NGWA Cable Tool Drilling Exam (A/B) –
Complete Practice Test Bank 2026
Instructions
• Correct Answers are in Bold Italics
• Rationales are in Italic
• Based on NGWA Exam A/B: Cable Tool Drilling certification
requirements
• Covers mechanical principles, components, operational
procedures, and safety protocols
1. In cable tool drilling, what is the "cracker" and what was its
purpose?
A. A steel spring that increased the impact force of the bit
B. A length of manila line used to absorb shock between the tools and the
steel cable
C. A type of fishing tool used to retrieve broken tools
D. A bit designed specifically for drilling through boulders
Correct Answer: B. A length of manila line used to absorb shock
between the tools and the steel cable.
Rationale: Since early derricks were all stiff-legged, a 25-50 foot length of
manila line was placed between the tools and the steel cable to absorb the
shock of the drill tools, preventing damage to the equipment .
,2. Which company bought into the Armstrong Line of Rigs in 1933?
A. Cyclone Manufacturing
B. Bucyrus
C. Keystone Drilling
D. Morgan & Kelly
Correct Answer: B. Bucyrus.
Rationale: Bucyrus bought into the Armstrong Line of Rigs in 1933 and
subsequently changed the name to Bucyrus. This was a significant
consolidation in the cable tool drilling industry .
3. What is the typical role of the pitman arm and crank on a cable tool
rig?
A. To rotate the drill stem
B. To transform rotary motion from the engine into the up-and-down
motion required for percussion drilling
C. To control the bailer's ascent speed
D. To adjust the tension of the wire line
Correct Answer: B. To transform rotary motion from the engine into the
up-and-down motion required for percussion drilling.
Rationale: The pitman arm and crank convert the rotary motion from the
engine into the vertical reciprocating motion needed for percussion drilling .
,4. What was a significant problem with the original straight-thread
joints used on early cable tool drill strings?
A. They were too expensive to manufacture
B. They caused the joints to taper from long, continued use
C. They were incompatible with steel cable
D. They could not be used with the walking beam
Correct Answer: B. They caused the joints to taper from long, continued
use.
Rationale: Drill tool joints were originally made with a straight thread, a
practice which caused these joints to taper from long, continued use. It was
discovered that a tapered joint made a much stronger, secure connection .
5. When did the API standard for cable tool joints become the industry
standard?
A. 1831
B. 1867
C. 1919
D. 1933
Correct Answer: C. 1919.
Rationale: The API thread became the standard in 1919, replacing the earlier
straight-thread joints that caused tapering issues .
6. Who invented the first upper head rubber mounted shock absorber
that eliminated the need for the "cracker"?
, A. Henry Kelly
B. Billy Morris
C. Bud Armstrong
D. O.B. Tanneyhill
Correct Answer: C. Bud Armstrong.
Rationale: Armstrong developed the first upper head rubber mounted shock
absorber that eliminated the "cracker" (the manila line used for shock
absorption). This was a significant advancement in cable tool drilling
technology .
7. What was the name of the company associated with Henry Kelly
when he started selling his portable rigs in 1891?
A. Bucyrus
B. Armstrong Manufacturing Company
C. Armstrong-Quam Co.
D. Morgan, Kelly, and Tanneyhill
Correct Answer: D. Morgan, Kelly, and Tanneyhill.
Rationale: In 1891, Henry Kelly became associated with O.B. Tanneyhill and
they sold rigs under the company name of Morgan, Kelly, and Tanneyhill .
8. What is the primary purpose of a "casing line" on a cable tool rig?
A. To operate the bailer
B. To install and position casing
C. To rotate the drill string
D. To circulate drilling fluid
Complete Practice Test Bank 2026
Instructions
• Correct Answers are in Bold Italics
• Rationales are in Italic
• Based on NGWA Exam A/B: Cable Tool Drilling certification
requirements
• Covers mechanical principles, components, operational
procedures, and safety protocols
1. In cable tool drilling, what is the "cracker" and what was its
purpose?
A. A steel spring that increased the impact force of the bit
B. A length of manila line used to absorb shock between the tools and the
steel cable
C. A type of fishing tool used to retrieve broken tools
D. A bit designed specifically for drilling through boulders
Correct Answer: B. A length of manila line used to absorb shock
between the tools and the steel cable.
Rationale: Since early derricks were all stiff-legged, a 25-50 foot length of
manila line was placed between the tools and the steel cable to absorb the
shock of the drill tools, preventing damage to the equipment .
,2. Which company bought into the Armstrong Line of Rigs in 1933?
A. Cyclone Manufacturing
B. Bucyrus
C. Keystone Drilling
D. Morgan & Kelly
Correct Answer: B. Bucyrus.
Rationale: Bucyrus bought into the Armstrong Line of Rigs in 1933 and
subsequently changed the name to Bucyrus. This was a significant
consolidation in the cable tool drilling industry .
3. What is the typical role of the pitman arm and crank on a cable tool
rig?
A. To rotate the drill stem
B. To transform rotary motion from the engine into the up-and-down
motion required for percussion drilling
C. To control the bailer's ascent speed
D. To adjust the tension of the wire line
Correct Answer: B. To transform rotary motion from the engine into the
up-and-down motion required for percussion drilling.
Rationale: The pitman arm and crank convert the rotary motion from the
engine into the vertical reciprocating motion needed for percussion drilling .
,4. What was a significant problem with the original straight-thread
joints used on early cable tool drill strings?
A. They were too expensive to manufacture
B. They caused the joints to taper from long, continued use
C. They were incompatible with steel cable
D. They could not be used with the walking beam
Correct Answer: B. They caused the joints to taper from long, continued
use.
Rationale: Drill tool joints were originally made with a straight thread, a
practice which caused these joints to taper from long, continued use. It was
discovered that a tapered joint made a much stronger, secure connection .
5. When did the API standard for cable tool joints become the industry
standard?
A. 1831
B. 1867
C. 1919
D. 1933
Correct Answer: C. 1919.
Rationale: The API thread became the standard in 1919, replacing the earlier
straight-thread joints that caused tapering issues .
6. Who invented the first upper head rubber mounted shock absorber
that eliminated the need for the "cracker"?
, A. Henry Kelly
B. Billy Morris
C. Bud Armstrong
D. O.B. Tanneyhill
Correct Answer: C. Bud Armstrong.
Rationale: Armstrong developed the first upper head rubber mounted shock
absorber that eliminated the "cracker" (the manila line used for shock
absorption). This was a significant advancement in cable tool drilling
technology .
7. What was the name of the company associated with Henry Kelly
when he started selling his portable rigs in 1891?
A. Bucyrus
B. Armstrong Manufacturing Company
C. Armstrong-Quam Co.
D. Morgan, Kelly, and Tanneyhill
Correct Answer: D. Morgan, Kelly, and Tanneyhill.
Rationale: In 1891, Henry Kelly became associated with O.B. Tanneyhill and
they sold rigs under the company name of Morgan, Kelly, and Tanneyhill .
8. What is the primary purpose of a "casing line" on a cable tool rig?
A. To operate the bailer
B. To install and position casing
C. To rotate the drill string
D. To circulate drilling fluid
