Instructor: James Thornburgh Unit 2 Threaded Fasteners Bring up your Homework & Put on Table

Objectives Define keywords related to Threaded Fasteners Define keywords related to Threaded Fasteners List the three classes of fit List the three classes of fit Describe the differences between course, fine, and extra fine threads Describe the differences between course, fine, and extra fine threads Describe the difference between single and multiple thread fasteners Describe the difference between single and multiple thread fasteners List the common information contained in a thread note List the common information contained in a thread note

Objectives List and identify three different methods to graphically represent threads List and identify three different methods to graphically represent threads Identify and draw different types of screws Identify and draw different types of screws Describe the difference between rivets and screws Describe the difference between rivets and screws Draw pipe threads, hex and square bolts and nuts Draw pipe threads, hex and square bolts and nuts Use thread tables to specify or draw threaded fasteners Use thread tables to specify or draw threaded fasteners

What are Threaded Fasteners Screws Screws Terminology Terminology

Thread Forms

Class of fit 1 Loose fit Loose fit For quick assembly For quick assembly 2 High Quality High Quality General purpose General purpose 3 Very High Quality Very High Quality High Precision, stress, or vibration High Precision, stress, or vibration

Thread Pitch Determines how far a Fastener goes with each revolution Determines how far a Fastener goes with each revolution

Thread Notes

Metric Thread Note Pitch is Distance in mm Pitch is Distance in mm

Thread Grades

Thread Table

Drawing Threads Detailed Detailed Show detailed thread form Show detailed thread form Time Consuming Time Consuming Rarely used Rarely used Schematic Schematic Easier than Detailed Easier than Detailed Simplified Simplified Easiest to draw Easiest to draw Used most often Used most often

Pipe Threads Why are they at an angle? Why are they at an angle?

Fastener Types Bolt Bolt Hex or Square Head Hex or Square Head Used with a nut to Squeeze parts Used with a nut to Squeeze parts Stud Stud Threaded into a Part Threaded into a Part Attached second part with a nut Attached second part with a nut Cap Screw Cap Screw Longer than a bolt Longer than a bolt Threaded to the head Threaded to the head Threads into part Threads into part

Fastener Types Cap Screw Cap Screw Can have Socket Head Can have Socket Head Machine Screw Machine Screw Smaller than Cap Screw Smaller than Cap Screw Many different head Styles Many different head Styles Set Screw Set Screw With or without a head With or without a head Used to keep parts still Used to keep parts still

Square Bolt.5” dia Sq Hd Bolt

Hex Bolt 1” dia Hex Hd Bolt

Making Nuts and Bolts Making Nuts and Bolts

Machine Screw Heads

Screw Drive Type

Other Screws Shoulder Shoulder Self Tapping Self Tapping Wood Wood

References

Lab Assignments & Homework Lab Lab Handout Handout Workbook 17.1, 17.2 inst. On Pg 10 Workbook 17.1, 17.2 inst. On Pg 10 Prob 17.2, 17.8 Prob 17.2, 17.8 Homework Homework Chapter Questions 1-17 Chapter Questions 1-17 Online Multiple Choice Quiz Online Multiple Choice Quiz