1. Define basic size as used with screw threads.

 

2. Define the flank of a thread.

 

3. An American Standard unified thread conforms to the UNR profile. If this is an external thread with 16 threads per inch, what is the depth of the thread?

  

4. A 2-56-UNC-3A thread must be cut on an automatic screw machine. What should the maximum and minimum major diameter be before the screw is threaded?

  

5. A unified thread is designated as a  9/16‑12 UNC‑2A. What is the maximum and minimum pitch diameter?

  

6. A 7/8-27-UNS-2A thread must be checked with a screw pitch micrometer. What should the maximum and minimum pitch diameter be?

 

7. A 1-1/8-16-UN-3A thread must be chased on a lathe. If the shaft has been turned to 1.114", will the part meet the major diameter specifications after the threads have been cut?

  

8. A 2 1/4-10 UNS-2B thread must be chased on a lathe. What are the minor diameter limits that the part must be bored to before threading the part?

 

9.  What is the lead angle a the basic pitch diameter for a 7/16-20 unified screw thread?

 

10. What is the lead angle at the basic pitch diameter for a 2 1/2-4 unified screw thread?

  

11.  What is the minor diameter of a 2 1/2-8 unified internal thread?

 

12.  What is the lead angle at the basic pitch diameter for a 4 1/4-16 unified screw thread?