1. With the use of Jigs and fixtures total cost of production
a) Increases
b) Decreases
c) Remains same
d) Jigs are not used in any production process
Answer: b
Explanation: Total cost of production decreases with the use of jigs and fixture, because with the help of Jigs and fixtures we can hold or unhold any workpiece very easily in less time.
2. With the use of Jigs and fixture rate of production will
a) Increase
b) Decrease
c) Remains same
d) Jigs are not used in any production process
Answer: a
Explanation: Total production increase with the use of jigs and fixture, because with the help of Jigs and fixtures we can hold or unhold any workpiece very easily in less time.
3. Jigs and fixture increases the accuracy of the parts.
a) True
b) False
Answer: a
Explanation: Accuracy of parts increases by use of jigs and fixture, because with the help of jigs and fixtures we can hold any work accurately and guide the tool also.
4. With the use of Jigs and fixtures quality control expenses will
a) Reduce
b) Increases
c) Jigs and fixture are not used in any production process
d) None of the mentioned
Answer: a
Explanation: Jigs and fixture increase accuracy. So the quality control expense will reduce.
5. With the use of Jigs and fixtures
a) Labour cost decreases
b) Labour cost increases
c) Labour cost remains same
d) None of the mentioned
Answer: a
Explanation: Less skilled labour required. So labour cost decreases.
6. Which of the following is not correct about fixture?
a) It is used to hold the work
b) It is used to position the work
c) It assures high accuracy of parts
d) It is used to guide the cutting tool
Answer: d
Explanation: Fixtures do not guide cutting tool. Jigs guide the tool.
7. Which of the following is not correct about jig?
a) It is used to hold the work
b) It is used to position the work
c) It is used to guide the cutting tool
d) None of the mentioned
Answer: d
Explanation: All of the mentioned are correct about jigs, i.e. jig guides the tool, holds the work in correct position.
8. In which of the following operation jigs are preferred over fixture?
a) Drilling
b) Turning
c) Milling
d) Grinding
Answer: a
Explanation: Jigs are preferred over fixtures in drilling because they also help in guidance of tool.
9. Jigs and Fixtures are used for
a) Mass production
b) Identical parts production
c) Both a and b
d) None of the above
Answer: c
Explanation: Jigs & fixtures are only used for mass & batch production.
10. The following holds the workpiece securely in a jig or fixture against the cutting forces.
a) Locating device
b) Clamping device
c) Guiding device
d) Indexing device
Answer: b
Explanation: Among the four options, only clamping device is a work holding device.
11. The following type of jig is used for machining in more than one plane.
a) Template jig
b) Plate type jig
c) Open type jig
d) Box type jig
Answer: d
Explanation: Among the four options, only box jig has more than one machining face.
12. Jigs and fixtures are
a) Machining tools
b) Precision tools
c) Both a and b
d) None of the above
Answer: d
Explanation: Jigs & fixtures are work holding & tool guiding device.
13. Fixtures are used in connection with
a) Drilling operation
b) Reaming operation
c) Tapping operation
d) Milling operation
Answer: d
Explanation: Jigs are used for drilling, reaming & tapping operation & fixtures are used for milling operation.
14. In the context of machining, what is a "template" often used for in a jig?
a. Tool alignment
b. Workpiece clamping
c. Material measurement
d. Chip removal
Answer: a
Explanation: The purpose of jig is to guide the tool & template is one type of jig.
15. Which of the following is a key difference between a jig and a fixture?
a. Jigs are stationary, while fixtures are movable
b. Jigs are used for milling, while fixtures are used for turning
c. Jigs guide the tool, while fixtures hold the workpiece
d. Fixtures guide the tool, while jigs hold the workpiece
Answer: c
Explanation: The purpose of jig is to guide the tool & hold the workpiece & the purpose of fixture is to rigidly hold the workpiece.
16. The primary purpose of a jig is:
(a) To locate and hold a workpiece during an operation
(b) To increase production speed
(c) To improve the surface finish of the workpiece
(d) To reduce operator fatigue
Answer: a
Explanation: Jigs are primarily positioning devices that ensure accuracy and repeatability by rigidly holding the workpiece during machining, drilling, or other operations. While jigs may indirectly contribute to production speed and reduced fatigue, those are not their primary functions.
17. A fixture differs from a jig in that:
(a) It is used for assembly operations only
(b) It allows for greater workpiece movement during machining
(c) It is typically more complex and permanent
(d) It provides no locating surfaces for the workpiece
Answer: c
Explanation: Both jigs and fixtures hold and locate workpieces, but fixtures are generally more complex and designed for specific operations or assemblies. Jigs tend to be simpler and are often specific to a single hole or process. Fixtures may be permanent fixtures in a production line, while jigs are often more portable.
18. The benefits of using jigs and fixtures include:
(a) Increased accuracy and repeatability
(b) Reduced setup time and labour costs
(c) Improved safety for operators
(d) All of the above
Answer: d
Explanation: Increased accuracy and repeatability are primary benefits of using jigs and fixtures, as they ensure consistent positioning and reduce operator error. They also reduce setup time and labour costs due to faster workpiece handling and simplified processes. Additionally, properly designed jigs and fixtures can improve operator safety by minimizing the need for manual tool manipulation near cutting tools.
