AXILINEOn-site rotor balancing in Coimbra: 110 km south of our base
Your machine is in Coimbra; our base is in Vila Nova de Gaia. That is about 110 km of motorway, a little over an hour, and this is how we work: instruments in the car, the rotor balanced in its own bearings, measurements before and after. We have no branch, no workshop and no resident technician in the district, so travel appears on the invoice with the kilometres counted. In exchange, a well-prepared visit covers several machines in one day, and that is what makes the trip pay for itself.
Coimbra is 110 km from our base: what that changes
We have no office, no workshop and no staff in Coimbra. We have one base, in Vila Nova de Gaia, and a car that drives south on the A1. It is about 110 km to the city. That is what sits behind every quote for the district: a real route, counted both ways, rather than a shopfront address on a map.
A trip to Coimbra differs from a trip to Matosinhos in two ways. First, the drive goes on the invoice. Second, coming back the next day over one forgotten detail costs another drive. So we prepare these visits in more detail than local ones: we confirm in advance the access to the correction plane — the point on the rotor where the mass is fitted — the condition of the bearing housings, who does the fitting work, and what the real stop window is.
The practical consequence is simple: it is worth coming to Coimbra with a full day of work. One machine alone still pays the minimum invoice and the travel; three machines split that fixed cost three ways. If you already have a shutdown scheduled, that is the moment to gather everything on site that vibrates.
- Route: base in Vila Nova de Gaia, A1 southbound, about 110 km each way to Coimbra.
- We count kilometres by the actual road route, round trip, not by a straight line on the map.
- The same trip comfortably covers Figueira da Foz, Cantanhede, Mealhada, Condeixa-a-Nova, Penacova, Lousã and Miranda do Corvo.
- Work that runs longer than a day adds a per diem, so it helps to know in advance how many machines there are.
- We do not do late-afternoon emergency call-outs 110 km away. An agreed window is worth more than a promise of urgency.
If the machine is in Figueira da Foz rather than Coimbra, the calculation is identical — only the mileage changes. Give us the exact address and we send the travel figure in writing before we leave Gaia.
What a visit to Coimbra costs: the arithmetic
The price of the work does not change with distance. It changes with rotor size. Distance only enters the travel line, and that line is simple arithmetic you can check yourself.
For a site 110 km away with a lot of machines there is also another route: buy the instrument and bring part of the work in-house. The Balanset-1A costs 1975 EUR + VAT, the OEM version 1735 EUR + VAT. It does not replace the first visit, because the method is learned with the machines in front of you, but it handles the day-to-day without waiting for a trip.
- Coimbra is about 110 km each way, so roughly 220 km round trip.
- Of those 220 km the first 20 are included. That leaves about 200 km at 0.60 EUR: roughly 120 EUR of travel.
- One medium machine: 300 EUR diagnostics + 450 EUR package M + about 120 EUR travel, all + VAT.
- One small machine on its own: 300 + 250 = 550 EUR plus travel. It clears the 500 EUR minimum, but the drive weighs heavily on the total.
- Three machines in one visit: travel and the working day are split three ways, and the cost per machine drops sharply.
- A two-day job: 140 EUR per day per diem, and travel is still counted once, not twice.
- The exact figure for your address is calculated before the trip and fixed in the quote.
| Item | Condition | Price + VAT |
|---|---|---|
| Vibration diagnostics with report | per machine, always billed | 300 EUR |
| Balancing, package S | up to 15 kW or up to 50 kg | +250 EUR |
| Balancing, package M | 15–75 kW or 50–500 kg | +450 EUR |
| Balancing, package L | 75–300 kW or 0.5–2 t | +700 EUR |
| Balancing, package XL | over 2 t or high running speed | from +1200 EUR |
| Mass fitting by AXILINE | without welding / with welding | +150 / +400 EUR per rotor |
| Travel | first 20 km from the base included | beyond that 0.60 EUR per km, round trip |
| Per diem | when the job runs longer than a day | 140 EUR per day |
| Minimum invoice per visit | whichever package applies | 500 EUR |
VAT at the applicable rate is added to every figure. The minimum time on site is 4 hours — not a surcharge, but what the initial measurement, the test runs and the verification of the result genuinely take.
