11 Indicators of Device Management

In enterprises, there are many indicators used to measure the quality of equipment management. For example, equipment integrity rate, equipment availability rate, equipment comprehensive efficiency, equipment fully effective productivity, equipment failure rate, mean time between failures, mean repair time, equipment spare parts inventory turnover rate, spare parts funding rate, maintenance cost rate, and maintenance quality once Qualification rate, repair rate, etc. Different indicators are used to measure different management directions.

➤ Indicator evaluation of equipment management

1. Equipment integrity rate

It is the most commonly used among these indicators, but its promotion effect on management is limited.

The so-called integrity rate refers to the ratio of intact equipment to the total number of equipment during the inspection period (equipment integrity rate = number of intact equipment/total number of equipment). The indicators of many factories can reach more than 95%. The reason is simple. At the moment of inspection, if the equipment is running and has no faults, it is considered intact, so this indicator looks good. If it looks good, it means there is not much room for improvement, it means there is nothing to improve, which means it is difficult to make progress. For this reason, many companies have proposed to reform the definition of this indicator. For example, they proposed to inspect three times on the 8th, 18th, and 28th of each month, and take the average of the integrity rates as the integrity rate for this month. This is certainly better than a single inspection, but is still a dotted representation of the integrity rate. Later, someone proposed that the number of intact bench hours should be compared with the calendar workbench hours. The intact bench hours equal the calendar workbench hours minus the total bench hours for breakdowns and repairs. This indicator is much more realistic. Of course, we are faced with the increase in the workload of statistics and the authenticity of statistics, and the debate on whether to deduct the preventive maintenance station. Whether the indicator of integrity rate can effectively reflect the status of equipment management depends on how it is applied. Different people have different opinions and wisdom.

2. Equipment failure rate

This indicator is easily confused and has two definitions:

1. If it is a fault frequency, it is the ratio of the number of faults to the actual number of times the equipment is started (failure frequency = number of fault shutdowns/actual number of times the equipment is started);

2. If it is a failure shutdown rate, it is the ratio of the time when the machine is down due to failure to the time when the equipment is actually started plus the time when the machine is down due to failure (failure shutdown rate = the time when the machine is down due to failure/(the time when the equipment is actually started up + the time when the machine is down due to failure) )

Obviously, the downtime rate can truly reflect the status of the equipment.

3. Equipment availability

It is mostly used in Western countries, but in our country there are two differences: planned time utilization (planned time utilization = actual working time/planned working time) and calendar time utilization (calendar time utilization = actual working time/calendar time) formulation. By definition, Western-defined availability is actually calendar time utilization. Calendar time utilization reflects the full utilization of the equipment, which means that even for equipment running in a single shift, we calculate calendar time based on 24 hours. Because regardless of whether the factory uses this equipment, it consumes the company's assets in the form of depreciation. The planned time utilization reflects the planned utilization of the equipment. If it is operated in a single shift, the planned time is 8 hours.

4. Equipment mean time between failures

Another formulation of MTBF is called mean working time between failures (mean time between equipment failures = total failure-free operation time in the statistical base period/number of failures). It complements the downtime rate and reflects the frequency of failures, that is, the health of the equipment. It is enough to choose one of the two indicators, and there is no need to use related indicators to measure a content.

Another indicator that reflects maintenance efficiency is the average repair time MTTR (average repair time = total time consumed in statistical base period maintenance/number of repairs), which measures the improvement of maintenance work efficiency.

With the advancement of equipment technology, its complexity, maintenance difficulty, fault location, average technical quality of maintenance technicians and equipment service age are different. It is difficult to have a definite value for maintenance time, but we can measure its average condition and progress based on this. .

5. Equipment comprehensive efficiency

OEE is an indicator that comprehensively reflects equipment efficiency. OEE is the product of time operation rate, performance operation rate and qualified product rate. Just like a person, the time utilization rate represents the attendance rate, the performance utilization rate represents whether he works hard after work and exerts his due efficiency, and the qualified product rate represents the effectiveness of the work, whether mistakes are often made, and whether the task can be completed with quality and quantity. .

The simple OEE formula is: overall equipment efficiency OEE = qualified product output/theoretical output of planned working time (see above for detailed explanation)

6. Completely effective productivity

TEEP is the formula that most thoroughly reflects equipment efficiency rather than OEE. Fully effective productivity TEEP = qualified product output/theoretical output in calendar time. This indicator reflects the system management defects of the equipment, including upstream and downstream effects, market and order effects, equipment capacity imbalance, unreasonable planning and scheduling, etc. come out. This indicator is generally very low, not good-looking, but very real.

➤ Regarding maintenance and management, there are also relevant indicators reflected

1. First pass rate of maintenance quality

It is measured by the number of times the equipment has been tested to meet product qualification standards after maintenance compared to the number of maintenance times. Whether the factory uses this indicator as a performance indicator for the maintenance team can be studied and scrutinized.

2. Repair rate

It is the total number of repairs after the equipment is overhauled compared to the total number of overhauls. This more truly reflects the quality of maintenance.

3. Maintenance cost rate

There are many definitions and algorithms. One is the ratio of annual maintenance costs to the total annual output value. Another is the ratio of annual maintenance costs to the total original value of assets in the year. Another is the ratio of annual maintenance costs to the total replacement cost of assets in the year. Another one is the ratio of the annual maintenance fee to the total net asset value of the year, and the last one is the ratio of the annual maintenance fee to the total production cost of the year.

So I think the last algorithm is more reliable. Even so, the size of the maintenance cost rate does not explain the problem. Because equipment maintenance is an input, and input creates value and output. Insufficient investment and prominent production losses will affect output; of course, too much investment is not ideal and is called excess maintenance, which is a waste. Proper investment is ideal.

Therefore, factories should explore and study the best investment ratio. High production costs mean more orders and tasks, and the load on equipment increases, which also increases the demand for maintenance. Investing in the right proportion is what the factory should strive to pursue. If you have this benchmark, the further you deviate from this indicator, the less ideal it is.

➤There are also many indicators regarding spare parts management

1. Spare parts inventory turnover rate

(Spare parts inventory turnover rate = monthly spare parts consumption costs/monthly average spare parts inventory funds) is a more representative indicator. It reflects the liquidity of spare parts.

If there is a large backlog of inventory funds, it will be reflected in the turnover rate. Spare parts management also reflects the spare parts funding rate, which is the ratio of all spare parts funding to the total original value of the enterprise's equipment. The value of this value varies depending on whether the factory is in a central city, whether the equipment is imported, and the impact of equipment shutdown losses.

If the equipment downtime costs tens of millions of yuan per day, or the failure causes serious environmental pollution or serious personal safety hazards, and the spare parts supply cycle is long, the spare parts inventory will be higher. On the contrary, the spare parts funding rate will be as high as possible. reduce

2. Maintenance training time intensity

(Maintenance training time intensity = maintenance training hours/maintenance working hours) The training includes equipment structure professional knowledge, maintenance technology, professional quality and maintenance management. This indicator reflects the importance and investment intensity of the company in improving the quality of maintenance personnel, and also indirectly reflects the level of maintenance technical capabilities.