Republic of the Philippines

DEPARTMENT OF EDUCATION
Region I
Pangasinan Division II
Luciano Millan National High School
Asingan,Pangasinan

MODULE 10
IN
SHIELDED METAL ARC WELDING NC II
Grade 12
(CLEAN SURFACES AND EDGES)
QUARTER II Week 4
OBJECTIVES:
1. Clean surfaces and edges based on the job
requirements.
2. Use correct tools and equipment for cleaning
surfaces and edges in accordance with the job
requirements.
3. Use appropriate Personal Protective Equipment.
4. Perform proper housekeeping (5S).

PREPARED BY:

WILMER J. DIRECTO
SHS-TEACHER

PRE TEST

1
MULTIPLE CHOICE
Directions: Encircle the letter of the correct answer.
1. Why is cleaning of surface and edges of metal so
important?
a. It provides good appearance of the cut material
b.It is given in the instruction.
c. Dirt and other substances are detrimental to weld
quality.
d.d.It makes it easy to fit-up joint.
2 .What tool is used to easily metal scales, old paints
and rust.
a.Grinder b. Scraper
c. Chipping hammer d. Metal sand paper
3 .Why is an air tight fit-up necessary for Tee-joint
preparation?
a. Dirt or contaminant will not stick
b. Gas pockets associated with unfit fit-up are
avoided.
c. Rusting of joint is avoided.
D .None of the above
4 .Beveled joint is considered “critical” in the category
of weld. This means that:
a. Weld joint is necessary for radiography
b. Weld joint is for visual
c.Weld joint needs no inspection
d .All of the above.
5. Root face of beveled joint will not exceed a
maximum of _____
a. 3 mm b. 5 mm c. 3 mm d. 6 mm

6. Bringing an oversized part down to exactdimensions,

2
 removing a hazardous razor edge or burr, and
moothing the ends.
a.Chipping Hammer c. File
b.Sad paper d. Wire brush
7. Primarily an abrasive implement, used for cleaning
rust and removing paint.
a.Grinder c. Sand paper
b.Wire brush d. File
8. Handheld power tool, often used in fabrication and
construction work.
a.Angle grinder c. Bench grinder
b.Belt grinder d. Cylindrical grinder
9. Usually has two wheels of different grain sizes for
roughing and finishing operations and is secured to a
workbench or floor stand.
a.Angle grinder c. Bench grinder
b.Belt grinder d Cylindrical grinder
10. Includes both the types that use centers and the
center less types.
a.Angle grinder c. Bench grinder
b. Belt grinder d. Cylindrical grinder
INFORMATION SHEET 1.1
CLEANING SURFACES AND EDGES OF MATERIALS
Introduction
Proper cleaning of metal surfaces and edges must
be in mind before any fitup and tacking takes place.
There must be an acceptable cleaning procedure
applied in the surface of the plates and pipes before
welding joints. The cleaning of surfaces and edges
is considered one step for achieving quality in the
preparation of materials.

3
 Below are acceptable practices in the preparation of
surfaces and edges of the materials.

Illustration: Figure 1
Edge A needs to grind smoothly and squarely so that
no gaps appear on the fit-up and the surface of the other
plate to form Tee-joint. These two sides of the plate are
placed together to see to it that no gaps are found,then
are tightly assembled. The contaminants that are found
in the fit-up must be cleaned and removed for welding
safety.
Safety measures:
Before tacking, air tight fit-up must be checked so as to
avoid air pockets in the fitted edge or surface.

4
 The drawing showing A and B plates are beveled
cut. The gas cutting results are not properly done, the
surface is not smooth and with irregular line cut caused
by incorrect cutting. The surface must be smoothened
with the use of a grinder until such appearance is
accepted. Dirt and contaminants such as rust, oil,
grease, water, scale and old paint must be removed
from the surface using appropriate tools and solution.
After root face is made and smoothened on the
beveled surface, the two plates are placed together
facing each other with an approximate gap before
tacking may be done. This kind of preparation is
applicable for plates and pipes of different types of
materials. The root face must not exceed the maximum
of 3mm thick from wall thickness of 6mm to 20 mm.

