Many foundries are operating at increased capacity due to the strong economy and many still are projecting increased sales through the next few years.
The good economic expansion is greatly welcomed in our industry and we see strong enthusiasm for new equipment and foundry expansion. Sales growth, production commitments, never ending quality improvements are all outcomes of increased demand. These customer and operational demands are ever harder to achieve when your foundry equipment experiences unplanned downtime.
Over the last several months we’ve spent a lot of time working with many foundries across North America to help with service and ex-pediting replacement parts. We all know how it works; when busi-ness is down certain expenses are pulled back. Routine maintenance is limited. Wear items needing replacement are Band-Aid-ed until complete failure. Spare parts inventory is depleted and not replaced. It seems our industry was hit overnight with ramped-up capacity and production. This almost immediate increase in production caught many with neglected equipment and really not ready to take the machinery to near 100% capacity. Furthermore, we know many of our foundry customers freely admit to neglecting their machinery because there just isn’t any downtime in the schedule to preform basic preventive maintenance activities.
Today’s foundries are operating a wide age of equipment; from 50’s era squeezers to highly complex multi-piston compensating high pressure molding systems. Each end of the spectrum requires the same attention to detail, consideration of spares inventory, and establishing an effective maintenance program. This article is intended to help reinforce how important a preventative maintenance program is to your foundry and your profitability. The article will offer some basic preventative maintenance considerations and work outline some steps to get started or re-engage your operations team.
STEPS IN A PREVENTIVE MAINTENANCE PROGRAM
The first step is ownership or management adoption of reinforcement of a preventative maintenance program. It often happens that programs are installed with great initial enthusiasm but collapse completely after a relatively short period. Many times, this can be traced to inadequate ongoing support from management. It is critical that management instill a demanding preventative maintenance culture.
Other common reasons for a weak preventative maintenance program are; failure to plan accordingly, inadequate initial training of the preventive maintenance staff, insufficient time for the transition from the “break-down repair squad” philosophy to true preventive maintenance thinking, disillusionment since positive results are not immediately evident.
Assemble your team, establish goals and metrics, create a funding resource, and meet routinely to review and discuss results. Only after routine conversation will you be able to reinforce the importance of a robust preventative maintenance program.
After committing to the plan, your next step should be to compile a list of production machines and equipment directly involved in the manufacturing process. That equipment list should be grouped according to their importance to the production process.
I. Indispensable Machines
are defined as those whose breakdown would interrupt one or more steps in the entire production process and for which no standby unit exists, or whose function cannot be performed temporarily by alternative means. The single cupola of a small foundry is an example.
II. Marginal equipment
contributes indirectly to the production process but its breakdown would not be a major inconvenience. The foundry clean-up truck is an example.
This method of classifying machines is similar to the process used in network analysis to determine (critical) and (non-critical) activities.
After every piece of equipment has been given a maintenance priority rating, it is possible to establish an appropriate preventive maintenance program which will maintain each item in the condition appropriate to its rating. The frequency and care with which each machine is serviced are determined by factors specific to that machine in its particular environment.
It is therefore not feasible to describe valid preventive maintenance procedures to cover all possible situations; however, certain guidelines can be set forth which will help to determine those components of machines and equipment, which should receive primary attention.
The equipment components, which should be located and clearly identified when setting up a preventive maintenance program include:
A. All lubrication points
B. All electric motors or driving mechanisms
C. All electrical control equipment
D. All hydraulic and pneumatic components
E. All mechanical parts of assem-blies subject to appreciable wear
This survey should not be based solely on manufacturer’s drawings. Identify each element by actually inspecting the equipment concerned and then mark these in on suitable plant layout drawings.
After the above steps are completed, then define the plant areas that need to receive some form of preventive maintenance – so that specific preventive maintenance work schedules can be established.
SETTING UP A LUBRICATION PROGRAM
The lubrication program can be developed in a straightforward manner by following the simple steps described below:
I. Standardize and code lubricants – From equipment manufacturer’s service manuals and data from lubricant suppliers establish a minimum number of standard lubricants which will cover all equipment needs.
II. Set up a central storage area for all lubricants – Ensure that lubricants are stored in such a manner that sand or other impurities cannot contaminate them. Such care will pay handsome dividends in prolonged machine life.
III. Determine the frequency of lubrication – Machine priority ratings, lubricant supplier’s data and past plant records are used to determine both the frequency with which each lubricating point should be serviced and the type of standard lubricant to be used.
IV. Compile a lubricating schedule – Use the established lubrication criteria above to determine the lubricating workload on each machine.
Next, compile a series of master checklists in the form of lubricating schedules.
