Republic of the Philippines
Rizal Experimental Station and Pilot
School of Cottage Industries
Jenny's Avenue Ext., Pasig, Metro Manila
3rd Quarter, S.Y. 2017-2018
Shielded Metal Arc Welding NC I
CLASS SCHEDULE:
Monday - Friday
7:00 am - 9:00 am
Grade 9
December 12 and 13, 2017
I. Learning Objectives
At the end of the lesson, the students should be able to;
1. classify the different types of electrode,
2. identify the coatings of electrode,
3. use appropriate Personal Protective Equipment (PPE) ; and,
4. perform proper housekeeping (5S).
II. Subject Matter
A. Electrode Classification
B. References:
Internet
http://www.thefabricator.com/article/arcwelding/vertical-smaw-its-a-stick-up
Book
Fundamental of Arc Welding, Huward Currant, 2015
Welding Skills, 3G E-learning FZLLC 2014. Pg.
III. Materials
A. whiteboard
B. whiteboard marker
C. Visual Aids
D. Welding machine
E. 2pcs. Flat bar 2’’x4’’x6mm
F. E6013 electrode
G. PPE
IV. Procedure
A. Routine Activity
1. Greetings
2. Prayer
3. Checking of Attendance
4. Checking of assignment
5. Review of the past lesson
B. Motivation
To introduce the lesson, the teacher will present different types of electrode.
Learning Content Teaching Teaching Aids
Strategies and Devices
Cellulose-sodium (EXX10): Electrodes of this type cellulosic
material in the form of wood flour or reprocessed low alloy
electrodes have up to30 percent paper. The gas shield
contains carbon dioxide and hydrogen, which are reducing
agents. These gases tend to produce a digging arc that
provides deep penetration. The weld deposit is somewhat
rough, and the spatter is at a higher level than other
electrodes. It does provide extremely good mechanical
properties, particularly after aging. This is one of the
earliest types of electrodes developed, and is widely used
for cross country pipe lines using the downhill welding
technique. It is normally used with direct current with the
electrode positive (reverse polarity).
Cellulose-potassium (EXX11): This electrode is
very similar to the cellulose-sodium electrode, except more
potassium is used than sodium. This provides ionization of
Visual Aids,
the arc and makes the electrode suitable for welding with
Discussion Laptop and
alternating current. The arc action, the penetration, and projector
the weld results are very similar. In both E6010 and E6011
electrodes, small amounts of iron powder may be added.
This assists in arc stabilization and will slightly increase the
deposition rate.
Rutile-potassium (EXX13): This electrode coating is very
similar to the rutile-sodium type, except that potassium is
used to provide for arc ionization. This makes it more
suitable for welding with alternating current. It can also be
used with direct current with either polarity. It produces a
very quiet, smooth running arc.
Low hydrogen-iron powder (EXX28):
This electrode is similar to the EXX18, but has 50 percent or
more iron powder in the coating. It is usable only when welding
in the flat position or for making horizontal fillet welds. The
deposition rate is higher than EXX18. Low hydrogen coatings are
used for all of the higher-alloy electrodes. By additions of
specific metals in the coatings, these electrodes become the
alloy types where suffix letters are used to indicate weld metal
compositions. Electrodes for welding stainless steel are also the
low-hydrogen type.
Storage
Electrodes must be kept dry. Moisture destroys the desirable
characteristics of the coating and may cause excessive spattering
and lead to porosity and cracks in the formation of the welded
area. Electrodes exposed to damp air for more than two or three
hours should be dried by heating in a suitable oven (fig 5-32) for
two hours at 500°F (260°C). After they have dried, they should
be stored in a moisture proof container. Bending the electrode
can cause the coating to break loose from the core wire.
Electrodes should not be used if the core wire is exposed.
Stick Electrodes
Stick welding electrodes vary by:
Size: common
sizes are 1⁄16, 5⁄64, 3⁄32 (most common), 1⁄8, 3⁄16, 7⁄32, 1⁄4, and 5⁄16
inch. Core wire used with electrodes needs to be narrower than
the materials that are welded.
Material: stick welding electrodes come in cast iron, high
carbon steel, mild steel, iron-free (nonferrous) and special
alloys.)
Strength: referred to as tensile strength. Each weld needs to be
stronger than the metal being welded. This means that the
materials in the electrode need to be stronger as well.
Welding position (horizontal, flat etc.): different electrodes are
used for each welding position. Iron powder mix (up to 60% in
flux): iron powder in the flux increases the amount of molten
metal available for the weld (heat turns powder into steel).
Soft arc designation: for thinner metals or for metals that don't
have a perfect fit or gap.
V. Application
3F vertical up, root pass
Materials
4’’x2’’x6mm base metal and E6013 electrode
PPE, A.C. welding machine
Welding Activity Rubrics will be use to evaluate the output.
VI. Generalization
The teacher will ask one students in the class to summarize the lesson.
What are the basic weaving pattern?
What are the uses of weaving?
VII. Evaluation
TEST I: Matching
Instruction. Read the question carefully. Select the best answer in the choices in the box and write it on
the space provided before each number.
Electrode Strength
Coating current
Position rutile
__________1. The "E" stands for arc welding.
__________2. The first two numbers of a 4 digit number and the first 3 digits of a 5 digit number indicate the
minimum tensile (in thousands of pounds per square inch) of the weld that the rod will produce.
__________3. The next to last digit indicates the electrode can be used in.
__________4. The last two digits together, indicate the type of coating on the electrode and the welding the
electrode can be used with.
__________5. The last digit indicates the type of on the electrode.
VIII. Assignment
DIRECTION: Search and define the following terms. Write it in your SMAW notebook.
1. Cellulosic electrode
2. Rutile electrode
References: http://www.weldersuniverse.com/welding_parameters.html
Prepared by: Checked By:
Ryan V. Munar, BTTE IV-ST MR. MARVIN S. TIANGSON
Student Teacher Cooperating Teacher
Mr. Roberto M. Melad
Head Teacher III, TVE/TVL
