MODELS FOR PRACTICE IN WORK SHOP | : TURNING PRACTIC -24 Hrs | DIPLOMA

MODELS FOR PRACTICE IN WORK SHOP                

UNIT I: TURNING PRACTIC -24 Hrs (NOTE: INDIVIDUAL MODEL)

 

1.   To make the part shown in the sketch from a mild steel rod on a Lathe


EQUIPMENT: List all tools and instruments used.

OUTLINE OF PROCEDURE

Hold the bar in a three jaw chuck and face the end with a right hand facing tool. Make central hole with a center drill. Repeat these' operations for the other end of the bar. Replace the chuck by a dog plate (Center plate) and hold the job in a carrier between centers. Turn the bar to the required diameter with rough cuts. Face the steps and finishes the diameters to the required sizes. Machine the roots and the groove with form tools. Machine the taper with the help of the cross-slide swiveling arrangement. Knurl the required surface. Cut the threads.

OBSERVATIONS

(a)                 Measure all dimensions (up to second decimal place) on the specimen turned by your group. Make a neat sketch and indicate all measured dimensions.

(b)              Discuss briefly how tapered portion was turned.

(c)              Show the calculation of the required gear ratio for thread cutting.

(d)              Sketch the main drive unit of 'the- lathe and show how the speed steps are obtained.

 

UNTII: DRILLING PRACTICE                                    -12Hrs (NOTE: INDIVIDUAL MODEL)

Text Box: UNTII: DRILLING PRACTICE	12Hrs


2.   To drill, file, as shown in the sketch, out of the work piece provided and tap holes on

the mild steel plate.)


 

 

OBJECTIVE: To study the characteristic features of Drilling machine.

 

OUTLINE OF PROCEDURE

i)  Run the machine at low speed and observe the motions, which control the shapes of the surfaces produced. Note particularly the features, which control the geometrical form of the surface.

 

ji) Learn the names of the major units and the components of each machine. Record these details (Table A). (Please ensure that the main isolator switch is off and check that the machine cannot be inadvertently started. Do not remove guards). Use the manufacture's handbook for details that cannot be inspected.

 

jii) Record the obtainable speed and feed values

 

iv)  Note down the special features of the speed and feed control on each machine,

 

v)  Pay attention to the following:

a, Size specification of various machine tools,

b, Machine tool structures and guide ways I slide ways.

b. Drive mechanism for primary (cutting) motion,

c. Drive mechanism for secondary (feed) motion.


UNIT III: SHAPING PRACTICE -12Hrs (NOTE:ONE MODEL FOR GROUP OF 05 STUDENTS)

 

3.   To machine a V-block as shown in the sketch out of the work piece provided.