Managing maintenance need not be costly or difficult. Just ask the approximately 30% of plant sites in North America that have no formal CMMS. These plants have established manual procedures that help maintenance professionals decrease equipment downtime and improve asset availability and performance. This approach is particularly applicable to facilities with five or fewer maintenance technicians, but it depends on the size of the facility, shift coverage, whether it has a centralized or decentralized organizational structure, number and complexity of assets, and other factors.
All that’s needed for a manual system is paying attention to careful recordkeeping. Success with any maintenance control project depends on using the right methods to plan, distribute and monitor work. Simple means exist for controlling your maintenance operation, including setting up a manual work order control system, preventive maintenance program, inventory control system and equipment history file.
Work order control
Work order control is the focus of a maintenance management system. The work order and time card are two essential documents that provide input and information for a simple manual system. For each job, the person responsible for maintenance planning receives or completes a work order form. Based on the pile of backlogged work orders, the designated planner, supervisor or lead technician can assign work daily for each mechanic. A copy of every issued work order is placed into an active work order file. Each technician completes the necessary work as described on the work order, then prepares the feedback information, including a time card. The completed work orders and time sheets go back to the planner after a job is finished. The work order, standing work order, daily time card and scheduling board each has its own important function.
The work order authorizes the maintenance staff to perform work, provides a brief description of the work required, identifies the priority of the work and its required completion date, and provides a work history record when completed. The planner relies on personal experience and any available historical data to help estimate the labor hours required to complete a job. The estimate can then be used to evaluate planned-versus-actual hours to complete the work.
Standing work orders (SWO) use standard code numbers for routine or repetitive jobs that usually take less than 30 minutes to complete. Using SWOs helps the planner avoid issuing a regular work order for such jobs, thus reducing the technician’s clerical load associated with completing lengthy forms. Where applicable, each SWO has an established time standard. This includes setups, changeovers, daily inspections and cleanup. The standards enable the planner to monitor the hours charged per SWO per employee. The code numbers used for charging labor hours can be preprinted on the back of the time card or posted for easy reference.
The purpose of the daily time card is to allocate an employee’s labor hours to the appropriate (standing) work order number or cost center. The time card each maintenance technician completes can be used by the finance department for payroll purposes. Materials used also can be tracked. The planner monitors the total labor hours for each work order, and examines the description of work done to evaluate the success of the different jobs and monitor technician performance.
The typical scheduling board lists every technician and has three slots to hold current work orders, future work orders and temporarily abandoned work orders for the day. Thus, the planner can keep track of the whereabouts of the crew and the status of current, future or interrupted jobs. It’s also easy for each technician to pick up the next job assignment from the board to maximize labor utilization.
Preventive maintenance
The purpose of preventive maintenance is to establish routines that make the cost of equipment breakdown no more than the cost of the PM program. Breakdown costs to consider, other than the cost of repair, are equipment damage, lost or poor quality production, equipment replacement and safety.
Identify PM routines for every asset. These preprinted routines or checklists should be completed by each technician upon completion of the PM work. Sometimes resident department mechanics perform the PM work for their respective areas, or one or more technicians are dedicated to PM. Two major components of a manual PM system are the tickler file and the hours-of-use chart.
A manual or computerized tickler file can organize calendar-based work so that it can be brought to the planner’s attention at the appropriate time. The planner will have a file folder for each day of the month and a file folder for each of the next 12 months. A “future years” folder is used for periods farther ahead than this.
An hours-of-use chart, manual or spreadsheet-based, identifies when PM work is to be performed on vehicles or other assets that require maintenance on the basis of accumulated hours of use. Hours of use are collected manually or through monitoring devices such as meters. A similar chart can be used for other measures of use such as gallons of water consumed, kilowatts of power dissipated, etc.
Inventory control
The objective of an inventory control system is to provide the maintenance staff with an adequate supply of spare parts inventory while minimizing the cost of carrying the hardware. Inventory should be easily accessible and controllable, using a simple system.
The two-bin system is the simplest inventory control system. Parts are stored in two containers or bins. One is open and the other sealed; maintainers draw from the open bin.
The seal is broken only when the open bin is depleted. Breaking the seal initiates an order for another container of parts. A variation on the theme uses a single bin, but segregates a number of parts (safety stock) in a box or bag within the bin. When the sealed bin or segregated parts are accessed, the technician picks up a reorder card at the bottom of the depleted bin and delivers it to the supervisor or directly to the purchasing agent for reordering of the parts.
The buyer places the order and annotates the card with the date and the quantity ordered. The card is then returned to the depleted bin. The technicians continue drawing from the safety stock until the order is received and the bin is replenished.
Equipment history
Filing manual work orders and PM checklists chronologically by assets produces a complete history of work done for each asset. A simple spreadsheet can provide more accurate tracking of time and materials charged to a given work order and, in turn, to a given asset.
A regular scan through the spreadsheet or work orders filed for a given asset can reveal major problem areas. The spreadsheet also can help calculate the breakdown of total hours booked as emergency, regular unplanned, preventive, planned and standing work orders. This allows the planner to adjust the schedule, staffing or processes to eliminate problem areas such as excessive emergency work or abuse of SWOs.
E-mail Contributing Editor David Berger, P.Eng., at [email protected]
