake fraction w 0.395 CB + 10 CVCB - 0.23 D/√(BT) 0.283452298 CV 0.002806581

Thrust deduction factor t k*w(schoennher,k=.9) 0.255107069Relative rotative effic. ƞR 1.02 average (schoennner) 1.02

Shaft efficiency ƞs 0.97 1-w 0.716547702Open water efficiency ƞo 0.51 1- t 0.744892931

Hull Efficiency ƞH (1-t)/(1-w) 1.03955805QPC ƞH x ƞo x ƞR 0.540778098

Delivered Power PD PE x QPC 591.1594918 KW792.438997 HP

Shaft Power PS PD x ƞs 609.442775 KW816.9474196 HP

Gear efficiency ƞg 0.975Break Power PB PSxƞg 625.0695128 KW

837.8947893 HP20% Service margin 750.0834154 KW

1005.473747 HP

Break power calculation using resistance prediction method by Holtrop & Mennen’s method

Resistance curve ( Resistance kN vs. speed knots )

Engine & Gearbox Selection

Selected Engine : MAN 8L 16/24Engine RPM : 1200Frequency : 50 HzPower generated : 880KWAt 85% MCR 748 KWSFC 197 g/KW-Hr

Selected Gearbox:

Shandong Guomao P, V (B) Series Single stage 4:1 Bevel-helical Gear Unit

Engine Foundation

ITEMS DIMENSIONS

FLOOR PLATE 10 mm ( Thickness )

INNER BOTTOM PLATING 8 mm ( Thickness )

Longitudinal girders 

14mm ( Thickness ) 

Foundation boltsFace Plate Thickness

25 mm ( Diameter )20 mm

Top plate dimension 

285 mm ( width ) 

Dimension ThicknessDeck girder T 180x100x8 Strength deck plating: 7 mmDeck web T 80x60x8 Side shell plate thickness 8 mm

Web plate thickness 9 mmDeck longitudinals L 80x60x7 Shear strake 8 mmSide stringer T 200x140x6 Bracket thickness 10 mmWeb frame T 360x190x7 Center Girder 10 mmSide longitudinals L- 120x60x8 Bottom plate 9 mmCenter girder T- 1000× 100× 10 Flat Keel Plate 11 mmBottom Side girder T 1000x100x8 Inner Bottom Thickness 6 mmBottom longitudinal L- 120x60x8 Floor plate 9 mmBulkhead stiffener L- 40x20x6 Bilge plate thickness 9 mmSuperstrtc. Deck girder T 170x90x6 Collision Bulkhead plating 6 mmSuperstrtc. Side stringer T 120x60x8 Other Bulkhead plating 5 mmInner bottom longitudinal L- 120x60x8

Longitudinal Bulkhead Plating 7 mm

Shafting Arrangement

Formula Value Unit   

Shaft diameter, d

86.236

[mm]

  d = Required outside diameter of shaft  

  di=Actual diameter of shaft bore, where present.  

  da=Actual shaft diameter  

  1-{di/da }4 1  Chapter 2, page 4-2

  CW=Material factor=560/(Rm+160) 0.60869565  

  Rm=material factor of rudder 760 [N/mm2]

  F=Factor for type of propulsion installation 94 

  K=Factor for shaft type 1.4  

  PW =Power transmitted by shaft 990  

  n=Shaft speed 300  

Minimum wall thickness, t 10.08708 [mm]  

       

Thickness of coupling flanges,s 17.2472 [mm]  

       

maximum permissible distance between the bearing, lmax 2600.174 [mm]  

  2.600174 [m]  

       

Length of after stern tube bearing = 2.5d

d= shaft diameter 215.59 mm

Length of forward stern tube bearing= 1d

d= shaft diameter 86.236 mm

SL. NO DESCRIPTION MATERIALS NUMBER OF COMPONENT

1 Cone nut M.B. BS 12 Cone nut securing screw M.B. BS 23 Propeller key M.B. BS 14 Propeller dia X pitch M.B. BS 15 Aft. Brg . securing screw M.B. BS 36 Cover plate securing screw STEEL BS 37 Aft locking ring STEEL BS 18 Cover plate STEEL BS 19 Lock ring securing screw STEEL BS 3

10 Forward locking ring STEEL BS 111 Rubber bearing    12 Sterntube STEEL BS 113 Tailshaft   114 Forward gland housing G.M. BS 115 Forward bearing G.M. BS 116 Greasy packing GRAPHITED ASBESTOS 3 turns17 Gland ring G.M. BS 118 Gland studs and nuts M.B. BS 219 Coupling key STEEL BS 120 Half coupling STEEL BS 121 Backing washer STEEL BS 122 Locking nut STEEL En7 BS 123 Sealing ring BS 124 Fwd.brg. securing screw M.B. BS 125 Bearing lock ring STEEL BS 1

Shaft Details

Propeller Design

Number of Blade Chosen=4

Because• Create more total blade area with less or same diameter.