EQUIPMENT INSPECTION PROGRAM
An equipment inspection program can be developed in a manner similar to the lubrication program just described. Use machine priority ratings and past plant experience to establish:
A. Items of equipment requiring regular inspection
B. Type of inspection necessary (visual, audible, measured) *
C. Frequency of each type of inspection
D. Corrective maintenance procedures to be used to prevent the recurrence of unexpected equipment breakdowns
* Rounds and readings are fairly common start of shift activities. Its also advisable to provide some basic training to the oper-ators. Simple sensory observations of sound, smell and touch can help to avoid a catastrophic outage.
Once the inspection methodology has been established the maintenance department must procure the inspection tools. Transfer the relevant inspection data to a set of machine inspection cards, log sheets, or appropriate software.
Record daily the work completed, using a standard check sheet. Require a signature at the end of each shift as evidence of having completed the work. Assigning responsibility to individuals in this way motivates them to complete their duties conscientiously and makes it possible to pinpoint responsibility for machine breakdowns.
Where a need for maintenance work outside the scope of adjustments is required a standard maintenance request form needs to be submitted to the maintenance department.
MACHINE RECORDING SYSTEMS
In order to keep vital equipment running and minimize production delays resulting from break-downs, it is important to have on hand a selection of the important spare parts needed for individual machines. It is also important to have some record of the frequency with which such spare parts are used so that inventories can be held to economic levels.
To achieve this, it is necessary to set up a file of equipment repair history records. These should contain the important technical data of each machine, and in addition should list those parts of each machine, which are to be kept in inventory for repair purposes. Each data entry should also record the date, nature, duration, and cost of every repair made to each piece of equipment listed. This information is important in reaching decisions concerning replacement of equipment.
Modern preventative maintenance software applications offer numerous templates that can tabulate all this data into one place.
Implementation of a program such as outlined above, may require some modification to the structure of the existing maintenance organization to accommodate the changes in procedures, which will result. Preventive maintenance supervisors must be appointed, clerks must be trained, and preventive maintenance foremen selected. This organization can be built up gradually since the information gathering phase of the program, which is fundamental to its success, is necessarily somewhat time consuming.
The success of a preventive maintenance program is largely dependent on the ability of the preventive maintenance supervisors to implement completely the inspection, lubrication and corrective maintenance procedures. This means that the program must have the complete support of top management and that the supervisors, themselves must be able to exercise a proper degree of authority over those areas for which they are held responsible.
As the improved inspection methods help to determine with greater accuracy when individual pieces of equipment should be overhauled, breakdowns will become less frequent. The maintenance workshop will now be called upon to undertake preplanned overhauls when machines become available during off-production time.
The function of the shops will thus gradually move away from the emergency squad activities toward controlled machine servicing activities. The understanding and enthusiasm of those responsible for the execution of a preventive maintenance program are important factors in determining its ultimate success.
Consequently, it is important that both supervisory and technical personnel in the group receive formal training in the reasons for, philosophy behind and benefits derived from a preventive maintenance program.
The success of the program also depends on obtaining the full support and understanding of production personnel. They must cooperate by advising of running difficulties experienced with machines, modifications made to equipment and areas where the existing program is in need of revision. Moreover, they must understand that inspection is the key to successful preventive maintenance and be prepared to put each machine at the disposal of the preventive maintenance group at agreed times so that the necessary inspection and over-hauls can be performed.
PREVENTIVE MAINTENANCE PROGRAM BENEFITS
A sound preventive maintenance program provides important benefits:
I. Reduced Downtime – An initial result of such a program is a sharp drop in the number of equipment breakdowns. This expresses itself directly as an increase in production machine running time and therefore in greater total work output.
II. Reduced Equipment Repair Costs – When machines are inspected regularly, the likelihood of detecting abnormal functioning, which may lead later to a serious breakdown of complicated repair, is greatly increased. The early detection and correction of minor operating irregularities in equipment leads to reduced overall expenditure on repairs.
III. Reduced Maintenance Work Force – As the need to carry out major repairs diminishes, manpower requirements for such work also diminish and it should eventually be possible to reduce the size of the maintenance force.
IV. Longer Equipment Life –Machines that are lubricated and inspected regularly will naturally remain in proper working order for a longer period.
If your foundry embraces the importance of a robust and well-run preventative maintenance organization your ahead of many of your peers. If your foundry abandoned preven-tative maintenance in favor of production commitments, we hope you’ll take this article as a friendly reminder about the importance a preventative main-tenance program plays in your long-term success. If you need help re-establishing an effective program, we can help with any portion of these suggested step.