Management of DCS service life
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With the widespread adoption of DCS control systems, more and more manufacturing enterprises use distributed control systems to achieve automatic control of their production processes, and production facilities are becoming increasingly dependent on automated control instruments. Our company has been using DCS systems for over twenty years; the last two sets of such systems were phased out because the manufacturer stopped producing spare parts for them, and they had a high failure rate. The more than a dozen sets of DCS in use currently face a problem: after about 7 years of operation, their failure rate starts to increase, and what to do about this has become an issue that plagues us – they’re practically useless! My current management approach is as follows: 1. Regular inspections: For DCS systems that are 5 years old or older (or 3 years old if operating under harsh conditions), I have the manufacturer come to the site to conduct inspections, and they provide inspection reports to help determine the next steps; for the rest of the systems, self-inspections are carried out annually using the manufacturer’s methods ； 2. Timely upgrading: For control systems whose operating conditions do not meet the requirements but have a short service life, the issue is resolved by contacting the manufacturer to carry out software and hardware upgrades. How does your organization manage DCS systems that have been in use for more than 6 years (the lifespan at which controlled fixed assets become obsolete and when failures are more likely to occur)? I hope everyone will discuss and share.
We are upgrading the DCS in a timely manner. As for phasing it out, it depends on usage conditions – if it can still be used, then we will continue to use it.
It needs to be considered comprehensively; if the maintenance workload is too high, failures occur frequently, spare parts are hard to obtain, and production is affected, then an upgrade is necessary.
I think it depends on where the problem lies. If the control-level devices show signs of wear and tear, new devices can be purchased in batches; it’s not difficult to find devices that are about 5 years old. If it’s hard to obtain hardware of the same model, it’s better to upgrade the hardware while still being able to use the control programs. (I work in the pharmaceutical industry; the suggestions above are for reference only.)
Spare parts: Lol – a universal spare parts repository for the large group; all subsidiaries use the same DCS system to reduce spare parts costs. If a part is indeed phased out, it is updated uniformly
It’s easier if there are spare parts; keep using it as long as it works. After all, replacing the DCS system entirely comes at a high cost, and it’s not good to stop production either
An upgrade is a more appropriate option; in fact, the spare parts for the old system are quite expensive. The service life of imported ones is about ten years. With domestic products, there’s no need for upgrades; as long as spare parts are available, it’s fine to use them, since domestic spare parts are relatively inexpensive but of lower reliability. Reduce production costs
The service life of a DCS system cannot be simply determined by the amount of time it has been in use. The lifespan of electronic components is limited; in particular, electrolytic capacitors last around 8 years. Therefore, it is advisable to consider replacing the power supply after 5–7 years of use. It is also important to keep necessary spare parts on hand. During the operation of the DCS system, it is necessary to keep track of any upgrades available for both the hardware and software of that model. If conditions permit, such upgrades should be carried out gradually. A reasonable service life for a DCS system is 10–15 years; if costs allow, 8–10 years is also acceptable. It is recommended to conduct an inspection of the DCS system once a year starting from the 3rd year of use (if conditions permit), or whenever maintenance is performed.