Pocket Welding Guide - A Guide to Better Welding

149 Pages·2010·8.31 MB·English

by  Claire J. Creutzfeldt

EW609
Pocket Welding Guide
A Guide to Better Welding
30th Edition Revised
All Rights Reserved
including the right to reproduce this book or
portions thereof in any form
by
Hobart Institute of Welding Technology
400 Trade Square East
Troy, OH 45373 USA
Filler metal information courtesy
Hobart Brothers Company, Troy, Ohio, USA.
State Board of Career Colleges and Schools
Registration No. 70-12-0064HT
Accrediting Commision of Career Schools
and Colleges of Technology No. 000403
© 2010 Hobart Institute of Welding Technology
ISBN: 978-1-936058-28-0
Cover photo: Hobart Institute Instructor Luke Bailey welding pipe.
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Back Cover 1 11/26/03, 2:08 PM
INTRODUCTION
The Pocket Welding Guide began as a 30-page booklet
with 3.5 x 5.5-inch dimensions that would actually ft
into a shirt pocket. In fact, the early title of the book
was Hobart Vest Pocket Guide to Better Welding.
The booklet contained three types of electrodes, four
essentials of proper welding procedures, types of joints
and welding positions, early welding symbols, some of
the early build your own Hobart welding generators,
and a page of the early “Practical Arc Welding” training
books.
The “up-to-date welding training” was, at that time,
being provided at the Hobart Trade School. It is stated
on the cover, “Thousands of men and women have
received thorough training at the Hobart Trade School,
and have immediately stepped into high paying jobs.”
It goes on to indicate that the training was being
offered “to those interested in preparing for steady
employment in post-war industry.” And that training
was “fully accredited under the G.I. Bill.”
With each new edition, more information was added.
More welding symbols were developed, welding terms
have been standardized and added and today, in its
th
30 edition, the book is 146 pages in length. It has
been completely revised and improved. The Pocket
Welding Guide is a great addition to any welder’s
toolbox. It remains a quick and ready reference.
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FOREWORD
th
This 30 edition of the Pocket Welding Guide is
dedicated to all those who are interested in and work
with any aspect of welding. It covers a wide variety
of subjects that are essential for the student or
beginner and are of interest to the veteran welders,
draftsmen, instructors, supervisors, foremen,
technicians, and engineers.
You are encouraged to strive for the perfect weld.
Putting every effort forth to attain it will make you
more valuable as a welder. No matter what your
task may be, you can do no better than to try for
perfection.
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Contents
Welding & Cutting Processes ..........................................................................6
5 Essentials for Good Welding ..................................................................... 16
Examples of Good & Bad Beads .................................................................. 18
Common Welding Problems, Causes and Cures ................................... 30
Checkpoints for Quality Welding ............................................................... 33
Welding Positions ............................................................................................ 35
Types of Joints ................................................................................................... 37
Welding Symbols ............................................................................................. 38
General Welding Safety ................................................................................. 44
Welding Metals ................................................................................................. 48
Steel Available for Welding........................................................................... 49
Identification of Metals .................................................................................. 50
Typical Preheating for Various Metals ...................................................... 52
AISI-SAE Designation System for
Carbon and Alloy Steels ............................................................................ 53
Cost Saving Hints ............................................................................................. 54
8 Factors to Consider When Selecting Electrodes................................ 56
Metal Cored Wire .............................................................................................. 57
Oven Storage & Reconditioning of Filler Metals ................................... 59
How To Calculate Filler Metal Consumption .......................................... 60
Shielding Gases & Their Uses ....................................................................... 62
AWS Electrode Classifications & Comparative Indices........................ 63
GMAW Short Circuiting Transfer Welding
Parameters & Shielding Gases ............................................................... 74
GMAW Spray Transfer Welding Parameters
& Shielding Gases ...................................................................................... 75
Hobart Filler Metals ......................................................................................... 79
Mild & Low Alloy Steel Electrodes ........................................................ 79
Stainless Steel Electrodes ........................................................................ 92
Mild Steel Solid Wires ............................................................................... 95
Tubular Wires ............................................................................................... 99
Metal Cored Wires ....................................................................................109
Hard Surfacing ..........................................................................................113
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Filler Guide for Welding Aluminum .........................................................114
Filler Metal Selector Guide for Welding ASTM Steels ........................115
Welding Terms & Definitions......................................................................136
Metric Conversion Tables ............................................................................140
HIWT Training & Certification Services ...................................................143
HIWT Training Materials...............................................................................144
Index ...................................................................................................................145
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Welding & Cutting Processes
SMAW
Shielded Metal Arc Welding, also called Stick welding and Manual Metal
welding is an electric arc welding process that produces coalescence of
metals by heating them with an arc between a covered consumable metal