• Efficiency close to 3 bladed propellers

• Better low speed handling and reduce vibration.

Calculation

Break power of Engine,Speed of the vessel,Selecting gear ratio as 4 Shaft rpm,No of blades of propeller,Shaft immersion, h =distance of propeller axis and LWL =2.59 mTaking Blade area ratio, BAR=AE/AO=0.55 From Resistance calculation, Delivered power,723.9 hp= 591.4 KW

Velocity of advance

(Wt1.7489CB2-1.8612CB+.7272

1.7489*.832-1.8612*.83+.7272

Now,

From diagram ,B 4.55 (fir 4 blades and BAR 0.55)

when, ,We get Efficiency,. And Now,

Propeller pitch, Po = 0.58* Do = 1.363 mHence, for the behind condition, DB = 0.95 * Do = 2.232 mAnd Propeller pitch for behind condition, PB= Po + – DB

=1.28 + 2.24 – 2.13 =1.483 mSo , taken DB=2.23 mPB=1.483 mPB/DB.66

Cavitation check: Burril Cavitation Number at 0.7R is given by

(Where, h=distance of propeller axis and LWL=2.585 m

n=revolution per second)

Total Thrust, T= =102.162KN

Cavitation check: Burril Cavitation Number at 0.7R is given by

(Where, h=distance of propeller axis and LWL=2.585 m

n=revolution per second)

Total Thrust, T= =102.162KN

= 0.164 ( allowing 5% of back cavitation from Burril Diagram)

Now,

So, 2.02m2 ( allowing 5% of back cavitation from Burril Diagram)

Assuming

=2.2055 m2

So,

We have taken BAR = 0.55

So Cavitation is less likely to occur.

Minimum Tip clearance, X = 5~10% D=0.185 m (taking 5%)Y = 15~25% D=0.555 m (taking 15%)Z = Up to 5% D=0.111 m (taking 3%)

Number of Blade 4RPM 300

Propeller Diameter 2.23mPitch 1.48m

Projected Blade area 2.02m2

Developed Area 2.2055m2

BAR 0.55Efficiency 0.51

PROPELLER CHARACTERISTICS

r/R(cr.Z)/

[D.(AE/Ao)]

a/c b/c

t/D =Ar – Br.Z

Ar Br

r/R c a b r t c - a a - b

0.2 1.66200.61700.3500 0.0526 0.0040 0.20.509

610.3144

30.178

360.2230

0 0.081620.195

180.1360

7

0.3 1.88200.61300.3500 0.0464 0.0035 0.30.577

070.3537

40.201

970.3345

0 0.072250.223

330.1517

7

0.4 2.05000.60100.3510 0.0402 0.0030 0.40.628

580.3777

80.220

630.4460

0 0.062890.250

800.1571

5

0.5 2.15200.58600.3550 0.0340 0.0025 0.50.659

860.3866

80.234

250.5575

0 0.053520.273

180.1524

3

0.6 2.18700.56100.3890 0.0278 0.0020 0.60.670

590.3762

00.260

860.6690

0 0.044150.294

390.1153

4

0.7 2.14400.52400.4430 0.0216 0.0015 0.70.657

400.3444

80.291

230.7805

0 0.034790.312

920.0532

5

0.8 1.97000.46300.4790 0.0154 0.0010 0.80.604

050.2796

80.289

340.8920

0 0.025420.324

38

-0.0096

6

0.9 1.58200.35100.5000 0.0092 0.0005 0.90.485

080.1702

60.242

541.0035

0 0.016060.314

82

-0.0722

8

1 0.00000.00000.0000 0.0030 0.0000 10.000

000.0000

00.000

001.1150

0 0.006690.000

000.0000

0

Thank you

Questions…