CONVERSION OF UNITS 2

CONVERSION OF UNITS 2

CONVERSION OF UNITS 2

CONVERSION OF UNITS

CONVERSION OF UNITS

                CONVERSION OF UNITS

BALL BEARING

BALL BEARING

                     BALL BEARING

Deep grove ball bearing

Simple in design
Have uninterrupted raceway
Can accommodate both radial and axial loads
Are non separable

 Two types of deep grove ball bearing

single row           double row

Self aligning ball bearing

self aligning ball bearing have two rows of balls with a common sphered raceway in the outer ring
Available in cylindrical or tapered bore
Are non separable

Angular contact ball bearing 

Angular contact ball bearing have one high and one low shoulder on each rings
Particularly suitable of combined loads that is simultaneously acting radial and axial
The axial load carrying capacity of angular contact ball bearing increases with the increase in contactt angle 

Two types of angular contact ball bearing

single row               Double row 

Four point contact ball bearing

Accommodate axial load in both direction
They need less axial space then double row bearing
Have a contact angle of 35 degree
The bearing are separable.

Thrust ball bearing

The baring are separable so that mounting is simple
Can accommodate axial load in one direction
Suitable for medium speed.

Bearing and Bearing Types

Bearing and Bearing Types

             Bearing and Bearing Types

Definition of Bearing 

A bearing is the machine element which support another moving machine element (shaft). It permits the relative motion B/W the contact surfaces while carrying the load.

Classification of Bearing

1)Depending upon the direction of load to be support

a)Radial Bearing
b)Thrust Bearing

 2)Depending upon nature of contact

a)sliding contact bearing
b)Rolling contact bearing

Types of Bearing 

Bearing can be categorized into two main types

1)Plain bearing(sliding contact)
2)Anti friction bearing(Rolling contact)

1)Sliding contact

a)Radial bearing
b)Thrust bearing
c)Guide bearing

2)Anti friction or Rolling contact Bearing

a)Ball bearing
b)Roller Bearing

Ball bearing

a)Deep groove ball bearing
b)Self aligning ball bearing
c)Angular contact ball bearing
d)Four point contact ball bearing

Roller bearing

a)Cylindrical roller bearing
b)Needle roller bearing
c)Spherical roller bearing
d)Tapered roller bearing

Heat Exchanger

Heat Exchanger

                        Heat Exchanger

Heat Exchanger:

A device for transferring heat from one media to another.

Classification of heat exchanger: 

Classification of heat exchanger according to transfer process

1) Indirect contact type                  (2) Direct contact type 

According to number of fluids 

 1) Two number          ( 2) Three number      (3) N-number 

According to surface compactness 

1) Gas to liquid        (2) liquid to liquid 

According to construction

1)Tube and shell type        (2)  Plate type 

1)Tube type

A) I tube bundle  (2)  U tube bundle 

  

2) Plate type 

1)PHE          (2) Sprial     (3) Plate coil        (4) Printed circuit 

According to flow arrangement

1) Single Pass         (2) Multi pass

Piping drawing and symbols

Piping drawing and symbols

                         Piping and isometric Drawing 

Isometric:

Unlike orthographic, piping isometrics allow 

the pipe to be drawn in a manner by which the

 length, width and depth are shown in a single

 view. Isometrics are usually drawn from 

information found on a plan and elevation 

views. The symbols that represent fittings,

Valves and flanges are modified to adapt to 

the isometric grid. Usually, piping isometrics 

are drawn on

HOW TO READ A PIPING ISOMETRIC

A pipe into a isometric view, is always drawn by a single line. This single line is the center line of the pipe, and from that line, the dimensions measured. So, not from the outside of a pipe or fitting.
The image below shows a orthographic view of a butt welded pipe with three sizes (A, B, C).

·         The A size is measured from the front to the center line of the elbow / pipe.

·         The B size is measured from center line to center line.

·         The C size is like the A size, measured from the front to the center line of the 

Drawing Isometric Offsets:

Offset:

indicates that a piece of pipe is shifted from one line of direction to another

 is done with a fitting (typically a 45° elbow)

 one of the few times you might have “artistic license” in making a piping drawing

Horizontal offsets:

If you draw a horizontal pipe with a 45°

Elbow running form southeast to northwest

Technically correct, it would look like a

Vertical line… to prevent confusion, the

Offset is drawn 22 ½ ° from vertical to give.The illusion of the angle

Vertical Offsets

These offset can get just as confusion as the horizontal offset

                                   

                                     PIPE FITTING SYMBOLS:

Fabricate a 90 Degree Elbow from pipe

Fabricate a 90 Degree Elbow from pipe

         Fabricate a 90 Degree Elbow From Pipe

Formula

D= Dia of pipe(given)

R= 1.5D/1D/5D As per req

CF=2­Πr

Length of pipe required= Cf/360×Deg of Elbow

Deg cut=Deg/no of pieces (Given)

L1∞L2=(Tan deg of cut)×OD

Cutting mark=(L1∞L2)/2 From divided point

Example

Fabricate a 1.5D and 90 degree elbow 10”OD Sch 40 and make it with 4 no of pieces.