Pulp, paper and forestry: the machines of the Mondego valley
The corridor between Coimbra and Figueira da Foz is pulp, paper and timber country. Eucalyptus goes in through chippers, comes out as fibre, and drags behind it a fleet of rotating machines living in an abrasive, wet and hot environment. It is the sector in this region that generates unbalance fastest.
Almost all of these machines run continuous processes. The stop window cannot be invented: it is either a planned outage or the annual shutdown. That is why visits to this sector are agreed weeks ahead and are almost never for a single machine.
Chippers and debarking drums
The disc loses its balance with every knife set: uneven wear, one knife replaced on its own, a counter-knife seated badly. The classic symptom is a once-per-revolution knock that appears right after knife maintenance. Here balance is a consumable, not a one-off setting for the life of the machine.
Biomass boiler draught fans
Ash and salts stick to the blades unevenly, and hot gas bows the shaft. The amplitude creeps up over weeks and then jumps in a minute when a slab of deposit lets go. We measure with the machine hot and fit the masses once the casing is safe to work on.
Dryer and hood exhaust fans
Wet fibre, pitch and condensate build a deposit on the inner face of the impeller. Balancing on top of a deposit is money thrown away: the result lasts until the next layer. Cleaning first, masses second.
Stock pumps and vacuum pumps
Impellers worn by mineral fillers, fibre blockages, wear rings at the end of their life. This is where the distinctions matter: cavitation and blade-pass are not unbalance and are not fixed with masses. They show up in the spectrum and go into the report as what they are.
Cooling tower fans
A long, light, large-diameter blade with adjustable pitch, working in permanent humidity. It responds to very small masses and has to be corrected in short steps. It is always worth checking blade pitch scatter first: a blade set at the wrong angle imitates unbalance.
Agitators, refiners and drives
Long shafts, couplings, belt drives. In these assemblies vibration is rarely unbalance alone: misalignment appears, which is a cause of vibration tied to the relative position of the shafts. The corrective work in that case is shaft alignment, and that is a different job from fitting masses to a rotor.
None of this is decided at a distance. Before we leave Gaia we want the running speed, the overall level in mm/s at each bearing and, if you have it, the 1x component with phase. With those numbers we can tell you over the phone which of your machines are worth including in the visit and which are better left out.
Moulds, machining and metalworking
West and south of Coimbra lies the country of moulds and precision machining, and around the city itself there are metalworking shops, plastics injection and processing plants. In this sector vibration is not first measured on an instrument: it is measured on the part. It shows up as chatter marks on the surface, as tools wearing out fast, as a tolerance that stopped holding.
- Milling and grinding spindles: vibration at running speed goes straight into the surface finish. What gets balanced is the rotating assembly in its own spindle, not the whole machine.
- Grinding wheels: rebalancing after dressing and after mounting on a new flange is routine work, not a repair.
- Granulator and plastics mill rotors: worn knives and caked material throw them off quickly.
- Chip, dust and oil-mist extraction: impellers with an oily deposit, often hung on light roof structures.
- Compressors, chillers and condenser fans serving injection cells, almost always grouped in the same building.
- Pulleys and couplings on belt drives: an eccentric pulley produces vibration at running speed without the rotor being unbalanced at all.
An honest caveat: not every judder on a machine tool is unbalance. Chatter (self-excited vibration of the cut), play in the ways, spindle bearings at the end of their life and structural resonance leave similar marks on the part and do not improve with masses. That is exactly why the 300 EUR per machine vibration diagnostics is always billed: it is what separates the cases, and the reference methodology is that of ISO 13373.
Food and agri-processing in the Baixo Mondego
The Mondego fields, rice, the wines of Bairrada and Dão, dairy, olive oil and fruit and vegetable processing give the region a rotating fleet of its own, with one rule that changes how the work is done: in a food zone you do not weld and you do not improvise a fixing.
Rice hulling and milling
Huller rotors, whitening cones, hammers, elevators and screw conveyors. Unbalance arrives with wear on the hammer set and with partial replacement of parts. The dust is fine and combustible, which constrains how we are allowed to work on site.
Extraction and drying
Cyclone fans, dryer fans and silo aspiration fans. Organic deposit on the inner face of the impeller, humidity and seasonality: the machine stands idle for months and starts back up already out of balance.
Separators, centrifuges and decanters
Dairy and olive oil run high-speed machines with a closed bowl. Here unbalance almost always comes from product built up inside the bowl or from an incomplete clean, not from the rotor itself. The right order is clean, inspect, and only then measure.
