Dockmaster S Training Manual

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Dockmaster S Training Manual

Transcript Of Dockmaster S Training Manual

DOCKMASTER’S TRAINING MANUAL
DOCKMASTER TRAINING MANUAL
By
HEGER DRY DOCK, INC.
© April 2018 i

DOCKMASTER’S TRAINING MANUAL

TABLE OF CONTENTS

SECTION 1 – DRY DOCK TYPES

Page

1.1 Basin Dry Docks.......................................................................................... 1-2 1.2 Floating Dry Docks ...................................................................................... 1-14 1.3 Marine Railways .......................................................................................... 1-36 1.4 Vertical Lifts ............................................................................................... 1-47 1.5 Marine Travel Lifts ....................................................................................... 1-50

SECTION 2 – DOCKING PLAN
2.1 Docking Plan .............................................................................................. 2-1 2.2 Modifying the Docking Plan ........................................................................... 2-12 2.3 When There is No Docking Plan ..................................................................... 2-15

SECTION 3 – SHIP CHARACTERISTICS IMPORTANT TO DRY DOCKING

3.1 3.2 3.3 3.4 3.5 3.6 3.7 3.8 3.9 3.10

Dimensions & Clearances ............................................................................. 3-1 Ship Strength ............................................................................................. 3-2 Hydrostatic Properties.................................................................................. 3-4 Calculation of Displacement .......................................................................... 3-4 Longitudinal Center of Buoyancy (LCB)........................................................... 3-8 KM & Stability ............................................................................................. 3-11 KB ............................................................................................................ 3-13 Stern reference Point (SRP) .......................................................................... 3-13 Aft Perpendicular (FP and Forward Perpendicular (FP)....................................... 3-13 Amidships .................................................................................................. 3-13

SECTION 4 – BLOCK LOADING

4.1 4.2 4.3 4.4 4.5 4.6 4.7 4.8 4.9 4.10

Block’s Initial Height Relative to the Others..................................................... 4-1 Bearing Area of Ship on Block ....................................................................... 4-3 Types of Materials ....................................................................................... 4-4 Position of Block Under the Ship and Weight of Ship ......................................... 4-5 Trapezoidal Loading Equation........................................................................ 4-8 Interrupted Keel Bearing .............................................................................. 4-11 Varying Width Keel ...................................................................................... 4-20 Moment Area Method................................................................................... 4-28 No. Of Side Blocks Required to Resist Hurricane Forces..................................... 4-45 No. Of Side Blocks Required to Resist Earthquake Forces .................................. 4-49

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DOCKMASTER’S TRAINING MANUAL TABLE OF CONTENTS

SECTION 5 – STABILITY

Page

5.1 Stability of Vessel Afloat............................................................................... 5-1 5.2 Stability of Vessel at Time of Keel Touch Down ................................................ 5-7 5.3 Stability of Vessel at Time of Hauling Side Blocks ............................................. 5-10 5.4 Draft at 0 GM (Point of Instability .................................................................. 5-12 5.5 Vessel Stability at Undocking ........................................................................ 5-12 5.6 Example of Grounding Stability Calculations .................................................... 5-14 5.7 Stability of Floating Docks ............................................................................ 5-19 5.8 Multiplication Effect ..................................................................................... 5-25

SECTION 6 – PREDICTING VESSEL CONDITION AT UNDOCKING
6.1 Establishing the Baseline Docking Condition .................................................... 6-1 6.2 Tracking the Effects of Weight Changes .......................................................... 6-8 6.3 Calculating Vessel Drafts at Float Off.............................................................. 6-9 6.4 Calculating Vessel Stability at Float Off ........................................................... 6-11 6.5 Calculating Vessel List at Float Off ................................................................. 6-12 6.6 Summary of Vessel Condition at Float Off ....................................................... 6-12

SECTION 7 – BLOCK CONSTRUCTION
7.1 Principles & Concepts................................................................................... 7-1 7.2 Types of Blocks ........................................................................................... 7-2 7.3 Blocking Material......................................................................................... 7-4 7.4 Fastenings ................................................................................................. 7-8 7.5 Construction of Keel Blocks........................................................................... 7-8 7.6 Construction of Side Blocks........................................................................... 7-13

SECTION 8 – DOCKING PROCEDURES
8.1 Advance Preparation .................................................................................... 8-1 8.2 Preparation of the Docking Facility ................................................................. 8-2 8.3 Pre-Docking Checks ..................................................................................... 8-2 8.4 The Docking Operation................................................................................. 8-3 8.5 Post-Docking Checks ................................................................................... 8-4

SECTION 9 – VESSEL HANDLING
9.1 Vessel Handling .......................................................................................... 9-1 9.2 Ropes ........................................................................................................ 9-2

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DOCKMASTER’S TRAINING MANUAL

TABLE OF CONTENTS

SECTION 10 – DEVELOPING A PUMPING PLAN

Page

10.1 10.2 10.3 10.4 10.5 10.6

Selecting Dock Drafts for Pumping Plan .......................................................... 10-1 Determining the Load on the Compartments ................................................... 10-3 Determining the Height of Internal Water ....................................................... 10-6 Using Lift Curves in Developing a Pumping Plan ............................................... 10-7 Using the Lift Curves ................................................................................... 10-9 Effects of Venting on Tank Level Readings ...................................................... 10-10

SECTION 11 – DRY DOCK CERTIFICATIONS

11.1 11.2 11.3 11.4 11.5

Commercial Certification .............................................................................. 11-2 U.S. Navy Certification ................................................................................. 11-3 Time Frame for Navy Certification.................................................................. 11-7 Re-certification ........................................................................................... 11-7 Maintenance Program .................................................................................. 11-8