Required Length of pipe to fabricate

OD=10”      =10.75Inch (from pipe sch table)

                    =10.750×25.4=273mm

R=1.5D       =273×1.5=410mm

cF                =2×3.14×410=2576mm

Length of pipe req=cf/360×Deg of elbow

Deg of elbow=90

Length of pipe req =2576/360×90=644mm

Adding cutting and grinding allowances of 15mm its is 659 mm

Deg of cut= Deg/ no of pieces=90/4=22.5

L1∞L2=(Tan Deg cut)×OD=0.414×273=113mm

Cutting mark=(L1∞L2)/2from divided point =56

welding and joints

welding and joints

                    welding and welding joints

Definition

 

To join by applying heat sometimes with pressure and

 some time with an intermediate or a filler metal 

having a high melting point

A welding joints is a permanent joints use 

extensively in fabrication process . An electronic process for fusion welding arc or gas welding is use for fusion of the martial 

Classification of welding

1)Fusion welding

2)Forge welding

1)Fusion welding

In this process the parts to be joined in proper 

position while the molten martial Is supplied to the

 joint. By heating the joints surface become plastic 

molten. when the molten melt the joints is formed

2)Forge welding

 In this type of welding the parts are first heated to a 

proper temperature in a furnace or forge and then 

hammered.

Classification of fusion welding

1)Gas welding

a)Air acetylene

b)Oxy acetylene

c) Oxy hydrogen welding

2)ARC Welding

a)Carbon arc welding

b)Plasma arc welding

c)Shield metal arc welding

d)T.I.G Tungsten inert gas

e)M.I.G Metal inert gas

3)Resistance welding

a)Spot welding
.

b)Seam welding

c)Flash butt welding

4)Solid state welding

a)Cold welding

b)Forge welding

c)Hot pressure welding

d)Roll welding

Welding joints

We used different types of welding joints butt lap T 

joints etc

In but joint we used different  types of bevel  

FABRICATION PROCESS

FABRICATION PROCESS

                     

                            FABRICATION PROCESS

Structural steel fabrication can be carried out in shop or at the construction site. Fabrication of steel work carried out in shops is precise and of assured quality, whereas field fabrication is comparatively of inferior in quality.

Structural steel passes through various operations during the course of its fabrication. Generally, the sequence of activities in fabricating shops is below 

1) surface cleaning 

2)cutting and machining according to drawing 

3)punching and drilling

4)bending rolling and straightening

5)fitting

6)fastening like riveting welding

7)finishing

8) Quality control 

9)surface treatment

10)Transportation

 Surface cleaning:

 Structural sections from the rolling mills may require surface cleaning to remove mill scale prior to fabrication and painting.

 Cutting and machining according to drawing :

Following surface preparation, cutting to length is always the first process to be carried out, and this is done by any of the following methods.

I)Shearing and cropping

II)Flame Cutting or Burning

III) Arc Plasma Cutting

VI)Cold Sawing

 Punching and Drilling
Most fabrication shops have a range of machines, which can form holes for connections in structural steel work. The traditional drilling machine is the radial drill, a manually operated machine, which drills individual holes in structural steel work. But this method has become too slow for primary line production. 

Straightening, Bending and Rolling: 
Rolled steel may get distorted after rolling due to cooling process. Further during transportation and handling operations, materials may bend or may even undergo distortion. This may also occur during punching operation. Therefore before attempting further fabrication the material should be straightened. In current practice, either rolls or gag presses are used to straighten structural shapes. 

Fitting:
Before final assembly, the component parts of a member are fitted-up temporarily with rivets, bolts or small amount of welds. The fitting-up operation includes attachment of previously omitted splice plates and other fittings and the correction of minor defects found by the inspector.

Fastening like riveting welding:
The strength of the entire structure depends upon the proper use of fastening methods. There are three methods of fastening namely bolting, riveting and welding. A few decades back, it was a common practice to assemble components in the workshop using bolts or rivets. Nowadays welding is the most common method of shop fabrication of steel structures. In addition to being simple to fabricate, welded connection considerably reduce the size of the joint and the additional fixtures and plates


Finishing:
Structural members whose ends must transmit loads by bearing against one another are usually finished to a smooth even surface. Finishing is performed by sawing, milling or other suitable means. Several types of sawing machines are available, which produce very satisfactory finished cuts.

Surface treatment:
Structural steel work is protected against corrosion by applying metal or paint coating in the shop or at site.