Preventive maintenance is often summarised as: maintaining before an installation fails. That principle is logical, but in practice, it is not enough. Not every component is equally critical, not every defect has the same consequences, and not every installation requires the same maintenance interval.

An effective maintenance strategy therefore does not start with the calendar, but with insight. Which components are essential for the safety, availability, and continuity of the process? Which failure mechanisms can occur? And which form of maintenance suits the risk and the technical condition of the installation?

By organising maintenance on a risk-based footing, work can be planned more effectively and deviations become visible sooner. The result is greater control over installation condition, maintenance priorities, and business continuity.

Not every component requires the same maintenance approach

A fixed maintenance interval may be practical, but it does not automatically take into account the actual condition and criticality of a component.

A hydraulic installation, for example, can consist of:

• hydraulic pumps;
• cylinders;
• hydraulic hoses;
• seals;
• filters;
• valves;
• piping;
• power packs;
• sensors;
• electrical and electro-hydraulic controls.

A defect in a redundant or easily replaceable part may have limited consequences. Conversely, failure of a safety-critical actuator, pump, or valve can affect the availability of an entire installation.

That is why it is wise to determine the following for each installation or system part:

1. What function does the component perform?
2. What happens when the component fails?
3. What are the consequences for safety, production and the environment?
4. How likely is it that the failure mechanism will occur?
5. Is deterioration measurable in advance or identifiable during an inspection?
6. Which type of maintenance manages the risk most effectively?

Based on this, a distinction can be made between periodic, condition-based and corrective maintenance.

Periodic, condition-based or corrective maintenance?

Preventive maintenance does not mean that every component must be replaced as standard after a fixed period. The right approach depends on the function, condition and consequences of failure.

What is periodic maintenance

With periodic maintenance, tasks are carried out according to a predetermined schedule. This can be suitable for components where it is known that wear is related to service life, load, operating hours or a prescribed inspection cycle.

Examples include:

• checking or replacing filters;
• inspecting hoses and connections;
• checking settings and safety devices;
• lubricating moving components;
• functionally testing systems.

What is condition-based maintenance

With condition-based maintenance, measurements and inspection results determine when intervention is necessary. Think of oil sampling, pressure measurements, performance measurements and visual inspections.

Integron carries out preventive oil sampling, among other things, and uses the results to determine whether filtering or an oil change is appropriate. In addition, hydraulic pumps can be tested on a computer-controlled test bench, after which a test report provides insight into performance and potential follow-up actions.

What is corrective maintenance?

Corrective maintenance is carried out after a defect or failure has been identified. For some non-critical and easily replaceable parts, this can be a deliberate choice. For components with significant safety or continuity implications, relying solely on reactive maintenance is usually less desirable.

Therefore, a maintenance strategy does not have to be entirely preventive or entirely corrective. A sound approach combines different forms of maintenance based on risk, technical condition, and business importance.

Why does not every installation require the same maintenance approach?

Before a maintenance plan is drawn up, it must be clear which parts are crucial to the process. A criticality assessment helps to rank installations and components based on the consequences of failure.

This can include looking at:

• personal and process safety
• environmental and surrounding area impact;
• product loss;
• installation availability;
• influence on other systems;
• repair time;
• availability of spare parts;
• accessibility of the component;
• possibility of temporary operation;
• legal, regulatory, and contractual obligations.

A criticality assessment prevents all components from receiving the same level of attention. This allows people, time, and budget to be deployed where a failure would have the greatest impact.

How failure history and condition data help to plan maintenance more intelligently

A maintenance plan is more robust when it is based on technical data rather than just fixed intervals.

Relevant information can include:

• previous breakdowns;
• recurring leaks;
• oil analyses;
• pressure and temperature measurements;
• abnormal noises or vibrations;
• test results for pumps, cylinders and hoses;
• wear patterns;
• replacement history;
• technician reports;
• changes in load or usage.

By systematically assessing this information, patterns become visible. When a component repeatedly shows the same fault, simple repair may not be enough. In such cases, it is necessary to investigate whether the root cause lies in the sizing, contamination, adjustment, load, installation or control.

In addition to maintenance, Integron also provides engineering, new construction, overhaul and modernisation of hydraulic systems. In certain situations, existing power packs can be redesigned or overhauled, meaning complete replacement is not always necessary.

Why contaminated hydraulic oil is one of the biggest risks for breakdowns

The condition of hydraulic oil has a direct impact on how a system operates. Contamination can accelerate wear, affect valves and reduce the performance of pumps and other components.

Causes can include:

• dirt ingress during installation or maintenance;
• inadequate filtration;
• wear particles from the system;
• degraded oil;
• water or condensation;
• careless refilling;
• insufficient cleaning after a repair.

Oil sampling can help to identify contamination and changes in oil condition. The results must then be translated into an appropriate measure, such as additional filtering, further technical investigation, or oil replacement. The action required depends on the system, the application, and the investigation results.

