Podcast
Questions and Answers
The major diameter is the ________ diameter of the thread.
The major diameter is the ________ diameter of the thread.
largest
The minor diameter is the ________ diameter of the thread.
The minor diameter is the ________ diameter of the thread.
smallest
The units of pitch are mm or inches per _______________.
The units of pitch are mm or inches per _______________.
thread
What are the two most common thread forms?
What are the two most common thread forms?
Signup and view all the answers
External threads may be cut using a ________.
External threads may be cut using a ________.
Signup and view all the answers
Internal thread may be cut using a _________.
Internal thread may be cut using a _________.
Signup and view all the answers
A tap drill is used when manufacturing _____________ threads.
A tap drill is used when manufacturing _____________ threads.
Signup and view all the answers
In the thread notation 1/4 - 20 UNC, what is 20?
In the thread notation 1/4 - 20 UNC, what is 20?
Signup and view all the answers
In the thread notation 1/2 - 13 UNC, what is UN?
In the thread notation 1/2 - 13 UNC, what is UN?
Signup and view all the answers
In the thread notation 3/8 - 24 UNF, what is F?
In the thread notation 3/8 - 24 UNF, what is F?
Signup and view all the answers
In the notation 5/8 - 24 UNEF -- 2A - RH, what is 2?
In the notation 5/8 - 24 UNEF -- 2A - RH, what is 2?
Signup and view all the answers
In the notation 1 - 8 UNC -- 3B - RH, what is B?
In the notation 1 - 8 UNC -- 3B - RH, what is B?
Signup and view all the answers
In the notation 1/2 - 20 UNF -- 2B - LH, what is LH?
In the notation 1/2 - 20 UNF -- 2B - LH, what is LH?
Signup and view all the answers
In the notation #10 - 24 UNC, what is #10?
In the notation #10 - 24 UNC, what is #10?
Signup and view all the answers
In the notation M5 x 0.8, M stands for ______________.
In the notation M5 x 0.8, M stands for ______________.
Signup and view all the answers
In the notation M4 x 0.7, what is 4?
In the notation M4 x 0.7, what is 4?
Signup and view all the answers
In the notation M12 x 1.25, what is 1.25?
In the notation M12 x 1.25, what is 1.25?
Signup and view all the answers
In the notation M6 x 1 -- 4h6h -- RH, what is 4h6h?
In the notation M6 x 1 -- 4h6h -- RH, what is 4h6h?
Signup and view all the answers
Which one is the fine thread in M20 x 2.5 and M20 x 1.5?
Which one is the fine thread in M20 x 2.5 and M20 x 1.5?
Signup and view all the answers
The schematic thread symbol draws lines at every crest and _______________.
The schematic thread symbol draws lines at every crest and _______________.
Signup and view all the answers
The simplified thread symbol uses a _____________ line to represent the minor diameter on external threads.
The simplified thread symbol uses a _____________ line to represent the minor diameter on external threads.
Signup and view all the answers
How much longer is the tap drill depth than the thread depth when using a taper tap?
How much longer is the tap drill depth than the thread depth when using a taper tap?
Signup and view all the answers
The tap drill diameter is closest in size to the __________ diameter.
The tap drill diameter is closest in size to the __________ diameter.
Signup and view all the answers
A bolt or screw clearance hole diameter depends on what factors?
A bolt or screw clearance hole diameter depends on what factors?
Signup and view all the answers
A standard parts sheet contains enough information about the standard parts so that they may be...
A standard parts sheet contains enough information about the standard parts so that they may be...
Signup and view all the answers
A standard parts sheet contains drawings of all purchased parts.
A standard parts sheet contains drawings of all purchased parts.
Signup and view all the answers
Study Notes
Thread Characteristics
- Major diameter refers to the largest diameter of a thread.
- Minor diameter indicates the smallest diameter of a thread.
Thread Measurement Units
- Pitch is measured in either millimeters or inches per thread.
Common Thread Forms
- Two most frequent thread forms are unified and metric screw threads.
Thread Cutting Techniques
- External threads can be cut using a die or lathe.
- Internal threads are created with a tap.
- A tap drill is essential for manufacturing internal threads.
Unified National Thread Designations
- In 1/4 - 20 UNC, "20" signifies 20 threads per inch, resulting in a pitch of 1/20.
- "UN" in 1/2 - 13 UNC indicates it is a Unified National thread form.
- In 3/8 - 24 UNF, "F" denotes fine thread series.
Thread Classes and Types
- In 5/8 - 24 UNEF -- 2A - RH, "2" denotes a thread class for normal production fit.
- "B" in 1 - 8 UNC -- 3B - RH represents internal threads.
- "LH" in 1/2 - 20 UNF -- 2B - LH indicates left-handed threads.
- "#10" in #10 - 24 UNC corresponds to the major diameter.
Metric Thread Designations
- "M" in M5 x 0.8 signifies a metric thread form.
- The number "4" in M4 x 0.7 reflects the major diameter.
- In M12 x 1.25, "1.25" indicates pitch, which is 1.25 mm per thread.
- "4h6h" in M6 x 1 -- 4h6h -- RH represents the tolerance class.
- M20 x 1.5 is identified as a fine thread in comparison to M20 x 2.5.
Thread Symbolization
- The schematic thread symbol includes lines drawn at both the crest and the root of the thread.
- Simplified thread symbols employ a hidden line to depict the minor diameter on external threads.
Tap Drill and Clearance Hole Specifications
- When using a taper tap, the tap drill depth extends 3 times the pitch beyond the thread depth.
- The tap drill diameter closely matches the minor diameter of the thread.
- The clearance hole diameter for bolts or screws depends on the major diameter and the desired fit.
Standard Parts Sheet
- Standard parts sheets include sufficient information for purchasing standard parts.
- It is incorrect to claim that these sheets contain drawings of all purchased parts.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
Test your knowledge of threads and fasteners with these 15 flashcards. Each card covers key terms and definitions, helping you to master the concepts of thread diameters, pitch, and common thread forms. Perfect for students and professionals alike.
