Lesson Plan

advertisement
Lesson Plan
Course Title: Flexible Manufacturing
Session Title: Welding Skills
Performance Objective:
After completing this lesson, the student will be able to distinguish between the different
methods of welding and cutting of metal, and demonstrate the basic skills of welding by
producing a set of welding beads and four basic welded joints that match the criteria in the
Welding Project Rubrics.
Specific Objectives:
 Explain the theories of the different kinds of welding and cutting used in flexible
manufacturing industries.
 Safely use the equipment and tools for welding the basic four joints used in welding.
 Explain the difference in oxy/acetylene cutting and plasma cutting.
 Explain the different types of electrodes used in shielded metal arc welding.
 Produce the welding projects.
Preparation
TEKS Correlations:
This lesson, as published, correlates to the following TEKS. Any changes/alterations to the
activities may result in the elimination of any or all of the TEKS listed.
Flexible Manufacturing:

130.327(c)(3)(A)(B)
…demonstrate effective oral and written communication skills with individuals from
varied cultures, including fellow workers, management, and customers;
…appraise blueprints, drawings, charts, diagrams, and welding symbols;

130.327(c)(4)(B)(D)
…examine the theory of shielded metal arc-welding and gas metal arc-welding;
…examine the use of abrasives.

130.327(c)(5)(A)(B)
…safely use hand and power tools and equipment commonly employed in metal
manufacturing;
…properly handle and dispose of environmentally hazardous materials used in metal
manufacturing.

130.327(c)(7)(A)(B)(C)
…examine the cutting processes such as oxy-fuel and plasma;
Copyright © Texas Education Agency, 2012. All rights reserved.
1
…explore the use of the common types of electrodes;
...use various welding machines to weld multiple joints;

130.327(c)(8)(A)
…use mathematics in precision measuring operations;

130.327(c)(9)(A)(B)(C)
…analyze the types, sizes, and properties of sheet metal materials;
…analyze the fundamentals of oxy-fuel processes as related to sheet metal;
…analyze the fundamentals of shielded metal arc-welding as related to sheet metal
under American Welding Society code.

130.327(c)(11)(B)
…construct common sheet metal seams.
Interdisciplinary Correlations:
Geometry:

111.34(b)(6)(A)(B)(C)
…describe and draw the intersection of a given plane with various three-dimensional
geometric figures;
…use nets to represent and construct three-dimensional geometric figures;
…use orthographic and isometric views of three-dimensional geometric figures
to represent and construct three-dimensional geometric figures and solve

111.34(b)(8)(F)
…use conversions between measurement systems to solve problems in real-world
situations.

112.35(c)(1)(A)(B)(C)
...demonstrate safe practices during laboratory and field investigations, including the
appropriate use of safety showers, eyewash fountains, safety goggles, and fire
extinguishers;
…know specific hazards of chemical substances such as flammability, corrosiveness,
and radioactivity as summarized on the Material Safety Data Sheets (MSDS);
…demonstrate an understanding of the use and conservation of resources and the
proper disposal or recycling of materials.