How safe maintenance starts with proper preparation

Maintenance on hydraulic and industrial installations can involve risks. Consider stored energy, high pressure, moving parts, heavy components, potential leaks, and unexpected movements during testing.

That is why safe maintenance begins before any tools are used. Work must be prepared within the procedures and responsibilities of the relevant client and site.

Key points include:

• correctly identifying the installation and system boundaries;
• assessing foreseeable risks in advance;
• securing the installation;
• managing pressure and stored energy;
• coordinating work permits and responsibilities;
• determining appropriate measures and personal protective equipment;
• carefully documenting changes and work performed;
• testing and releasing the installation in a controlled manner afterwards.

When working on gas, energy, and process installations, the specific regulations of the asset owner are always leading. A general maintenance article cannot replace these site- and installation-specific procedures.

What should you look for during an inspection of a hydraulic installation?

An inspection is only valuable when it is clear what is being checked, how results are assessed, and what follow-up is required.

An inspection of a hydraulic installation can, for example, focus on:

• visible leakage;
• damage to hoses and pipework;
• wear of couplings;
• corrosion;
• contamination;
• oil condition;
• pressure and temperature levels;
• operation of pumps and valves;
• performance of cylinders and actuators;
• fixing and support of pipework;
• operation of safety devices and controls.

Not every deviation requires immediate replacement. The severity must be assessed in relation to the risk of failure, the function of the component, and the operational conditions.

We view preventive maintenance as a combination of maintenance and inspection. Afterwards, you will receive a maintenance report from us detailing points of interest and, where necessary, a proposal for repairs.

Why testing after maintenance is essential for a reliable installation

A completed repair does not automatically mean that an installation can be safely put back into operation. After maintenance, it must be verified that the system is functioning as intended.

Depending on the installation and the work carried out, verification may consist of:

• visual inspection;
• leak test;
• pressure test;
• functional test;
• setting checks;
• safety device checks;
• performance measurement;
• controlled trial run;
• assessment of unusual noises, temperatures, or movements.

At Integron, you can have industrial hoses tested and certified. Following a test, a report or certificate containing technical data and results can be provided. The specific test method, acceptance criteria, and release procedure must always align with the type of installation, relevant requirements, and agreements made with the client.

What should be included in a good maintenance report?

For asset owners, it is not just important that maintenance has been carried out. Afterwards, it must also be clear what was checked, what deviations were identified, and what measures were taken.

A useful maintenance report should preferably include:

• identification of the installation;
• date and reason for the work;
• scope of the inspection or maintenance service;
• checks and measurements performed;
• deviations identified;
• parts replaced or repaired;
• test method used;
• test and measurement results;
• outstanding points of attention;
• recommended follow-up actions;
• suggested date for re-inspection;
• relevant photos, certificates and measurement reports.

This registration supports technical decision-making and makes it easier to track developments across multiple maintenance intervals.

When does preventive maintenance pay for itself?

The question is not just what maintenance costs, but primarily what risk it mitigates. Two cost scenarios can be compared for this purpose.

Costs of planned maintenance

• preparation and work permits
• scheduled deployment of technicians;
• inspections and measurements;
• parts and materials;
• testing and reporting;
• any planned production downtime.

Potential costs of unplanned downtime

• production loss;
• emergency deployment of staff and suppliers;
• additional diagnostics;
• expedited delivery of parts;
• repair of consequential damage;
• additional safety measures;
• testing and recommissioning;
• delays to other work.

Preventive maintenance is not automatically cheaper in every situation. The economic value is realised when the cost of a measure is proportionate to the probability of failure and its potential consequences.

That is why a risk-based comparison is more robust than the general assertion that preventive maintenance is always the cheapest option.

How do you make the transition from scheduled to risk-based maintenance?

A maintenance calendar tells you when work is scheduled. A maintenance strategy also explains why that work is necessary, which risk is being managed, and how the result is verified.

A mature maintenance approach therefore consists of:

1. Defining the installation and system boundaries.
2. Determining critical functions and components.
3. Identifying relevant failure mechanisms.
4. Assessing safety, environment, and business continuity.
5. Selecting an appropriate maintenance method.
6. Preparing and safely executing the work.
7. Testing the installation before release.
8. Documenting the results and follow-up actions.
9. Periodically evaluating and adjusting the maintenance plan.

In this way, maintenance becomes not just a collection of separate tasks, but a manageable process that aligns with the organisation's technical and operational objectives.

What does risk-based maintenance deliver for your organisation?

Preventive maintenance is most valuable when it is applied in a targeted manner. The focus is not on the number of maintenance visits, but on whether safety and availability risks are demonstrably managed.

This requires insight into the installation, a critical assessment of failure risks, appropriate inspection and testing methods, and clear maintenance reporting.

Which components pose the greatest risk to the safety and availability of your installation?

Together with your technical team, we can assess the installation condition, criticality, maintenance history, and available test results. Based on this, targeted maintenance priorities and follow-up actions can be established.

Contact us for a technical inventory or maintenance advice.

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