Industrial refrigeration and cold rooms
Evaporator and condenser fans, compressors, cooling towers. Many small units of the same type in the same building — precisely the case where a trip to Coimbra pays for itself, because several get done in one visit.
Wineries and filling lines
Pumps, destemmers, drums and conveyor drives. Work concentrated in the harvest season: outside it there is a window to stop, during it there is none.
Fitting masses in a food zone
No welding, no magnetic masses left on the machine, no improvised adhesive. Stainless masses bolted through existing holes, or controlled metal removal by drilling. This is agreed before the visit, not worked out on the spot.
If the product is hygroscopic or sticky, say so in your enquiry. It changes the most important decision of the day: whether it is worth balancing now, or whether the machine needs a proper clean first. Balancing a dirty rotor hands the problem back with the next deposit.
Hospital, university and building utilities
Coimbra is a city of hospitals, laboratories and a university campus. The rotating equipment in these buildings is discreet — it lives on the roof, in the basement and in plant rooms — and it reaches us almost always by the same path: someone on the floor below complains about a hum that will not stop.
This work has rules of its own, and they are better stated before quoting. Many of these machines sit on anti-vibration mounts, that is, on a flexible support: this changes which part of ISO 20816 applies and changes how the readings are interpreted. And in a clinical area there is no welding, no dust and no improvisation.
- Air handling units, duct fans and roof fans: the nuisance travels through the structure and the ductwork, and the source is not always the rotor.
- Smoke extraction fans: tested periodically, rarely monitored, and usually in the worst condition of anything in the plant room.
- Cooling towers, chiller fans and primary and secondary circuit pumps.
- Fume hood and laboratory extraction: the chemical environment eats the impeller unevenly, and uneven loss of material is unbalance.
- Laundry and large extractors: note that an unevenly distributed load produces vibration at running speed without the rotor being unbalanced.
- Standby generator sets and fire pumps: they are only tested under load, and that is where the vibration shows.
- Working windows: night, weekend or the summer campus shutdown, with the access permit sorted out before we arrive.
If the complaint is structure-borne noise, let us measure before you order balancing. Anti-vibration mounts at the end of their life, soft foot (an imperfect seating of the machine foot on its frame), loose fixings and slab resonance explain a good share of these cases, and none of them is corrected by masses on the rotor. The applicable part and edition of ISO 20816 must be checked for each specific machine.
How a visit to Coimbra actually runs
The sequence below is not bureaucracy. On a 110 km trip, every skipped step turns into repeated kilometres, and those get paid for.
- Open access to the correction plane: an inspection hatch, a removable cover or a window in the casing.
- Clean bare metal on the bearing housings for the sensors, free of paint and dirt, so the magnet seats properly.
- A spot on the shaft or pulley for the reflective mark, with a clear line of sight for the laser phase sensor.
- A 220 V socket near the machine for the laptop and the measuring module.
- The impeller cleaned of deposits and the foot and foundation fixings checked before we arrive.
- Decided who does the fitting work: with your own people it is included; with our specialists, +150 EUR per rotor without welding or +400 EUR with welding.
- 01
Describe what needs doing
A list of machines, type, power or rotor mass, running speed, bearing and drive type, exact address. With a list rather than a single machine, the quote comes out better for you.
- 02
Send numbers and photos
Overall level in mm/s per bearing, the 1x component with phase if you have it, photos of the bearing housings and of the access to the correction plane, and a short video of the machine running. This is what prevents a wasted 110 km drive.
- 03
Get the quote with travel already calculated
Package per machine, travel by the real route, per diem if the job runs longer than a day. All of it fixed before we leave Gaia.
- 04
Agree the window and sort out access
Stops and starts, site passes, work permit, start-up lockout, fitter and electrician on shift. On a long trip the window governs the schedule, not the other way round.
- 05
The working day on site
Initial measurement on every machine on the list, mechanical checks, test runs, calculation and fitting of the masses, verification measurement at the same points and in the same regime. Anything that is not unbalance is said on site and written into the report.
Phone and WhatsApp: +351 931 831 229. Email: axilinegeral@gmail.com. Instagram: @axiline.pt. Base: Rua das Colectividades 76 R/C ET, 4430-625 Vila Nova de Gaia. For enquiries from Coimbra, WhatsApp is the fastest route: photos and a short video of the machine running say more than half an hour of description.