JOINT EDGE PREPARATION

Sheet metal is easily melted and does not require
special edge preparation. In welding operations
involving plate, joint edge preparation and proper
spacing between edges are important factors. The
thickness of the plates determines the amount of edge
preparation required. The faces of square edges can be

5
butted together and welded You can use this type of
joint on plate up to 3/16 of an inch thick. For plate 3/16
to 1/4 of an inch thick, a slight root opening between
the parts is necessary to get complete penetration. Plate
more than 1/4 of an inch thick requires beveled edges
and a root opening of 1/16 of an inch. For oxy gas
welding on plate more than 1/4 of an inch thick, bevel
the edges at an angle of 30 degrees to 45 degrees,
making the groove included angle from 60 degrees to
90 degrees. You can prepare the edges by flame cutting,
shearing, flame grooving, machining, chipping, or
grinding. In any case, the edge surfaces should be free
of oxides, scale, dirt, grease, or other foreign matter.
Plate from 3/8 to 1/2 of an inch thick can be welded
from one side only, but thicker sections should be
welded by preparing the edges on both sides. Generally,
butt joints prepared on both sides permit easier
welding, produce less distortion, and ensure better weld
qualities.
Heavy steel plate is rarely welded with oxy gas unless
other types of welding equipment are not available. The
welding of heavy plate is just not cost effective because
of the amount of gas consumed and time used to
complete a weld. If at all possible, use a form of
electric arc welding because the joint can be welded
faster, cheaper, and there is less heat distortion
Weld Types & Edge Preparations
While designers need some basic knowledge of
welding processes, equipment, materials, and
techniques, their main interest is in how to transfer
forces through welded joints most effectively and
efficiently. Proper joint design is the key to good weld
design.
The loads in a welded-steel design are transferred
from one member to another through welds placed in

6
weld joints. Both the type of joint and the type of weld
are specified by the designer.
So its important for a designer to know what are the
types and edge preparations are possible in each type of
weld. Here they are.

PRE TEST

I-MULTIPLE CHOICE:Directions: Encircle the

letter of the correct answer.
1. Types of joint are formed when two members
intersect at a 90° angle which makes the edges come
together in the center of a plate or component.
a. Tee Joint b. Lap Joint
c. Corner Joint d.Edge Joint
2. Joints are used most often to joint two pieces with
differing thicknesses together.
a. Tee Joint b. Lap Joint
c. Corner Joint d.Edge Joint
3. Joints are often applied to sheet metal parts that have
flanging edges or are placed at a location where a
weld must be made to attach to adjacent pieces.
a. Tee Joint b. Lap Joint
c. Corner Joint d.Edge Joint
4. This weld is a type of joint that comes together at
right angles between two metal parts to form an L.
a. Tee Joint b. Lap Joint
c. Corner Joint d.Edge Joint
5. It consists of two flat pieces that are side by side
parallel.
a. Butt Joint b. Tee Joint
c. Corner Joint d.Edge Joint

The 5 Different Types Of Welding Joints

Tee Joint

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Tee welding joints are formed when two members
intersect at a 90° angle which makes the edges come
together in the center of a plate or component. Tee
Joints are considered a type of fillet weld, and can also
be made when a pipe or tube is welded onto a base
plate. Extra care is required to ensure effective
penetration into the roof of the weld.
Welding Styles Used To Create T-Joints
 Plug weld Fillet weld Bevel-groove weld
Slot weld Flare-bevel-groove weld  J-groove weld
Melt-through weld

Lap Joint
Lap welding joints are used most often to joint two
pieces with differing thicknesses together. Also
considered a fillet type, the weld can be made on one or
both sides. A Lap Joint is formed when 2 pieces are
placed in an over lapping pattern on top of each other.
Welding Styles Used To Create Butt Joints:
1. Slot weld 2. Plug weld 3. Bevel-groove
4. Spot weld 5. Flare-bevel-groove weld 6. J-groove
weld

Edge welding Joints

Edge welding Joints are often applied to sheet metal
parts that have flanging edges or are placed at a location
where a weld must be made to attach to adjacent pieces.
Being a groove type weld, Edge Joints, the pieces are
set side by side and welded on the same edge. For
heavier applications filler metal is added to melt or fuse
the edge completely and to reinforce the plate.
Welding Styles Used To Create Edge Joints:
Bevel-groove weld
Square-groove weld or butt weld
J-groove weld

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V-groove weld
Edge-flange weld
U-groove weld
Corner Welding Joint
Corner Joint
Being one of the most popular welds in the sheet metal
industry the Corner welding joint is used on the outer
edge of the piece. This weld is a type of joint that
comes together at right angles between two metal parts
to form an L. These are common in the construction of
boxes, box frames and similar fabrications.
Welding Styles Used To Create Corner Joints:
Spot weld
Fillet weld
V-groove weld
Square-groove weld or butt weld
U-groove weld
Bevel-groove weld
Flare-V-groove weld
J-groove weld
Corner-flange weld.
Edge weld

