It is our pleasure to let you share a part of our knowledge by publishing articles about construction equipment and business best practices.
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Avoid high ambient temperatures and save money !

Due diligence and equipment risk

Why the use of 100% oil free compressed air?

New concept in the European market of oil free compressed air rental

Giant DTH drill on foundation project

Equipment need : Buying versus Renting

TIPS and TRICKS to energy savings in compressed air systems.

Why dry compressed air is so important

The Used Portable Compressor Market in EMEA

100% Oil Free Compressed Air for Rental in Europe

Compressed Air Energy Storage (CAES)

PRESS RELEASE New Player in the market of high pressure portable compressors

Making money with your old machines

Daily machine inspections can reduce downtime

If you want to know more please :


Avoid high ambient temperatures and save money !


During the summer period operation costs for compressed air installations unnecessary rise. Due to high ambient temperatures in the compressor room the efficiency of compressors and dryers are decreasing dramatically. At the same time the numbers of technical failures are potentially increasing.

A temperature rise of 10 ° C reduces the compressor efficiency by as much as 3%, and has a negative impact on the service life of the compressor oil, which may lead to unnecessary maintenance. The refrigeration dryer efficiency even drops to 30%!

Most of the failures of refrigeration dryers occur during hot days, the dryer has to cool much harder than usually which increases the change of a breakdown or not reaching its full capacity.

Optimising your compressed air room is the answer. Small changes often deliver great improvements.
If you require independant advice or just a second opinion, please contact us.

Compressed air room 1

For more information simply contact us


Publish date: 29-08-2016 

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Due diligence and equipment risks

You are considering to buy a company with a fleet of equipment ?

Is this fleet a considerable part of the assets of this company ?

You should perform a due diligence investigation. Part of this investigation are equipment inspections.
These inspections are most important to know the actual condition , position and value of the assets as a part of the due diligence. Book value of assets is in most cases an unreliable method of determining the value of your assets, after all it is value on paper or in a system. In most cases depreciated over time or in function of yearly results.
In practice, many parties have a stake in this process and these results. This gives a blurred image of the financial situation of the company.

This could cost you a fortune.

Do not take such a risk and rely on independent equipment inspection. Combined with decades of residual value expertise, RTC Group is the right party to do both. Both equipment inspections and residual value expertise.

Equipment categories:
*Construction equipment
*Mining equipment
*Earth moving equipment
*Road machinery equipment
*Drilling equipment
*Material handling equipment
*Industrial equipment

Regions: Anywhere in the world

We offer you:

 detailed inspection report with hundreds of items checked
 condition notes supported with pictures
 residual value report based on actual market conditions
 concise executive summery to have a categorised overview in case of large fleet
 transparent communication
 conclusions and recommendations

For more information simply contact us


Publish date: 16-04-2016 

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Why the use of 100% oil free compressed air?

The use of compressed air is very common in many companies and industries.Compressed is a utility like electricity and natural gas. Compressed air is a safe form of energy. It runs processes and tools in small garages , in medium size factories and in large industrial companies. Generating compressed air is an expensive activity. So far all very understandable.

But what about oil free compressed air?

First be need to understand that air generated by a standard piston or screw compressor always contains a residual amount of oil (0.01 – 0.1 mg/m³). This oil contamination can ruin a production process. Industries like food and beverage, pharmaceutical, chemical and petrochemical, semiconductor and electronics, automotive, textile yarns and fibers, specialty gases, paper, glass manufacturing , they absolutely do not want any amount of improper oil contaminant in their production process. That is why these industries use oil free air even though it is very costly to generate.

What is oil free air exactly?

Oil free compressed air is generated differently than regular compressed air. The process of compressing air is done without the injection of oil or without lubrication with oil. In fact the oil does not mix or touch the air while being compressed.

The standard in compressed air oil residue is described in the ISO standards. The particular standard is ISO 8573-1 (year 2010). It describes 5 classes (0-4), where class 4 is the lowest standard (<5mg/m³) and class "0" (zero) is the highest and the purest. Class "0" is in fact specified by the user or supplier but it is for sure more stringent than class "1" (<0.01 mg/m³).

Technical oil free compressed air ?

This is air where oil is filtered out from a regular oil injected compressor. It is different than 100% oil free air from an oil free screw or centrifugal air compressor. Normally this technical oil free air is not used in applications where there are critical standards.

10425 2007 NL 001 20160107 141440-1 700x400

Temporary oil free compressed air ?

Compressed air as a temporary replacement for existing installations, during major overhaul projects or for peak demand in existing compressed air systems is not an easy task to fulfill. Investing in such capital equipment is never economical. Therefor you need to rely on rental equipment.
RTC Group supplies emergency replacement air in case of failure of compressed air equipment and for planned overhaul projects. We make renting oil free compressed air in large capacities an easy and affordable job.

