Q1: Define Turning Center.
Ans: A turning center is a CNC lathe that can perform multiple turning operations automatically with high accuracy.
Q2: Name the types of Turning Center.
Ans: Types of turning centers are:
- ➔ Horizontal Turning Center
- ➔ Vertical Turning Center
- ➔ Double Turret Turning Center
- ➔ Double Chuck Turning Center
- ➔ Universal Turning Center
- ➔ Turning Center with Milling Head Attachment
Q3: What are the main parts of the Turning Center?
Ans: The main parts of a turning center are as follows:
- ➔ Bed
- ➔ Headstock
- ➔ Chuck
- ➔ Tool turret
- ➔ Tailstock
- ➔ Control panel
Q4: Define the Control Axis of the Turning Center.
Ans: Control axes are the directions along which the tool or workpiece moves, usually X-axis and Z-axis.
Q5: What is a Tool Turret?
Ans: A tool turret is a rotating tool holder that automatically selects and holds cutting tools.
Q6: What is a Tailstock?
Ans: A tailstock supports the free end of the workpiece during machining.
Q7: Define Horizontal Turning Center.
Ans: A horizontal turning center has a horizontally mounted spindle and is commonly used for cylindrical parts.
Q8: Define Vertical Turning Center.
Ans: A vertical turning center has a vertically mounted spindle and is used for heavy and large-diameter components.
Q9: Define Double Turret Turning Center.
Ans: A double turret turning center uses two tool turrets to machine a part simultaneously, increasing productivity.
Q10: Define Double Chuck Turning Center.
Ans: A double chuck turning center has two chucks to machine two workpieces or both sides of a workpiece.
Q11: Define Universal Turning Center.
Ans: A universal turning center can perform both turning and limited milling operations.
Q12: Define Turning Center with Milling Head Attachment.
Ans: It is a turning center equipped with a milling head to perform milling along with turning.
Q13: What is Rotary Axis?
Ans: A rotary axis allows rotational movement of the tool or workpiece during machining.
Q14: What is Chuck?
Ans: A chuck is a device used to hold and rotate the workpiece in a turning center.
Q15: Define Tailstock.
Ans: A tailstock is used to support long workpieces and hold tools like drills.
Q16: What is a Machining Center?
Ans: A machining center is a CNC machine capable of performing milling, drilling, boring, and tapping operations.
Q17: Name the types of Machining Center.
Ans: The types of machining centers are as follows:
- ➔ Vertical Machining Center
- ➔ Horizontal Machining Center
- ➔ Double Housing Machining Center
Q18: Define Horizontal Machining Center.
Ans: A horizontal machining center has a horizontal spindle and is suitable for heavy-duty machining.
Q19: Define Vertical Machining Center.
Ans: A vertical machining center has a vertically oriented spindle and is widely used for general machining.
Q20: Define Double Housing Machining Center.
Ans: A double housing machining center has two vertical columns for high rigidity and accuracy.
Q21: Define Saddle.
Ans: A saddle is a supporting structure that allows movement of the table or tool along an axis.
Q22: Define ATC (Automatic Tool Changer).
Ans: ATC is a mechanism that automatically changes cutting tools during machining.
Q23: Define Knee Type Milling Machine.
Ans: A knee type milling machine has an adjustable knee that supports the table.
Q24: Define Bed Type Milling Machine.
Ans: A bed type milling machine has a fixed bed and the table moves along the axes.
Q25: State some operations of the NC Milling Machine.
Ans: The operations of NC milling machine are as follows:
- ➔ Face milling
- ➔ End milling
- ➔ Slot cutting
- ➔ Gear cutting
- ➔ Keyway cutting
Q26: Define Face Milling.
Ans: Face milling produces a flat surface using a rotating cutting tool.
Q27: Define End Milling.
Ans: End milling removes material using the end and sides of the cutter.
Q28: Define Dovetail Cutting.
Ans: Dovetail cutting produces dovetail-shaped slots used in machine slides.
Q29: Define Gear Cutting.
Ans: Gear cutting is the process of machining teeth on a gear blank.
Q30: Define Keyway Cutting.
Ans: Keyway cutting creates a slot in a shaft to hold a key.
Q31: Define Jig-Boring.
Ans: Jig-boring is a precise machining process used to locate and enlarge holes accurately.
Q32: Define NC Hobbing Machine.
Ans: An NC hobbing machine is used to manufacture gears using numerical control.
Q33: Name the gears manufactured by NC Hobbing Machine.
Ans: The gears manufactured by NC hobbing machine are as follows:
- ➔ Spur gears
- ➔ Helical gears
- ➔ Worm gears
- ➔ Sprockets
Q34: Define NC Grinder.
Ans: An NC grinder is a grinding machine controlled by numerical instructions to achieve high precision and surface finish.
Q35: Name the types of NC Grinder.
Ans: The types of NC grinders are as follows:
- ➔ Surface Grinder
- ➔ Cylindrical Grinder
- ➔ CAM Grinder
- ➔ Tool Grinder
Q36: Define Surface Grinder.
Ans: A surface grinder is used to produce a smooth and flat surface on a workpiece.