Butt Welding Joint

Butt Joint
Being the universally accepted method for attaching a
pipe to itself it’s also used for valves, flanges, fittings,
and other equipment. A butt welding joint is also
known as a square grove weld. It’s the easiest and
probably the most common weld there is. It consists of
two flat pieces that are side by side parallel. It’s a very
affordable option.
Welding Styles Used To Create Butt Joints:
Bevel-groove butt weld

9
Square-groove butt weld
V-groove butt weld
U-groove butt weld
J-groove butt weld
Flare-bevel-groove butt weld

PRE TEST
TRUE OR FALSE.
DIRECTION: Read each statement below carefully.
Write TRUE if the statement is correct and FALSE if
the statement is not correct.
______ 1. In shop safety rules,it should keep all around
tools sharp, clean, and in safe working order.
_______2. The welding machine should be turn on the
power before leaving the school.
_______3. Make sure all guards and barrier are in place
and adjusted properly before starting a
machine tool.
_______4. Operate a hazardous machine only after
receiving instruction or how to operate
the machine safety.
________5. In rules for welding safety it should be
engage in horseplay of any kind.
_______6. The hazards in arc welding can endanger a
welder's life if he/she is not wearing the
proper protective clothing and equipment
________7. Always look out for fellow students and
co-workers.
________8. Never enter the welding shop without
wearing safety glasses.
________9. Wear safety glasses at all times in the shop.
________10. Always make sure ventilation provides
three to four complete changes of air per
hour.

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 Personal Protective Equipment (PPE).
PPE or Personal Protective Equipment is any
clothing, equipment or substance designed to protect a
person from risks of injury or illness.

SAFETY Stare or condition of being safe ,freedom

from danger,risk or injury.
SAFE WELDING PRACTICES
The hazards in arc welding can endanger a welder's life
if he/she is not wearing the proper protective clothing
and equipment
THE ALWAYS RULES FOR WELDING SAFETY
 Always wear suitable protective clothing and eye
protection.
 Always keep a safe, clean work areas.
 Always keep welding equipment in good condition.
 Always check welding areas to make sure they're
safe to work in.
 Always make sure ventilation provides three to four
complete changes of air per hour.
 Always look out for fellow students and co-workers.
THE NEVER RULES FOR WELDING SAFETY
 Never enter the welding shop without wearing safety
glasses.
 Never weld, cut or grind near flammable or explosive
materials.
 Never use oil on gas cylinder, regulators, connections
or hoses.
 Never operate ungrounded equipment.
 Never cut or weld on concrete.
 Never arc weld or operate electrically powered
equipment while standing on wet or damp floors.
 Never cut into barrels, drums, or any container that
has not been purged.
 Never engage in horseplay of any kind.

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EYE SAFETY
 Wear safety glasses at all times in the shop.
 Wear safety glasses and face shield when grinding,
chipping, cutting or shaping metal with any kind of
power tool.
 If you wear contact lenses, check with your doctor to
see if the type of lens you wear requires any special
precautions in the work environment.
 Select proper lens shade for the welding or cutting
activity and make sure the lens is not chipped, cracked
or damaged.
 Do not wear plastic-coated lenses for welding and
cutting.
 Wear welding goggles or a welding hood with the
proper lens shade for all welding and cutting activity.

Basic types of Personal Protective Equipment (PPE)

LEATHER JACKET - is made of chrome leather
and prevents entry of sparks between our clothes and
body.

WELDING CAP - used to protect welders head from

spatters in out position welding or in confined spaces.
WELDING SHIELD/HELMET -It is used to protect
the face and eyes from the arc rays(infrared, ultraviolet
rays) and heat and spatter from the molten metal.
SAFETY GLASSES - are used to protect the eyes
when chipping slag and grinding.
LEATHER GLOVES - made of chrome leather and
protect the welder's hands from heat spatter and
radiation.
WELDING SHOES/LEATHER BOOTS used to
protect our feet from falling spatter, sparks and hot
metals when welding overhead and confined spaces.

12
LEATHER APRON -is made of chrome leather and
provides a welder with complete protection of his chest
to the mid calf from sparks and hot metal.
FACE SHIELD-must also be worn where required
to protect eyes. Welders must wear safety glasses and
chippers and grinders often use face shield in addition
to safety glasses.
LEGGINGS -are made from leather to protect the legs
and feet.
EAR MUFFS -are used for ear coverings and are
connected a flexible band and worn as protection
against extreme noise.