electrode and the work. Shielding is obtained from decomposition of
the electrode covering. The process is normally manually applied and is
capable of welding thin and thick steels and some nonferrous metals in all
positions. The process requires a relatively high degree of welder skill.
GMAW
Gas Metal Arc Welding, also known as MIG welding, CO Welding,
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Micro Wire Welding, short arc welding, dip transfer welding, wire weld-
ing, etc., is an electric arc welding process that produces coalescence
of metals by heating them with an arc between a solid, continuous,
consumable electrode and the work. Shielding is obtained from an
externally supplied gas or gas mixture. The process is normally applied
semiautomatically; however, the process may be operated automatically
and can be machine operated. The process can be used to weld thin and
fairly thick steels and some nonferrous metals in all positions. A relatively
low degree of welding skill is required for the process.
FCAW
Flux Cored Arc Welding, also known as Dual-Shielded, Inner-shield, Self
Shield, FabCO, etc., is an electric arc welding process that produces co-
alescence of metals by heating them with an arc between a continuous
flux filled electrode wire and the work. Shielding is obtained through
decomposition of the flux within the tubular wire. Additional shield-
ing may or may not be obtained from an externally supplied gas or gas
mixture. The process is normally applied semi-automatically, but can
be applied automatically or by machine. It is commonly used to weld
medium to thick steels using large diameter electrodes in the flat and hori-
zontal position and small electrode diameters in all positions. The process
is used to a lesser degree for welding stainless steel and for overlay work.
The skill level required for FCAW is similar to GMAW.
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Protective Gas From
Electrode Coating
Molten Weld
Electrode Wire
Metal
Slag
Electrode Coating
Arc
Solidifed
Weld Metal Metal Droplets
Base Metal
Nozzle
Shielding Gas
Electrode
Molten Weld Metal
Solidifed
Arc
Weld Metal
Base Metal
Gas (Optional)
Nozzle (Optional)
Molten Metal
Solidifed
Weld Metal
Molten
Flux Cored
Slag
Electrode
Slag
Arc
Base Metal
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Welding & Cutting Processes
SAW
Submerged Arc Welding, also known as Union Melt, Hidden Arc, Welding
Under Powder, etc., is an arc welding process that produces coalescence
of metals by heating them with an arc or arcs between a bare electrode or
electrodes and the work. The arc is shielded by a blanket of granular flux
on the work. The process is normally applied by machine or automatically,
but is used on a limited basis semi-automatically. It is used to weld medium
to thick steel in the flat and horizontal position only. Manual welding skill
is not required; however, a technical understanding of the equipment and
welding procedures is necessary to operate the process.
GTAW
Gas Tungsten Arc Welding, also known as TIG welding, Heliarc Welding,
Heli-Welding, Argon-Arc Welding and Tungsten Arc Welding, is an electric
arc welding process that produces coalescence of metals by heating them
with an arc between a nonconsumable tungsten electrode and the work.
Filler may or may not be used. Shielding is obtained from an inert gas or an
inert gas mixture. The process is normally applied manually and is capable
of welding steels and nonferrous metals in all positions. The process is com-
monly used on thin metals and for the root and hot pass on tubing and pipe.
Requires a relatively high degree of welder skill.
PAW
Plasma Arc Welding, sometimes referred to as Needle Arc and Micro Plasma, is
an electric arc welding process that produces coalescence of metals by heat-
ing them with a constricted arc between a tungsten electrode and the work
(transferred arc) or the electrode and the constricting nozzle (non-transferred
arc). Shielding is obtained from the hot ionized gas issuing from the orifice.
An auxiliary inert shielding gas or mixture of inert gases may supplement the
system. The process is commonly applied manually, but may be automatic
to increase welding speeds. It can be used to weld almost all metals and
can be all position at lower currents. Normally used on thinner metals, the
process requires a slightly lesser degree of welder skill than Gas Tungsten
Arc Welding, but a greater knowledge of equipment set-up.
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Electorde From Flux
Slag Molten Flux Hopper
Flux Blanket
Solidifed Molten Arc Path Base Metal
Weld Metal Weld Metal
Welding Torch
Shielding Gas
Tungsten Electrode
Molten Weld
Metal
Arc
Solidifed
Weld Metal
Filler Rod
Base Metal
Coolant
Tungsten
Electrode
Orifce to Constrict Arc
Plasma Stream
Shielding Gas
Solidifed Filler Metal
Metal
Base Metal
Molten Weld Metal
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Welding & Cutting Processes
CAW
Carbon Arc Welding, is an electric arc welding process that produces a
coalescence of metals by heating with an arc between a carbon electrode
and the work. No shielding is used. A variation of the process uses two
carbon electrodes with an arc between them. The process is normally ap-
plied manually and is capable of welding thin metals. The process is also
commonly used for brazing. It requires a relatively high degree of welding
skill. This process has limited industrial popularity.
ESW
Electroslag Welding, also known as Porta-Slag or Slag Welding, is a welding
process that produces a coalescence of metals with molten slag which melts
the filler metal and the surface of the work to be welded. The molten weld
pool is shielded by a slag covering which moves along the joint as welding
progresses. The process is not an arc welding process, except that an arc is
used to start the process. After stabilization the molten slag provides the
necessary heat for welding. The process is always applied automatically. It is
a limited application process used only for making vertical welds on medium
to heavy thickness of mild steel. Manual welding skill is not required, but a
techincal knowledge of the process is required to operate the equipment.
EGW
Electrogas Welding, also known as Verti-Matic and Automatic Vertical Airco-
matic, is an arc welding process that produces a coalescence of metals by
heating them with an arc between a continuous filler metal (consumable)
electrode and the work. Molding shoes are used to confine the molten
weld metal for vertical position welding. The electrode may be either flux
cored or solid. Shielding may or may not be obtained from an externally
supplied gas or gas mixture. The process is always applied automatically. It is
a limited application process used only for making vertical welds on medium
to heavy thickness mild steel. Manual welding skills are not required, but
like electroslag welding, a technical knowledge of the process is required
to operate the equipment.
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