Preventive maintenance (PM) is a schedule of planned maintenance actions aimed at the prevention of breakdowns and failures. The primary goal of preventive maintenance is to prevent the failure of equipment before it actually occurs. It is designed to preserve and enhance measurement instrument reliability and accuracy by replacing wearable or worn components before they fail. Preventive maintenance activities include both mechanical component and electronic circuitry checks and adjustments, partial or complete component or circuitry replacements at specified periods, cleaning, lubrication and so on. If done periodically, equipment wear and deterioration can be recorded and closely followed so that maintenance actions can be planned well ahead to minimize or eliminate equipment down time.

One should not compare only the costs but also the long-term benefits and savings associated with preventive maintenance when planning instrument maintenance. Without preventive maintenance, for example, costs for lost productive time from unscheduled equipment breakdown will be incurred. Also, failure of a component or a sub-system caused by lack of maintenance may cause subsequent failures of the instrument further increasing repair costs. Finally, preventive maintenance will also result in savings due to an increase of effective system service life.

Long-term benefits of preventive maintenance include:

Improved reliability

Decreased measurement instrument downtime

Longer measurement instrument lifecycle

Decreased cost at the time of rebuild

What is Corrective Maintenance?

Corrective maintenance (CM) is a maintenance action to resolve breakdowns and failures. As such the corrective maintenance usually consists of down time, depending of the severity of the instrument failure. The failure rate of a component typically increases with time. Therefore, the older the measurement instrument is the more costly the corrective maintenance will be if preventive maintenance has been ignored.

Calibrations

What is calibration?

Calibration is the comparison of an instrument's measurement performance to a certified standard of known accuracy. The result of a calibration consists of adjusting the instrument's measurement capability to improve measurement accuracy, and documentation showing the deviation of a measurement from the known standard. The goal of calibration is to quantify and improve the measurement accuracy of your instrument to meet or exceed factory specifications.

The most basic requirement of a calibration is proof of traceability. Traceability is the unbroken chain of comparisons between your measurement instrument and national or international standards. This means that your equipment accuracy is traceable to known standards of certain accuracy.

Why calibrate?

The accuracy of the electronic components used in all instruments drifts over time. The ability of a measurement device to accurately measure something changes with a number of factors. Time in service, temperature, humidity, environmental exposure, and abuse all affect the measurement accuracy. As time progresses, changes in component values cause greater uncertainty, and measurement error, in your measurements. At some point the drift causes the instrument's uncertainty to become undefined, meaning the measurement results can no longer be guaranteed. To resolve this issue instruments must be calibrated at regular intervals, which ensures that the component drift and thus the measurement uncertainty are always controlled and compensated for.

The goal of calibration is to quantify, improve and maintain the measurement accuracy of your instrument. The benefits of maintaining properly calibrated equipment include:

Assurance of accurate measurements

Reduced measurement errors

Consistency between measurements

Increases in production yields

Ability to trace your measurements back to a know standard

Ability to meet requirements of quality programs such as ISO-9001

How to calibrate?

When your measurement instrument time in service reaches its specified calibration interval, you should contact HP Engineering for calibration service. We will measure and compare your instrument’s measurements to external certified standards, and make adjustments to your instrument measurement circuitry to improve its accuracy. The basic calibration includes:

Evaluation of the instrument’s capabilities to determine “as found” accuracy

Adjustments of measurement circuitry and signal references against known references

Verification of the measurement to determine “as left” accuracy

Issuance of calibration certificate, stating that the instrument measures within specifications against to a traceable standard

What about self-calibration?

Some instruments use internal circuitry and signal references instead of known external references to adjust its measurement accuracy. This is called self-calibration. This calibration method is often times fully automated requiring minimal inputs from the operator. However, self-calibration does not take into account for the drift in internal circuitry and signal references, causing uncertainty and thus measurement errors over time. Therefore self-calibration does not replace calibration that is done with external, certified standard of known accuracy. One must quantify the internal circuitry and signal references used in self-calibration with external references in order to ensure the measurement accuracy of the instrument.

Service and Calibration Agreements

We offer on-site preventive maintenance, calibration and operator training on service agreement basis that typically includes two visits per year. We also offer corporate service agreements that cover equipment service and calibration on multiple locations.

Installations and operator refreshment training

Installations

If measurement instrument has not been used for a long time or it has been moved to a new location it needs to be checked and re-installed. HP Engineering provides complete checkout of equipment prior to equipment startup or existing system restart. We have the experience to fully teach and train each operator to make sure the equipment is used to its fullest extent. We also provide start-up checklist and hourly training schedule prior installation day so that daily duties can be accommodated within the given time frame.

Operator Refreshment Training

HP Engineering provides basic measurement task refreshment training, and advanced refreshment training for operators who want to expand their knowledge level in order to utilize their measurement equipment more efficiently

Quality systems (SPC/SQC) implementation consulting

HP Engineering provides basic SPC training for those clients who want to get familiarized themselves with common statistical tools and methods used in conjunction with their measurement equipment. We also provide consulting to those clients who want to implement and utilize their own SPC/SQC systems with their measurement equipment.

Components outsourcing and consulting

HP Engineering can help you keep your measurement instrument running even if the required parts are no longer readily available. We can outsource, install and repair obsolete parts on component level, or remanufacture any part assemblies you might need.

 Instrument sub-system upgrades on component level

Sometimes it is better to replace obsolete part or assembly with an updated version of the same or similar component or assembly. HP Engineering provides upgrade engineering and installation services in order to keep your equipment running regardless of its age.

Upgrade and modification services

HP Engineering provides various upgrades and modifications from simple PC updates to complete equipment rebuilds. Please contact us in order to find out what updates are available for your equipment.

Phone, email and fax support

We provide phone, email and fax support to our clients with questions about instrument usage or to help them with troubleshooting when necessary.