5S System
What is 5S?
It is a systematized approach to organize work areas,
keep rules and standards, and maintain discipline to do
good job.
The practice of 5S develops positive attitude among
workers and cultivates an environment of efficiency,
effectiveness and economy.
It utilizes workplace organization and work
simplification techniques to make work easier, faster,
cheaper, safer and more effective.

Japanese English
Seiri Sort
Seiton Systematize
Seiso Sweep
Seiketsu Standardize
Shitsuke Self-discipline

SEIRI (Sort)
Sort out unnecessary items and dispose them properly.
-Make work easier by eliminating obstacles.

13
-Provide no chance being disturbed by unnecessary
items.
-Eliminate the need to take care of the unnecessary
items.
-Prevents accumulation of unnecessary items.

SEITON (Systematize)
Arrange necessary items in good order so that they
can easily pick for use.
-Classify necessary items into frequency of handling.
-Locate jigs and tools that are used very often near to
the point of use.
-Locate the material at the defined position to ensure
“First-in, Firstout”, as well as to make the work
easy.
-Store and dies molds together with the specific tools
necessary for this set-up.
-Clearly label machinery, equipment parts, jigs, tools
and their locations so that everything is understandable
and visible to everyone at a glance.

SEISO (Sweep)
Clean your workplace completely so that there are no
dust on the floor, machinery and equipment.
-To make the workplace clean, safe and comfortable.
-To make it easy to produce quality products.
-To check whether the machinery and equipment are in
good condition or not.
- responsible persons to each machine, equipment and
area.

SEIKETSU (Standardize)

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 Maintain high standard of workplace organization
and housekeeping at all times.
-To prevent the deterioration of Seiri, Seiton, and Seiso
activities.
-To minimize causes that will make the workplace dirty
and uncomfortable.
-To protect workers from dangerous conditions.
-To make the workers happy and vivid giving them a
chance to present their talent and creativity.

SHITKUSE (Self-discipline)
Do things spontaneously without being told or
ordered.
-Seiri, Seiton, Seiso, Shitsuke, these 4S’s are techniques
and actions to make the workplace well- rganized.
-Shitsuke is a condition in which all members practice
these 4S’s continuously, spontaneously and willingly.
-Shitsuke is the creation of strong cooperation culture
filled with spirit of high productivity through -
implementation of these 4S’s, as well as motivation,
education and training for all the members.
-Management should give good examples.

REFERENCES

15
Welding Technology, Second Edition by Gower A.
Kennedy
Welding Inspection Technology, Education
Department, American welding Society
3.Welding Principles and Application by Larry Jeffus
and Harold V. Johnson
4.https://cliffswelding.com/5-types-welding-joints/
5.CBLM in Welding, TESDA, Philippines

POST TEST

MULTIPLE CHOICE
Directions: Encircle the letter of the correct answer.
1. Why is cleaning of surface and edges of metal so
important?
a. It provides good appearance of the cut material
b.It is given in the instruction.
c. Dirt and other substances are detrimental to weld
quality.
d.d.It makes it easy to fit-up joint.

2 .What tool is used to easily metal scales, old paints

and rust.
a.Grinder b. Scraper
c. Chipping hammer d. Metal sand paper

3 .Why is an air tight fit-up necessary for Tee-joint

preparation?

16
 a.Dirt or contaminant will not stick
b.Gas pockets associated with unfit fit-up are
avoided.
c.Rusting of joint is avoided.
d.None of the above
4 .Beveled joint is considered “critical” in the category
of weld. This means that:
a.Weld joint is necessary for radiography
b.Weld joint is for visual
c.Weld joint needs no inspection
d.All of the above.
5. Root face of beveled joint will not exceed a
maximum of _____
a. 3 mm b. 5 mm c. 3 mm d. 6 mm
6. Bringing an oversized part down to exactdimensions,
removing a hazardous razor edge or burr, and
moothing the ends.
a.Chipping Hammer c. File
b.Sad paper d. Wire brush
7. Primarily an abrasive implement, used for cleaning
rust and removing paint.
a.Grinder c. Sand paper
b.Wire brush d. File
8. Handheld power tool, often used in fabrication and
construction work.
a.Angle grinder c. Bench grinder
b.Belt grinder d. Cylindrical grinder
9. Usually has two wheels of different grain sizes for
roughing and finishing operations and is secured to a
workbench or floor stand.
a.Angle grinder c. Bench grinder
b.Belt grinder d Cylindrical grinder

17
10. Includes both the types that use centers and the
center less types.
a.Angle grinder c. Bench grinder
b. Belt grinder d. Cylindrical grinder

18