mazagonmazagondock ltd.dock ltd. june, july june, july 20122012

roy thomas101200902124 sep., 2012

introductionintroduction Mazagon dock Limited Mumbai is an ISO 9001:2008 company is one of the leading

shipbuilding and offshore fabrication yards in India. It specializes in manufacturing of warships and submarines for the Indian Navy, as

well as offshore platforms and associated support vessels for offshore oil drilling. It also builds tankers, cargo bulk carriers and passenger ships and ferries.

It’s current projects are:

TYPE CLIENT

P-15 Alpha Indian Navy

P-15 Bravo Indian Navy

P-17 Alpha Indian Navy

P-17 Indian Navy

Multipurpose Service Vessel Cotemar

design departmentdesign department All the detailing that is required to manufacture is provided by the Design

Department.

o Forward Design Group (FDG)o Structural Department (SDO)o Outfit Department (ODO)o Engineering Department (EDO) o Electrical Department (LDO)

forward design groupforward design group The forward design group can be sub divided into 3 sections:

Basic Design Group

Cost Estimation Cell

Contract and Marketing Cell

The general progression of any typical order follows the following sequence:

1. Pre-Contract Stage:

2. Post-Contract Stage:

structural department

Structural design group mainly deals with the modelling of the ship. Modelling is carried for hull detailing and sheeting, bulkheads,

stiffeners, etc. Based on the lifting capacity of assembly units available in the

shop, unit erection plan is prepared. Optical section will prepare nesting and cutting plans using faired

hull surface designs and curvature requirements. Planning section prepares the part list and cutting document to be sent to material requisition store and production shops.

Mould loft section carries out the preparation of wooden templates of each frame in 1:1 scale for accuracy in plate bending & unit erection.

outfitting departmentoutfitting department To start with the hull outfit, first drawing should be prepared is an Access Plan of the

whole ship based on its GA plan. the detail production drawings of individual items covering various systems are prepared. The outfitting items which remain on the deck and inside of the ship are mainly as follows:

SHIP’S FITTINGS (excluding machinery and electrical)BOLLARDSFAIRLEADSACCESSBOOMS & DAVITSWINDOWS AND SIDE SCUTTLESDECK EQUIPMENTSLIGHT & SOUND SIGNAL ARRANGEMENTSFIRE FIGHTING ARRANGEMENTMOORING AND BERTHING ARRANGEMENTCARGO ACCESS EQUIPMENT

engineering & electrical engineering & electrical departmentdepartment

The engineering department mostly deals with various systems & machinery especially in the engine room, whereas, the electrical dept. deals with the various electrical systems required in the ship, specially in the wheel house.

The electrical dept. also deals with the weapons & weaponry systems as required in naval vessels.

The propulsion & power generation system is handled by the engineering department.

border outpost vessel A border outpost or BOP is an outpost maintained by

a sovereign state on its border one of a series placed at regular intervals, to watch over

and safeguard its border with a neighbouring state with whom it may or may not have cordial relations.

Such posts are manned by border guards and are at all times connected by radio communication with on-going border patrols in their region and the force headquarters in the interior of the country for their day to day functioning, passing on intelligence and for requesting supplies and any needed reinforcements in emergencies.

scantlings Scantlings, steel weight, LCG & VCG of the bare hull were

calculated for a 46 m long Border Outpost (BOP) vessel. The scantling calculations for the above were done using the empirical formulae given in Part-3 of the IRS rule book. Given parameters L=46m B=12m T=1.2m D=3.4m General Arrangement Diagram

estimation of lt wt., vcg, lcg… With the given GA, the approximate area of the shell plate

was determined and multiplied with the thickness and density of steel to get the steel weight of the vessel.

The shell thickness formulae will have a design pressure term which is taken from different values obtained from various conditions and corresponding formulae. The appropriate value is considered for calculation.

Number of frames is found from the GA where the frame numbers are marked. All the frames under the engine compartment and every fourth floor elsewhere are considered to be floor plates.

The stiffener weight is calculated using the chart which gives the weight per length of a particular stiffener type. The length of the stiffener is determined from the GA and multiplied with the wt./length to get the stiffener weight.

Weight of the brackets is considered to be about 10% of the stiffener weight

The LCG is calculated by adding all the moments of the various shells, superstructures, frames, etc. about the aft and dividing it by steel weight.

The VCG is calculated by adding all the moments of the various shells, superstructures, frames, etc. about the keel and dividing it by steel weight.

thank you