Q37: Define CAM Grinder.
Ans: A CAM grinder is used to grind cam profiles accurately.
Q38: Define Cylindrical Grinder.
Ans: A cylindrical grinder is used to grind the external or internal cylindrical surfaces of a workpiece.
Q39: What is NC Tool Grinder?
Ans: An NC tool grinder is used to sharpen and manufacture cutting tools with high accuracy.
Q40: Define Flute Angle.
Ans: Flute angle is the angle between the flute and the axis of a cutting tool.
Q41: Define Relief Angle.
Ans: Relief angle is the angle that prevents the tool from rubbing against the workpiece.
Q42: Define Clearance Angle.
Ans: Clearance angle is the angle provided below the cutting edge to reduce friction.
Q43: Define NC Laser Machine Tool.
Ans: An NC laser machine tool uses a laser beam controlled by numerical commands to cut or shape materials.
Q44: Name the types of Lasers.
Ans: The types of lasers are as follows:
- ➔ CO₂ Laser
- ➔ Nd:YAG Laser
- ➔ Fiber Laser
- ➔ Ruby Laser
Q45: Define Laser Processes.
Ans: Laser processes include:
- ➔ Laser cutting
- ➔ Laser drilling
- ➔ Laser welding
- ➔ Laser marking
Q46: Name four advantages of Laser Machines.
Ans: Some of the advantages of laser machines are as follows:
- ➔ High precision
- ➔ No tool wear
- ➔ High cutting speed
- ➔ Clean and accurate cuts
Q47: Name four disadvantages of Laser Machines.
Ans: Some of the disadvantages of laser machines are as follows:
- ➔ High initial cost
- ➔ High power consumption
- ➔ Limited thickness cutting
- ➔ Safety concerns
Q48: Define EDM (Electric Discharge Machining).
Ans: EDM is a machining process that removes material using electrical sparks.
Q49: Name the types of EDM.
Ans: Types of EDM are:
- ➔ Die-sinking EDM
- ➔ Wire Cut EDM
Q50: Define Wire Cut Electric Discharge Machine.
Ans: Wire cut EDM uses a thin wire electrode to cut complex shapes using electric sparks.
Q51: Name the types of Wire Cut Electric Discharge Machine.
Ans: Types of wire cut EDM are:
- ➔ CNC Wire Cut EDM
- ➔ NC Wire Cut EDM
Q52: Define Die-Sinking Electric Discharge Machine.
Ans: Die-sinking EDM removes material by spark erosion using a shaped electrode.
Q53: Define EDM Electrodes Tools.
Ans: EDM electrode tools are conductive materials used to generate sparks for machining.
Q54: Define Dielectric Fluids.
Ans: Dielectric fluids are insulating liquids used in EDM to control sparks and remove debris.
Q55: Name the main parts of the Electric Discharge Machine.
Ans: The main parts of EDM are as follows:
- ➔ Power supply
- ➔ Electrode tool
- ➔ Workpiece
- ➔ Dielectric fluid system
- ➔ Control unit
Q56: Name four advantages of Electric Discharge Machine.
Ans: Some of the advantages of EDM are as follows:
- ➔ Can machine hard materials
- ➔ No cutting force
- ➔ High accuracy
- ➔ Complex shapes possible
Q57: Name four disadvantages of Electric Discharge Machine.
Ans: Some of the disadvantages of EDM are as follows:
- ➔ Slow machining rate
- ➔ High power consumption
- ➔ Electrode wear
- ➔ Limited to conductive materials
Q58: What does LASER stand for?
Ans: LASER stands for Light Amplification by Stimulated Emission of Radiation.
Q59: Why is the cut in the CNC Grinding Machine kept very slow?
Ans: To avoid overheating and to achieve high accuracy and surface finish.
Q60: Briefly write the working of Die-sinking Electric Discharge Machine.
Ans: The working of die-sinking EDM is as follows:
- ➔ Electrode and workpiece are submerged in dielectric fluid
- ➔ Electric sparks remove material
- ➔ Shape of electrode is reproduced on workpiece
Q61: Briefly write the working of Wire Cut Electric Discharge Machine.
Ans: The working of a Wire Cut EDM can be explained step by step:
- ➔ A thin wire acts as the electrode and is positioned close to the workpiece.
- ➔ Controlled electrical sparks are generated between the wire and the workpiece, cutting the material precisely.
- ➔ The wire is continuously fed from a spool to maintain a constant cutting process.
Q62: What is a Driven Tool?
Ans: A driven tool is a rotating tool powered by the machine spindle for milling or drilling.
Q63: State the working principle of the Hobbing Machine.
Ans: Hobbing works on the principle of continuous relative motion between the hob and the workpiece.
Q64: What kind of metals can be cut on an NC Die-sinking Electric Discharge Machine?
Ans: Only electrically conductive metals can be machined.
Q65: What will happen if the wire touches the work-piece during operation in Wire Cut EDM?
Ans: The wire will break due to short circuit.
Q66: What is the voltage consumption of an Electric Discharge Machine?
Ans: An Electric Discharge Machine generally operates at a low voltage range of about 60 to 300 volts.
