**1.6 Equipment records**

Equipment records consist the files including inventory, job performed, and maintenance cost. All these activities are well mannered which can be done while performing the jobs. Also, the maintenance costs are categorized in a historic profile manner. In general, stores and accounting departments provide the information regarding inventory. Operations, drawings, service manuals, warranties and so on are included in the files.

#### **1.7 Maintenance job planning**

possibilities of running out of stock caused from the dwell lead time and the random variability of demand. The outcome of the stock holding is as shown in **Figure 1**. Here, solid lines describe the stock held, and the dotted lines reveal about stock

*<sup>q</sup>* <sup>¼</sup> ffiffiffiffiffiffiffiffiffiffiffiffi

where q = reorder quantity; Co **=** ordering cost; D = mean demand per unit time;

*<sup>M</sup>* <sup>¼</sup> *DL* <sup>þ</sup> *<sup>K</sup><sup>σ</sup>* ffiffiffi

where L **=** lead time, *σ* ¼standard deviation of demand per unit time, k **=** normal

A work order is approved and given the directions in a separate or group vise to carry out the tasks. In this, all maintenance activities and responsibilities are covered to control the costs and to enhance the job performance. Work order should at least contain information such as requested and planned completion dates, work description and its reasons, planned start date, labor and material costs, item or items to be affected, work category, and appropriate approval signatures.

1.The documents required to facilitate work planning, execution and control,

2.The basic documents required for the work order system include the work order, materials and tools requisition forms, job card, maintenance schedule,

maintenance program, plant inventory, and equipment history files.

*L*

<sup>2</sup>*D*Co <sup>p</sup> *<sup>=</sup>*Ch (1)

<sup>p</sup> (2)

on-hand.

**Figure 1.**

Ch **=** holding cost.

standard variety.

**310**

The expression for re-order quantity is:

*Operations Management - Emerging Trend in the Digital Era*

*Re-order level (source MTB by Alembazezwu).*

Assume stack is re-ordered at regular time interval. Lead time between order and delivery is negligible.

Negative stack is not allowed by the policy.

Constant rate of demand per unit. The reordering level M is calculated as:

**Maintenance work order system**:

The two main parts of work order system are:

and the work order flow process.

Job planning is an essential element of the effective maintenance management. A number of tasks may have to be performed prior to commencement of a maintenance job; for example, procurement of parts, tools, and materials, coordination and delivery of parts, tools, and materials, identification of methods and sequencing, and coordination with other departments. Job planning is considered as a main technique to make good observations and preventive maintenance. Here, the primary job is to complete what parts to be maintained and what is the best method to enhance the performance of the jobs. Skills, talent, and good deal time are necessary to accomplish the better procedures. However, this should be performed to gain the good experience to train the future design engineers. But, writing skills are also an important qualification along with practical experience in many practices. The way of writing the language is short, concise, and clear to understand easily. All the statements should be written clearly and the following should be followed strictly:


When the procedure is completed and turned into maintenance control, the planner or scheduler should note any additional work required and see that it gets done according to priority.

#### **1.8 Maintenance scheduling**

Maintenance scheduling is as important as job planning. Schedule effectiveness is based on the reliability of the planning function. Fixed interval maintenance tasks and schedules are generally to be considered only when the option has to control the failures detected in advance. Hence, the planning for identifications and preventive levels can be finalized in days, weeks, and even months together soon to make sure that the time for production must be convenient.