SECTION 12 – DRY DOCK RATINGS

12.1 12.2 12.3 12.4

Rating of Floating Docks............................................................................... 12-1 Rating of Basin Docks .................................................................................. 12-3 Rating of Marine Railways............................................................................. 12-3 Rating of Vertical Lift ................................................................................... 12-4

SECTION 13 – DRY DOCK INSPECTIONS

13.1 13.2 13.3 13.4

Floating Dock Inspections ............................................................................. 13-1 Marine Railway Inspections........................................................................... 13-10 Basin Dock Inspections ................................................................................ 13-21 Block Inspections ........................................................................................ 13-25

SECTION 14 – DRY DOCK TRANSFER SYSTEMS

14.1 14.2 14.3 14.4 14.5

Transfer Arrangement .................................................................................. 14-1 Transfer to and from Floating Docks............................................................... 14-2 Transfer to and from Marine Railways / Vertical Lifts ........................................ 14-4 Transfer Cars.............................................................................................. 14-5 Propulsion Methods ..................................................................................... 14-5

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DOCKMASTER’S TRAINING MANUAL

TABLE OF CONTENTS

SOLVED PROBLEMS

Page

1.

Docking a Patrol Boat on a Marine Travel Lift................................................... A 1-1

2.

Elastic Deflection of Blocks ........................................................................... A 2-1

3.

Calculating Side Block Loads ......................................................................... A 3-1

4.

Reduction of High Intensity Load by adding Ballast........................................... A 4-1

5.

Reduction of High Intensity Load by adding Support ......................................... A 5-1

6.

Interrupted Keel Bearing (Block Omissions) .................................................... A 6-1

7.

Varying Width Keel Bearing .......................................................................... A 7-1

8.

Computation of Knuckle Reaction .................................................................. A 8-1

9.

Preparation of a Pumping Plan ...................................................................... A 9-1

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DOCKMASTER’S TRAINING MANUAL
1.0 - TYPES OF DRY DOCK
DRY DOCK TYPES Dockmasters are not structural or marine engineers and are not expected to design dry docks. They must, however, operate their dock in such a manner as to not exceed the operational limits of the dry dock that have been set by the designer. A basic understanding of how a dock is designed and built provides insight into how and why the dock’s operational limitations have been derived. This knowledge can assist the Dockmaster when he is assessing situations that do not meet standard operating procedures. There are several basic types of dry docks:
 Basin or Graving docks  Floating Dry Docks  Marine Railways  Vertical Lifts  Marine Travel Lifts

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TYPES OF DRY DOCKS © 2018

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DOCKMASTER’S TRAINING MANUAL 1.1 – BASIN DRY DOCKS

Basin or graving docks are large, fixed basins built into the ground at water’s edge, separated from the water by a dock gate.
Basin docks are capable of docking all sizes of vessels, with capacities of over 200,000 tons.
Its basic structure consists of a floor, sidewalls, head (front) wall and a dock gate. Alters (steps) may be incorporated into the side walls for structural stability.

Heger Dry Dock, Inc.

FIGURE 1.1
TYPES OF DRY DOCKS © 2018

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DOCKMASTER’S TRAINING MANUAL

FIGURE 1.2

FIGURE 1.3
Advantages of a basin dock:  Long life expectancy of the basic structure.  Low maintenance costs. (Dock floor and walls can be built of granite or concrete which last a very long time with little maintenance)  There is no limit to the size of the basin dock.

Heger Dry Dock, Inc.

TYPES OF DRY DOCKS © 2018

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DOCKMASTER’S TRAINING MANUAL
 There is no need to worry about ship/dock stability, pumping plans or longitudinal deflection of the dock while docking ships. (Ship stability and block loading must still be addressed, however)
 The basin can be equipped with an intermediate gate that allows flooding of the aft half of the dock while the forward half remains dry.
Disadvantages of a basin dock:  High initial construction cost.  The basin is a fixed structure, which cannot be moved. Makes it harder to re-sell thus harder to get financing.  Routing of men and material is difficult since floor is below grade.  Ventilation and lighting are not good because one has to work “in a hole”.  It is very difficult to enlarge a basin dock.  Transfer is not possible from a basin dock.  Usually slower to operate (Power is inversely proportional to size).
Types of Basin Docks
A basin dock is a large structure cut into the ground that usually has a natural water table. Unless that water can be prevented from reaching the structure, hydraulic pressure will build up tending to “float” the dock out of the ground.

Heger Dry Dock, Inc.

FIGURE 1.4
TYPES OF DRY DOCKS © 2018

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DOCKMASTER’S TRAINING MANUAL
The method of overcoming the hydraulic pressure (by eliminating it or resisting it) determines how the dock is classified. The design of the basin dry dock depends on the hydraulic pressure surrounding the structure. The pressure that develops is a function of its type of construction: full hydrostatic, fully relieved or partially relieved. There are 3 basic types of basin docks: 1) Full Hydrostatic Dock - A full hydrostatic dock uses its weight or an anchorage system to resist the full hydrostatic head at the maximum water table. 2) Fully Relieved Dock - A fully relieved dock uses a drainage system around the entire dock to drain away the water before it can build hydrostatic pressure on the walls and floor. 3) Partially Relieved Dock - A partially relieved dock uses a drainage system under the dock floor to eliminate the hydrostatic pressure on the floor only. The walls resist the full hydrostatic head. Full Hydrostatic Dock No material, not even rock, can be considered impervious in the sense that it will prevent the build up of hydraulic pressure on the structure.
FIGURE 1.5

Heger Dry Dock, Inc.

TYPES OF DRY DOCKS © 2018

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DockStructureTypesPressureBasin Dock