Frequently asked questions
Do you have a team or a workshop in Coimbra?
No. AXILINE has a single base, in Vila Nova de Gaia, at Rua das Colectividades 76 R/C ET, and travels to the customer. Coimbra is about 110 km each way. We have no branch, no store and no resident technician in the district, and we would rather say so than fake a local address: that way you know where the car sets off from and which kilometres you are paying for. The work on site is the same as we do in Porto — balancing in the machine's own bearings, without removing the rotor.
What does travel to Coimbra cost?
The rule is the same across the country: the first 20 km from the base are included in the price, and beyond that it is 0.60 EUR per kilometre, round trip. An address in Coimbra means about 220 km of driving in total, minus the 20 included: roughly 200 km at 0.60 EUR, so close to 120 EUR + VAT. If the job runs longer than a day, a per diem of 140 EUR per day is added, but travel is still counted once. The exact figure is worked out by road route to your address and written into the quote before we set off.
Is it worth calling you out for just one machine?
Honestly, that is the least favourable case. One small machine is 300 EUR of diagnostics plus 250 EUR for package S, about 550 EUR, plus roughly 120 EUR of travel; the minimum invoice per visit is 500 EUR. With three machines in one visit the fixed cost is shared and the figure per rotor drops sharply. It pays to look around: another of your plants in Figueira da Foz, Cantanhede or Lousã, or a neighbouring company with the same problem, fits into the same working day.
Can you work at night or during a planned shutdown?
Yes, and that is how most continuous plants in the Mondego valley are worked. The window is set by the site, not by our diary: we need to be able to stop and start the machine at least three times, at running speed. Tell us the dates of the planned outage or which night shift is available and we will confirm whether we can fit it. For an annual shutdown, plan the request weeks ahead and gather every machine on the list — that is the scenario in which a 110 km trip returns the most.
What if the cause turns out not to be unbalance? Do we lose the trip?
We say so on the day, with the measured numbers in front of us, rather than after a series of pointless test runs. Vibration diagnostics with a report costs 300 EUR per machine and is always billed, precisely because it is what answers that question: you end up knowing what is going on and what to do next. Balancing only reduces the 1x component. It does not correct misalignment — the corrective work for that is shaft alignment — nor bearings at the end of their life, nor loose fixings, nor structural resonance. To cut that risk before anyone drives 110 km, send us the levels per bearing and photos in advance: in many cases we can warn you by phone that a visit is still premature.
Related content
Prices: vibration diagnostics and balancing, priced separately
Vibration diagnostics for one machine, with a finding and a written report, costs 300 EUR. If balancing turns out to be feasible, it's added by rotor size: S +250, M +450, L +700, XL from +1200 EUR — a total of 550 to 1500 EUR and up per machine, in one or two planes at no extra charge. If balancing isn't possible — for example because of damaged bearings — you pay only for the diagnostics and travel, and you get a report with the cause of the vibration. The minimum invoice per visit is 500 EUR, and all prices exclude VAT.
Rotor balancing in Porto and Vila Nova de Gaia: based close by, serving the whole country
Yes — Porto and Vila Nova de Gaia are our home region, we work across the whole north of Portugal, and by arranging the schedule we travel to any point in the country. The first 20 km of travel from our base are included in the price, and beyond that it's 0.60 EUR per kilometre, round trip. The minimum invoice per visit is 500 EUR, the minimum time on site is 4 hours, payment is 50% in advance, and all prices are + VAT. We work out the exact amount for your address by route and send it before the visit, so there are no surprises on site. Send us the machine type, running speed, power or rotor mass, and a couple of photos of the unit on WhatsApp +351 931 831 229, and we'll tell you whether balancing will actually help here.
On-site rotor balancing, in the machine's own bearing housings
On-site balancing means the rotor stays in the machine. We fit two accelerometers (vibration sensors) on the bearing housings, aim a laser phase sensor at a reflective marker, take the initial vibration reading, run one or two trials with a weight of known mass, calculate the correction mass and angle, fit the weights and measure again. You get a report with the figures before and after. A typical visit takes a working day; vibration diagnostics with a report costs 300 EUR per unit, balancing adds from 250 EUR, and the minimum invoice per visit is 500 EUR.
Describe your equipment and the problem
We'll answer your questions, clarify the details, and let you know what's needed for an estimate and a visit.