Mumbai University > Mechanical Engineering > Sem 7 > Production planning and control

Marks: 10M

Year: Dec 2015

Planning is the determinative phase of production management. It “figures out” what is to be done. Production planning translates sales forecasts into master production schedules, takes off material, personnel & equipment requirements & prepares detailed area or department schedules.

• It also determines the maintaining of raw materials & finished goods at proper levels. Also, it prepares alternative plans of action as a means of meeting emergencies.
• Control balances production & inventories apart from the determinative phase of planning. Production control supervises the execution of production schedules so that work flows through the manufacturing departments on time & without interruptions.
• Control also maintains raw material inventories at levels that neither tie-up excessive amounts of working capital nor lead to shortages that interrupt production. At the same time, finished goods inventories are regulated so that they neither become excessive nor fall so low that they fail to meet demands & so cause back orders to accumulate

Functions/scope of production planning & control

Production planning

• Production planning may be defined as the technique of foreseeing every step in a long series of separate operations, each step to be takenat the right time and in the right place and each operation to be performed inmaximum efficiency.
• It helps entrepreneur to work out the quantity of materialmanpower, machine and money requires for producing predetermined level of output in given period of time

Routing:

• Under this, the operations, their path and sequence are established. To perform these operations the proper class of machines and personnel required arealso worked out.
• The main aim of routing is to determine the best and cheapest sequence of operations and to ensure that this sequence is strictly followed.

• Insmall enterprises, this job is usually done by entrepreneur himself in a rather adhoc manner. Routing procedure involves following different activities

  • An analysis of the article to determine what to make and what to buy.
  • To determine the quality and type of material
  • Determining the manufacturing operations and their sequence.
  • A determination of lot sizes
  • Determination of scrap factors
  • An analysis of cost of the article
  • Organization of production control forms.

Scheduling:

• It means working out of time that should be required to perform eachoperation and also the time necessary to perform the entire series as routed, making allowances for all factors concerned.
• It mainly concerns with timeelement and priorities of a job. The pattern of scheduling differs from one job toanother which is explained as below:

Production schedule:

The main aim is to schedule that amount of work whichcan easily be handled by plant and equipment without interference. It’s notindependent decision as it takes into account following factors.

(1) Physical plant facilities of the type required to process the material beingscheduled.

(2) Personnel who possess the desired skills and experience to operate theequipment and perform the type of work involved.

(3) Necessary materials and purchased parts

Master Schedule:

Scheduling usually starts with preparation of master schedulewhich is weekly or monthly break-down of the production requirement for each product for a definite time period, by having this as a running record of total production requirements the entrepreneur is in better position to shift the production from one product to another as per the changed productionrequirements. This forms a base for all subsequent scheduling acclivities. Amaster schedule is followed by operator schedule which fixes total time requiredto do a piece of work with a given machine or which shows the time required todo each detailed operation of a given job with a given machine or process.

Manufacturing schedule:

It is prepared on the basis of type of manufacturing process involved. It is very useful where single or few products are manufactured repeatedly at regular intervals. Thus it would show the required quality of each product and sequence in which the same to be operated

Scheduling of Job order manufacturing:

Scheduling acquires greater importance in job order manufacturing. This will enable the speedy execution of job at each center point. As far as small scale industry is concerned scheduling is of utmost importance asit brings out efficiency in the operations and reduces cost price. The small entrepreneur should maintain four types of schedules to have a close scrutiny of all stages namely an enquiry schedule, a production schedule, a shop schedule andan arrears schedule out of above four, a shop schedule is the most important most suited to the needs of small scale industry as it enables a foreman to see at aglance.

Loading:

The next step is the execution of the schedule plan as per the routechalked out it includes the assignment of the work to the operators at their machines or work places. So loading determines who will do the work as routingdetermines where and scheduling determines when it shall be done. Gantt Chartsare most commonly used in small industries in order to determine the existingload and also to foresee how fast a job can be done. The usefulness of their technique lies in the fact that they compare what has been done and what ought tohave been done.

Production control:

Production control is the process of planning production inadvance of operations, establishing the extract route of each individual item partor assembly, setting, starting and finishing for each important item, assembly or the finishing production and releasing the necessary orders as well as initiating thenecessary follow-up to have the smooth function of the enterprise

Dispatching:

Dispatching involves issue of production orders for starting theoperations. Necessary authority and conformation is given for:

• Movement of materials to different workstations.
• Movement of tools and fixtures necessary for each operation.
• Beginning of work on each operation.
• Recording of time and cost involved in each operation
• Movement of work from one operation to another in accordance with theroute sheet.
• Inspecting or supervision of work Dispatching is an important step as it translates production plans into production

Follow up:

• Every production programme involves determination of the progressof work, removing bottlenecks in the flow of work and ensuring that the productive operations are taking place in accordance with the plans.
• It spotsdelays or deviations from the production plans.
• It helps to reveal detects in routingand scheduling, misunderstanding of orders and instruction, under loading or overloading of work etc.
• All problems or deviations are investigated and remedialmeasures are undertaken to ensure the completion of work by the planned date.

Inspection:

This is mainly to ensure the quality of goods. It can be required aseffective agency of production control.

Corrective measures:

• Corrective action may involve any of those activities of adjusting the route, rescheduling of work changing the workloads, repairs andmaintenance of machinery or equipment, control over inventories of the cause of deviation is the poor performance of the employees.
• Certain personnel decisionslike training, transfer, demotion etc. may have to be taken.
• Alternate methods may be suggested to handle peak loads