19. The materials commonly used for making jigs and fixtures include:
(a) Mild steel, cast iron, aluminium
(b) Plastics, wood, composites
(c) Tool steel, carbide, diamond
(d) Any of the above depending on application
Answer: d
Explanation: The choice of material depends on the specific application and required strength, rigidity, weight, and cost constraints. Mild steel, cast iron, and aluminium are common for light-duty jigs and fixtures. Plastics and wood are sometimes used for temporary jigs or when low cost is a priority. Tool steel, carbide, and diamond are used for high-precision and wear-resistant applications.
20. Which of the following types of jigs is most suitable for mass production?
(a) Universal jig
(b) Special purpose jig
(c) Template jig
(d) Bush plate jig
Answer: b
Explanation: Special purpose jigs are designed for a specific workpiece
and operation, maximizing accuracy and efficiency for high-volume production. Universal jigs offer some adaptability, but at the cost of precision and speed compared to dedicated jigs. Template jigs and bush plate jigs are less common and have specific applications.
21. The clamping mechanism in a jig or fixture should be:
(a) As simple as possible
(b) Capable of applying uniform pressure
(c) Easily adjustable for different workpiece sizes
(d) All of the above
Answer: d
Explanation: A good clamping mechanism should be simple to operate, apply uniform pressure without distortion, and allow for adjustments to accommodate different workpiece sizes or variations.
22. Which of the following is NOT a common type of locating element in jigs and fixtures?
(a) V-block
(b) Pin and bushing
(c) Clamp
(d) Stop gauge
Answer: c
Explanation: While clamps are used indirectly to secure the workpiece,
they are not considered locating elements that directly position the workpiece for machining or assembly. V-blocks, pins and bushings, and stop gauges are common types of locating elements that define the precise placement of the workpiece.
23. The design of a jig or fixture should consider the:
(a) Sequence of operations
(b) Ease of loading and unloading
(c) Accessibility of cutting tools
(d) All of the above
Answer: d
Explanation: A well-designed jig or fixture should consider the sequence of operations to ensure efficient workflow. Ease of loading and unloading helps minimize setup time and operator fatigue. Accessibility of cutting tools allows for proper tool movement and ensures worker safety.
24. Which of the following statements is TRUE about drill jigs?
(a) They are typically used for machining external surfaces
(b) They often incorporate guide bushings for drills
(c) They usually require multiple setups for different hole locations (d) They are not suitable for high-precision drilling
Answer: b
Explanation: Drill jigs are specifically designed for drilling operations and typically utilize guide bushings that precisely position the drill bit relative to the workpiece. While they can be used for machining external surfaces with additional features, their primary function is focused on accurate drilling.
25. What is the main disadvantage of using universal jigs?
(a) They are expensive to manufacture
(b) They are less accurate than special purpose jigs
(c) They are not as versatile as other types of jigs
(d) They require more setup time
Answer: b
Explanation: Universal jigs offer some versatility by accommodating different workpieces, but their adaptability often comes at the expense of precision. Compared to special purpose jigs designed for a specific task, universal jigs may have inherent tolerances or require more careful setup to achieve the desired accuracy.
26. Which of the following is NOT a factor to consider when selecting a material for a jig or fixture?
(a) Strength and rigidity
(b) Cost
(c) Weight
(d) Wear resistance
Answer: d
Explanation: While wear resistance is an important consideration for
materials used in jigs and fixtures, it's not the only factor. Strength, rigidity, cost, and weight all play crucial roles in selecting the appropriate material for the specific application and expected loads.
27. What is the purpose of using jigs and fixtures in assembly operations?
(a) To hold components in place during welding
(b) To ensure accurate alignment of components
(c) To increase the speed of assembly
(d) All of the above
Answer: d
Explanation: Jigs and fixtures in assembly operations are used to hold
components in place during welding, ensure accurate alignment for bolting or other joining methods, and ultimately increase the speed and efficiency of the assembly process.
28. What type of fixture is commonly used for welding operations?
(a) Positioner
(b) Clamping fixture
(c) Indexing fixture
(d) Assembly fixture
Answer: a
Explanation: Welding positioners are essentially large fixtures that manipulate and hold workpieces in various positions for optimal welding access and quality. Clamping fixtures, indexing fixtures, and assembly fixtures are more commonly used for other types of assembly processes.
29. How can jigs and fixtures be designed to improve operator safety?
(a) By incorporating interlocks and guards
(b) By using quick-release mechanisms
(c) By designing them for ergonomic use
(d) All of the above
Answer: d
Explanation: Incorporating interlocks and guards can prevent accidental operation or contact with moving parts. Quick-release mechanisms allow for faster loading and unloading, reducing operator exposure to potential hazards. Designing jigs and fixtures for ergonomic use minimizes awkward postures and reduces the risk of musculoskeletal injuries.
30. What is the importance of proper maintenance of jigs and fixtures?
(a) To ensure accuracy and repeatability
(b) To prevent accidents and injuries
(c) To extend their service life
(d) All of the above
Answer: d
Explanation: Proper maintenance of jigs and fixtures ensures accuracy and repeatability by preventing wear and tear that could affect positioning and dimensions. Regular maintenance also identifies potential damage or worn-out components that could lead to accidents or injuries. Maintaining jigs and fixtures extends their service life and reduces the need for frequent replacements, saving costs in the long run.
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