Transcript Week 2 GD&T - itt.3d-me

Unit 2
Threaded Fasteners
Instructor:
James Thornburgh
Bring up your Homework & Put on Table
Objectives
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Define keywords related to Threaded Fasteners
List the three classes of fit
Describe the differences between course, fine,
and extra fine threads
Describe the difference between single and
multiple thread fasteners
List the common information contained in a
thread note
Objectives
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List and identify three different methods to
graphically represent threads
Identify and draw different types of screws
Describe the difference between rivets and
screws
Draw pipe threads, hex and square bolts and
nuts
Use thread tables to specify or draw threaded
fasteners
What are Threaded Fasteners
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Screws
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Terminology
Thread Forms
Class of fit
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1
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2
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Loose fit
For quick assembly
High Quality
General purpose
3
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Very High Quality
High Precision, stress, or vibration
Thread Pitch
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Determines how far a Fastener goes with
each revolution
Thread Notes
Metric Thread Note
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Pitch is Distance in mm
Thread Grades
Thread Table
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http://www.littlemachineshop.com/Reference/tapdrill.php
Drawing Threads
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Detailed
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Schematic
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Show detailed thread form
Time Consuming
Rarely used
Easier than Detailed
Simplified
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Easiest to draw
Used most often
Pipe Threads
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Why are they at an angle?
Fastener Types
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Bolt
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Stud
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Hex or Square Head
Used with a nut to
Squeeze parts
Threaded into a Part
Attached second part
with a nut
Cap Screw
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Longer than a bolt
Threaded to the head
Threads into part
Fastener Types
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Cap Screw
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Machine Screw
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Can have Socket Head
Smaller than Cap
Screw
Many different head
Styles
Set Screw
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With or without a head
Used to keep parts still
Square Bolt
.5” dia Sq Hd Bolt
Hex Bolt
1” dia Hex Hd Bolt
Making Nuts and Bolts
Machine Screw Heads
Screw Drive Type
Other Screws
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Shoulder
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Self Tapping
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Wood
References
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http://www.mcmaster.com
http://www.boltscience.com/
http://www.Barnhillbolt.com
http://www.fastenal.com
Lab Assignments & Homework
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Lab
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Handout
Workbook 17.1, 17.2 inst. On Pg 10
Prob 17.2, 17.8
Homework
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Chapter Questions 1-17
Online Multiple Choice Quiz