Maintenance consulting for cement and aggregates plants
Aegis provides preventive maintenance, shutdown planning and supervision, storeroom, and training services to cement and aggregates plants in Indiana and across the Midwest, led by an engineer who spent more than 20 years in those industries.
Why these plants are different to maintain
A cement plant is one continuous line. Quarry, crusher, raw mill, preheater and kiln, clinker cooler, and finish mills each feed the next, with limited storage in between. When the kiln stops, clinker production stops, and a kiln cannot be stopped and restarted at will: it has to cool before anyone can work inside it, and it is heated back up on a controlled schedule to protect the refractory.
An aggregates plant is a simpler process, but it is hard on equipment in the same ways, and it often runs through a single primary crusher with no spare line beside it.
- Abrasive material: rock, raw meal, and clinker wear out crusher liners, mill liners, chutes, screens, and conveyor components as a normal part of running. Wear has to be measured and planned around.
- Dust and heat: dust works its way into bearings, seals, and lubricant, and kiln and cooler equipment runs hot. Lubrication and sealing practice count for more here than in a clean plant.
- Large, slow, heavily loaded machines: kilns and mills run on girth gears, tires and support rollers, and large bearings and gearboxes. Faults tend to develop slowly and can be found early, but the repairs are major jobs.
- Long lead times: major components can take many months to obtain, so every decision about which spares to hold carries real cost either way.
- Work concentrated in outages: much of the heavy work can only be done with the line down, so the annual outage carries a large share of the year's maintenance. Many Midwest plants place it in winter, when construction demand is lowest.
- Conveyors and elevators with no bypass: a failed belt or bucket elevator between two process steps stops everything on both sides of it.
Experience from inside these plants
Aegis was founded in 2026. What it knows about this equipment comes from founder Cristian Boar's own career in cement and aggregates plants.
He started in 2002 with Holcim in Romania, where he built the preventive maintenance organization at the Alesd cement plant and went on to run its mechanical maintenance. In 2015 he moved to the United States: maintenance manager with LafargeHolcim US at the Paulding and Portland cement plants, reliability manager at Continental Cement in Davenport, and corporate reliability engineer for St. Mary's Cement. From 2023 to 2026 he was plant manager at Arcosa Lightweight Aggregates.
The full record is on the about page.
Preventive maintenance on kilns, mills, and crushers
In these plants a PM program rests on three things: lubrication that holds up in dust and heat, inspections that track wear before it becomes a failure, and condition monitoring on the large rotating equipment where a slowly developing fault can be caught in time. At Alesd, Cristian set up the plant's lubrication, vibration measurement, and non-destructive testing programs.
More on preventive maintenance consulting.
Kiln and mill shutdown planning
A kiln outage puts refractory work, mechanical repairs, and inspections that need a cold line into the same short window, usually with several contractors sharing the same space and one restart date. The scope has to be built from inspection findings gathered while the plant was running, and long-lead parts have to be ordered well before the stop.
Cristian has run these outages from the plant side: annual major shutdowns on all main equipment at two US cement plants, and before that a kiln shell replacement and a raw mill first-chamber liner replacement at Alesd.
More on shutdown planning and supervision.
Wear parts, critical spares, and the storeroom
A cement or aggregates storeroom holds two very different kinds of parts. Wear parts such as liners, screen media, belts, and idlers are consumed at a rate that can be measured, and should be stocked against that rate. Critical spares such as gearboxes, large bearings, and motors may sit for years, and need the right storage and care to be usable on the day they are called for. Both depend on bills of materials that match equipment which has often been modified many times since it was installed.
More on MRO storerooms, critical spares, and BOMs.
Training on your own equipment
Aegis shapes training around the plant it is delivered in. For a cement or aggregates crew that means the examples come from kilns, mills, crushers, and conveyors. As a corporate reliability engineer for a cement producer, Cristian coached and trained plant maintenance teams on reliability practices and tools.
More on maintenance training.
Not sure where to start
If it is not clear where the biggest gap is, a maintenance audit reviews planning, preventive maintenance, the storeroom, and shutdown readiness together and reports what to fix first.
Common questions from cement and aggregates plants
Does Aegis only work with cement and aggregates plants?
No. Aegis is a maintenance consulting firm for industrial and manufacturing plants. Cement, aggregates, and heavy manufacturing are where founder Cristian Boar spent his career, so they are the plants Aegis knows from the inside.
How far ahead should a kiln shutdown be planned?
Earlier than most plants start. Long-lead parts have to be ordered months ahead, and refractory and mechanical contractors are in demand during the usual outage season. A sound practice is to begin scoping the next outage when the last one closes, using its lessons and the inspection findings from the run, and to freeze the scope well before the stop date.
Can Aegis supervise a shutdown as well as plan it?
Yes. Shutdown supervision is one of Aegis's services. It means being on site through the outage: running the daily coordination, tracking progress against the schedule and the scope, and overseeing contractors through to startup.
What does preventive maintenance look like on a rotary kiln?
Most of it is inspection and measurement while the kiln runs: shell temperature, the condition and contact of tires and support rollers, girth gear and pinion lubrication and tooth wear, bearing temperatures, and the inlet and outlet seals. What those inspections find sets the scope of the next outage. Work that needs a cold kiln, such as inspecting the refractory, is planned into the outage itself.
Where is Aegis based, and which plants does it serve?
Aegis is based in Indiana and serves plants across the Midwest. Audits and shutdown supervision take place on site at your plant.