Explain about types of Operations Scheduling

Various types of Operations Scheduling are:
1. Forward operations scheduling –
a. Classified on the basis of the time.
b. All the activities are scheduled from the date of the planned order release.
c. First task of the job is scheduled.
d. Its subsequent task is scheduled on the scheduled completion of the first task.
e. Like this, accordingly all the tasks of the job are scheduled.

2. Backward operations scheduling –
a. Also classified on the basis of the time.
b. Activities are scheduled from the date or the planned receipt date.
c. The last activity is scheduled first.
d. Time of the start of the last task is considered as the time for the start of the previous activity.

Methods used for the operations scheduling
1. Johnson’s two machine algorithm
a. Very effective when the operations sequencing has two machines and the processing time depends on the sequence in which the jobs are loaded.
b. Also used when the company involves a backlog of the orders.
c. Is a very simple process.
d. Also a time saving process.
e. Helps in the determination of the optimal job sequence.

2. Index method
a. Used for the purpose of the loading and also for allocating the different jobs to the different machines.
b. Generally orders are assigned on the basis of the “first come first assigned” method.
c. But does not provide optimum loading.

3. Critical path analysis
a. Helps in the determination of the scheduling of the activities of the projects.
b. Reveals inter – relationships between the different activities of the project.
c. Reflects the uncertainty in the durations estimated for the various activities.

4. Critical ratio scheduling
a. Helps in the establishment and the maintenance of the priorities among the jobs in a factory.
b. Concept of “critical ratios” is used widely.
c. Helps in the expedition of the functions of the PPC.