112.35(c)(4)(C)
…compare solids, liquids, and gases in terms of compressibility, structure, shape, and
volume;
Copyright © Texas Education Agency, 2012. All rights reserved.
2
Occupational Correlation (reference: O*Net – www.onetonline.org):
Welders, Cutters, and Welder Fitters 51-4121.06
Similar Job Titles: Welder, Welder-Fitter, Fabricator, Maintenance Welder, Mig Welder, Sub Arc
Operator
Tasks:
 Operate safety equipment and use safe work habits.
 Weld components in flat, vertical, or overhead positions.
 Ignite torches or start power supplies and strike arcs by touching electrodes to metals
being welded, completing electrical circuits.
 Clamp, hold, tack-weld, heat-bend, grind or bolt component parts to obtain required
configurations and positions for welding.
.
Soft Skills: Critical Thinking, Active Listening and Monitoring
Teacher Preparation:
The teacher will need to review the Welding Skills presentation and may want to research
welding inspection on the internet. The Welding Skills, and Welding Skills Matching Terms and
Definitions handouts and Welding Project/Rubrics should be printed. The teacher should have
the equipment and supplies needed for the welding assignment. The teacher should produce
the welding projects to show the students examples of how a weld should appear. The teacher
should be prepared to show an arc welding electrode and the oxy-acetylene torch setup,
welding rods and flux. The teacher should also review the manuals for the equipment in the lab
and may shorten the presentation if lab does not have all the different welding equipment. The
students will need about 3 days to practice welding. This may take some time depending on the
number of welders in the lab.
References:
American Welding Society
• http://www.aws.org
Instructional Aids:
1. Welding Skills presentation
2. Welding Skills Terms handout
3. Welding Skills Matching Terms and Definitions answer key
4. Welding Project/Rubrics handout
Materials Needed:
1. Welding Skills Terms handout for each student
2. Welding Skills Matching Terms and Definitions handout for each student
3. Welding Project/Rubrics handout for each student
5. Scrap metal to practice welding and cutting and to use for the assignments
Copyright © Texas Education Agency, 2012. All rights reserved.
3
Equipment Needed:
1. Computer
2. Data projector
3. Shielded metal arc welding equipment
4. Oxy-fuel welding equipment
5. Oxy-fuel cutting torch
8. Plasma cutter if available
Learner Preparation:
The student should have passed a safety test over the welding equipment and have a parent
permission form turned in.
Introduction
Introduction (LSI Quadrant I):
SAY: Today we are going to discuss the shielded metal-arc welding and oxy-fuel welding.
ASK: During the safety section we reviewed the safety rules for what types of welding?
SHOW: Different welds from both types of welding processes.
SAY: You will have time to practice the different types of welding in this section.
ASK: What is used to cut aluminum? (Allow time to answer.)
SAY: A plasma cutter is used to cut aluminum.
Show: The different types of welders and cutting equipment in the lab.
Outline
Outline (LSI Quadrant II):
Instructors can use the PowerPoint presentation, slides, handouts, and note pages in
conjunction with the following outline.
MI
Outline
Notes to Instructor
I. Welding Skills
A. Information
B. Theory of Shielded Metal Arc-Welding
C. Equipment
Distribute the Welding
Skills Terms handout
and the Welding Skills
Matching Terms and
Definitions handout.
Begin Welding Skills
presentation.
Slides 1-9
The teacher will need
to explain welding and
the theory of arc
welding.
II. Electrode
Slides 9-12
Copyright © Texas Education Agency, 2012. All rights reserved.
4
Information
Classification
Example of Electrode Classification
Electrode Classification Chart
Show an arc welding
electrode. Explain the
meaning of the
numbers printed on
the rod.
III. Fundamentals of Oxy-fuel Welding Process
A. Introduction
B. Fundamentals
C. Equipment
Slides 13-15
Show the oxyacetylene torch setup,
welding rods and flux.
Explain the theory of
oxy-fuel welding
process.
IV. Cutting Processes
A. Plasma cutting
B. Oxygen-acetylene cutting
C. Equipment
Slides 16-20
Explain the differences
in plasma and oxy-fuel
cutting. Let the
students know that
plasma cutting will cut
any material up to 2”
thick and oxy-fuel will
cut any ferrous metal
up to 12” thick.
V. Welding Assignment
A. Assignment
B. Flat plate of beads
C. Four joints
Slides 21-23
Show the students the
welding assignments
and explain the
requirements for
completion.
The students will need
about 3 days to
practice welding. This
may take some time
depending on the
number of welders in
the lab. The
oxy/acetylene torch is
also needed to
practice running beads
with that type of
equipment.
A.
B.
C.
D.
.
Copyright © Texas Education Agency, 2012. All rights reserved.
5
VI. Resource
Verbal
Linguistic
Logical
Mathematical
Visual
Spatial
Slide 25
Musical
Rhythmic
Bodily
Kinesthetic
Intrapersonal
Interpersonal
Naturalist
Existentialist
Application
Guided Practice (LSI Quadrant III):
The teacher will need to monitor the students when starting the welding and cutting processes.
Independent Practice (LSI Quadrant III):
The students will practice running beads until they are ready to turn in the assignment. After
completing the flat plate assignment, the student should weld the four joints and turn this
assignment in for a grade.
Summary
Review (LSI Quadrants I and IV):
Question: What do the first two numbers on an electrode stand for?
Answer: Tensile strength, the amount of pressure that it takes to pull the weld apart
