Chapter 5, Problem 11A

This casting in Figure 5-4 shows seven tapped holes, A-G. The number of threads is determined by dividing the depth of the thread by the thread pitch. Find the number of threads in each of the tapped holes. All dimensions are in inches.

   $\begin{array}{l}\text{A}=\underset{\_}{}\\ \text{B}=\underset{\_}{}\\ \text{C}=\underset{\_}{}\\ \text{D}=\underset{\_}{}\\ \text{E}=\underset{\_}{}\\ \text{F}=\underset{\_}{}\\ \text{G}=\underset{\_}{}\end{array}$

To determine

(a)

Evaluate the number of threads for hole A.

Answer to Problem 11A

The number of threads for hole A is $6$.

Explanation of Solution

Given:

All the dimensions are shown below:

  

Concept used:

Divide the depth by pitch of threads.

Calculation:

Divide the depth $\frac{1}{2}$ by pitch of threads $\frac{\text{1}}{12}$ as follows:

  $\begin{array}{l}x=\frac{1}{2}÷\frac{1}{12}\\ x=\frac{1}{2}\times 12\\ x=6\end{array}$

Thus, the number of threads for hole A is $6$.

Conclusion:

The number of threads for hole A is $6$.

To determine

(b)

Evaluate the number of threads for hole B.

Answer to Problem 11A

The number of threads for hole B is $8\frac{7}{16}$.

Explanation of Solution

Given:

All the dimensions are shown below:

  

Concept used:

Divide the depth by pitch of threads.

Calculation:

Divide the depth $\frac{15}{16}$ by pitch of threads $\frac{\text{1}}{9}$ as follows:

  $\begin{array}{l}x=\frac{15}{16}÷\frac{1}{9}\\ x=\frac{15}{16}\times \frac{9}{1}\\ x=\frac{135}{16}\\ x=8\frac{7}{16}\end{array}$

Thus, the number of threads for hole B is $8\frac{7}{16}$.

Conclusion:

The number of threads for hole B is $8\frac{7}{16}$.

To determine

(c)

Evaluate the number of threads for hole C.

Answer to Problem 11A

The number of threads for hole C is $3\frac{1}{2}$.

Explanation of Solution

Given:

All the dimensions are shown below:

  

Concept used:

Divide the depth by pitch of threads.

Calculation:

Divide the depth $\frac{1}{4}$ by pitch of threads $\frac{\text{1}}{14}$ as follows:

  $\begin{array}{l}x=\frac{1}{4}÷\frac{1}{14}\\ x=\frac{1}{4}\times \frac{14}{1}\\ x=\frac{7}{2}\\ x=3\frac{1}{2}\end{array}$

Thus, the number of threads for hole C is $3\frac{1}{2}$.

Conclusion:

The number of threads for hole C is $3\frac{1}{2}$.

To determine

(d)

Evaluate the number of threads for hole D.

Answer to Problem 11A

The number of threads for hole D is $7$.

Explanation of Solution

Given:

All the dimensions are shown below:

  

Concept used:

Divide the depth by pitch of threads.

Calculation:

Divide the depth $\frac{7}{8}$ by pitch of threads $\frac{\text{1}}{8}$ as follows:

  $\begin{array}{l}x=\frac{7}{8}÷\frac{1}{8}\\ x=\frac{7}{8}\times \frac{8}{1}\\ x=7\end{array}$

Thus, the number of threads for hole D is $7$.

Conclusion:

The number of threads for hole D is $7$.

To determine

(e)

Evaluate the number of threads for hole E.

Answer to Problem 11A

The number of threads for hole E is $6\frac{7}{8}$.

Explanation of Solution

Given:

All the dimensions are shown below:

  

Concept used:

Divide the depth by pitch of threads.

Calculation:

Divide the depth $\frac{5}{8}$ by pitch of threads $\frac{\text{1}}{11}$ as follows:

  $\begin{array}{l}x=\frac{5}{8}÷\frac{1}{11}\\ x=\frac{5}{8}\times \frac{11}{1}\\ x=\frac{55}{8}\\ x=6\frac{7}{8}\end{array}$

Thus, the number of threads for hole E is $6\frac{7}{8}$.

Conclusion:

The number of threads for hole E is $6\frac{7}{8}$.

To determine

(f)

Evaluate the number of threads for hole F.

Answer to Problem 11A

The number of threads for hole F is $6\frac{1}{2}$.

Explanation of Solution

Given:

All the dimensions are shown below:

  

Concept used:

Divide the depth by pitch of threads.

Calculation:

Divide the depth $\frac{13}{32}$ by pitch of threads $\frac{\text{1}}{16}$ as follows:

  $\begin{array}{l}x=\frac{13}{32}÷\frac{\text{1}}{16}\\ x=\frac{13}{32}\times \frac{16}{1}\\ x=\frac{13}{2}\\ x=6\frac{1}{2}\end{array}$

Thus, the number of threads for hole F is $6\frac{1}{2}$.

Conclusion:

The number of threads for hole F is $6\frac{1}{2}$.

To determine

(g)

Evaluate the number of threads for hole G.

Answer to Problem 11A

The number of threads for hole G is $2\frac{13}{16}$.

Explanation of Solution

Given:

All the dimensions are shown below:

  

Concept used:

Divide the depth by pitch of threads.

Calculation:

Divide the depth $\frac{9}{16}$ by pitch of threads $\frac{\text{1}}{5}$ as follows:

  $\begin{array}{l}x=\frac{9}{16}÷\frac{\text{1}}{5}\\ x=\frac{9}{16}\times \frac{5}{1}\\ x=\frac{45}{16}\\ x=2\frac{13}{16}\end{array}$

Thus, the number of threads for hole G is $2\frac{13}{16}$.

Conclusion:

The number of threads for hole G is $2\frac{13}{16}$.