Specification of 4x600 MW Boiler

—  Top Supported

—  Single Drum

—  Fusion welded water wall panels

—  Controlled circulation

—  Internal Firing

—  Oil and Coal Fired (Tangential Fired)

—  Wet Bottom Ash

—  Balance draft

—  Sub-critical

—  Single Reheat

—  Single Arch

DEFINITION OF BOILER

Boiler means any closed vessel exceeding 22.75 liters in capacity and which is used expressively for generating steam under pressure  external to (outside) the boiler and includes any mounting or other fitting attached to such vessel, which is wholly or partly under pressure when the steam is shut off.

Steam Pipe means any pipe through which steam passes from a boiler to a prime mover, or other user or both, if pressure at which steam passes through such pipe exceeds 3.5 kg/cm² above at. pr. or such pipe exceeds 254 mm in ID and includes in either case any connected fitting of a steam pipe.

Welding and advantages of welding

Welding:- Welding is a process of joining similar or dissimilar metals with or without application of heat and pressure alone and with or without application of filler material.

Advantages of welding:-
                                       . Welding is a permanent joint
                                       . Strength will be equal to or more than the strength of the base metal
                                       . Welding can be done in any position

What are the four types of inspection stage

Four types of inspection stage:-
                                               1.Hold
                                               2.Witness
                                               3.Surveillance
                                               4.Review

1.Hold:- QA\QC organization shall be noticed of the timing of inspection or test in advance,inspection or test shall not carry out QA\QC organization representative in attendance.

2.Witness:- Copy above lining (Hold) inspection or test shall be performed as schedule.if the QA\QC organization representative is not present.

3.Surveillance:- QA\QC organization monitoring the work in process without notice from construction organization.

4.Review:- Review and approved all documents.

Weld types: Weld symbols

FIELD WELD SYMBOL
 Field weld symbol indicates that weld is to be made at a place other than that of initial construction

COMPLETE PENETRATION

BASIC TYPES OF WELD JOINTS

1.Fillet weld
2.Corner weld
3.Butt weld
4.Edge weld
5.Lap weld

Mechanical properties of weld metals and these types.

The mechanical properties of a metal describe its suitability for any given application and provide a performance. Four types of mechanical properties-

1.Strenghth

2.Hardness

3.Ductility

4.Impact Resistance