Question: Why is acetylene the usual fuel for oxy-fuel welding and cutting?
Answer: It produces the most (or hottest) heat of the four fuel gasses.
Evaluation
Informal Assessment (LSI Quadrant III):
The students will be monitored during welding. A grade could be assigned for how well the
equipment is used and cleaned up when finished for the class period.
Formal Assessment (LSI Quadrant III, IV):
The flat plate assignment and the four joints assignment will be graded by the Welding
Project/Rubrics.
Copyright © Texas Education Agency, 2012. All rights reserved.
6
Extension
Extension/Enrichment (LSI Quadrant IV):
Students can research weld inspection and testing on the internet and produce a presentation
on weld quality.
Copyright © Texas Education Agency, 2012. All rights reserved.
7
Name __________________________________________Date_______________ Period ____
Welding Skills Terms
Acetylene: a colorless, highly flammable or explosive
gas used for welding
Alternating Current (AC): an electric current that
reverses direction in a circuit at regular intervals
Arc: a flow of electric current across a gap separated between the electrode and
metal
Bead Welding: a deposit of filler metal from a single welding pass
Blacksmith: a person that forges and shapes iron with an anvil and hammer
Brazing: the process of joining two pieces of metal by applying heat and adding a
filler metal; the filler melts at a lower melting point and fills the crack in the metals
Butt Joint: a joint formed by two surfaces placed squarely together
Corner Joint: an L shaped joint formed by two members positioned
perpendicular to each other
Direct Current: an electric current flowing in one direction
Duty Cycle: the time intervals devoted to starting, running, stopping, and idling
when a service is used for intermittent duty
Electrode: in arc welding, the component in a welding circuit through which an
electric current is conducted between the electrode holder and the arc
Flux: a substance applied to the surface to be joined by welding, brazing and
soldering to aide flowing of filler and prevent formation of oxides
Lap Joint: a joint with the ends overlapping
Copyright © Texas Education Agency, 2012. All rights reserved.
8
Welding Skills Terms
Oxy-fuel Welding: the process of using oxygen and a fuel
gas to weld metal
Penetration: the depth of the weld extending into the metal
Plasma Cutting: compressed air is superheated with an electrode; the air turns
into plasma with enough heat to melt and force the metal from the cut
Regulator: a control device designed to maintain a constant flow of substances
Shielded Metal Arc Welding: welding that uses an electric arc to provide heat
Slag: a by-product of welding when impurities in the metal act with flux and rise
to the top of the weld
Tensile Strength: the measurement of the maximum tension the material can
withstand without tearing
T-Joint: a joint between two members which are located approximately at right
angles to each other in the form of a letter T
Welding: joining two or more pieces of metal together along an edge or surface
with heat and a filler material
Copyright © Texas Education Agency, 2012. All rights reserved.
9
Name __________________________________________Date_______________ Period ____
Welding Skills Matching Terms and Definitions
Match the term with the definition.
_____1. Shielded Metal Arc Welding
_____2. Oxy-fuel Welding
_____3. Plasma Cutting
_____4. Oxy-fuel Cutting
A. The use of ionized gas and compressed air to cut
metal.
B. Using an arc of electricity between an electrode and
the metal to be welded to fuse the metal and filler.
C. Using a flame from an oxy-fuel torch to melt the metal
adding a filler rod to the melted puddle to fuse the metal
together.
D. Using an oxy-fuel flame and a blast of oxygen to cut
metal.
Electrode Classification
E6013
Copyright © Texas Education Agency, 2012. All rights reserved.
10
Welding Skills Matching Terms and Definitions
Key
Match the term with the definition.
__B__ 1. Shielded Metal Arc Welding
__C__ 2. Oxy-fuel Welding
__A__3. Plasma Cutting
A. The use of ionized gas and compressed air to cut
metal.
B. Using an arc of electricity between an electrode
and the metal to be welded to fuse the metal and
filler.
C. Using a flame from an oxy-fuel torch to melt the
metal adding a filler rod to the melted puddle to fuse
the metal together.
__D__4. Oxy-fuel Cutting
D. Using an oxy-fuel flame and a blast of oxygen to
cut metal.
Electrode Classification
E = Arc welding electrode
Positions of welding:
1 = all positions (flat, horizontal,
vertical and overhead)
2 = horizontal and flat positions
only
E6013
Tensile strength
first two (or three)
numbers x 1000 or
60 X 1000 = 60,000 psi
power supply
type of coating
polarity
type of arc penetration
Copyright © Texas Education Agency, 2012. All rights reserved.
11
Name __________________________________________Date_______________ Period ____
Welding Project/Rubrics
3 X 3 Flat Plate Assignment:
Number of beads welded ______ X 10 points
_________
Uniformity of beads
max 10 points
_________
Penetration of weld
max 10 points
_________
Overall appearance
max 10 points
_________
Weld Splatter
max 5 points
_________
Grade:
_________
Joint Assignment:
Number of Joints welded ______ X 15 points
_________
Uniformity of beads
max 20 points
_________
Penetration of weld
max 20 points
_________
Overall appearance
max 10 points
_________
Weld Splatter
max 5 points
_________
Grade:
_________
Copyright © Texas Education Agency, 2012. All rights reserved.
12
Download