Electrical driven or diesel driven, we calculate free of charge the most economical solution. RTC Group supplies oil-free diesel powered portable compressors as well as electric oil-free air compressors in various sizes and specifications. Starting from 20 m³/min [700 cfm] to over 600 m³/min [21.000 cfm]. Pressure range 2 to 11 Bar(g) – 30 to 155 psi(g). All 100% oil-free !



Publish date: 08-03-2016 

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“New concept in the European market of oil free compressed air rental”

Vroomshoop The NETHERLANDS, Today a new concept is launched in the industrial market for oil free rental compressors. A young business in the Netherlands launches a unique oil free rental machine for the European market.

RTC Group is already a leading provider of specialised rental solutions for construction and drilling.
The company now supplies competitive and low cost alternatives to professionals who are in urgent need of oil free compressed air in large volumes. “We are specialized in large centrifugal compressed air rental solutions” says Managing Director and owner Henk Uphoff.

The containerised package consists of a 530 kW (725 HP) oil free centrifugal air compressor, refrigerant air dryer and all the necessary auxiliary equipment to start and operate the package on its own. With a capacity of 4200 m³/hour ( 2400 cfm) and a pressure range from 5 up to 11 bar this machine is unique in the market. Regular diesel driven compressors are half the capacity and burn easily 15.000 litres of diesel fuel per week.

Oil free C70 air compressor for rent

Needless to say, the loss of compressed air supply can put your facility completely out of production. Flexibility and quick response time is critical in many industries. “Our equipment can be on the move to the customer within hours of the first emergency call” according to Mr. Uphoff. This makes both size of the equipment and fast response, Europe wide, to a unique concept.


Publish date: 01-03-2015 

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Giant "Down The Hole" (DTH) drill on foundation project

powered by RTC Group

RTC Group has secured a rental contract for the supply of 2 pieces 600 HorsePower high pressure diesel driven air compressors. The project is taking place as a part of the enlargement of Stockholm's passenger ship harbour.

Danish contractor who is operating this project has called in the help of Swedish drilling equipment supplier to engineer this special drilling method. A huge air powered down the hole drill (DTH) is taking care of drilling cases of 84.6 cm in diameter. All of this mounted on a Bauer BG46 drill rig which is floating in the harbour on a barge.

The drill is operated by high pressure compressed air of in total 66 m³/min at 25 Bar, powered by 2 pieces Ingersoll Rand (Doosan) 25/330 portable air compressors supplier by specialist rental from RTC Group in the Netherlands.

foundation drilling project Sweden


Publish date: 18-10-2014 

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Equipment need: Buying versus renting

When you are in need of equipment for your company or a project it is not difficult to get offers from different dealers or manufacturers. They all have the best product , the cheapest or with the best productivity. But when it comes to acquiring such piece of equipment many do not know the (financial) consequences of it. We explain the difference between buying new, buying used, leasing and renting.

Financial consequences

We are not touching the subject “maintenance” nor “cost of ownership”. We just briefly touch on the pros and cons of buying versus renting. It does have consequences for your business.

Buying new

When buying new equipment , for sure, you have the full attention of your local dealer or manufacturer. These companies prefer to sell new equipment. New equipment is expensive but has indeed a couple of advantages of buying.

  • Dealer / manufacturer support
  • Parts availability guaranteed
  • Can be customized to your needs with factory fitted options
  • Warranty (sometimes up to 5 years)
  • Image to your clients (looks new and good)
  • Pieces of mind (assuming new equipment has less downtime)
  • State of the art product latest (emission) innovations

Disadvantages of buying:

  • Expensive and sometimes difficult to raise funds
  • Delivery time (large equipment is generally not produced for stock)
  • Capital expenditure puts a strain on your cash flow and working capital

Leasing new

As an alternative to buying new and to overcome the disadvantages you could lease your equipment. There are two sorts of leasing , “operational lease” and “financial lease”.
Operational lease is using the equipment shorter than its economic life. After the lease period it still can be used and the possibility exists to take ownership for a certain amount (residual value).
Financial lease is just financing the equipment over a period of time as long as its economic life. After the financial lease period the lessee becomes owner of the equipment.

Advantages of leasing:

  • You have new equipment at your disposal
  • No residual value risks
  • Working capital is not affected and can be used for other important business
  • You can depreciate the equipment and lower your net business result (fin. lease)
  • Clarity in your cost structure, no surprises, “off-balance” (oper. Lease)

Disadvantages of leasing:

  • Delivery time can still be an issue
  • High expenses when terminating the lease contract premature
  • In the end , borrowing money costs money

We have not discussed Leasing used equipment. This is under certain conditions possible.

Buying used

For those who do not have the capital strength to buy new and cannot get a leasing or simply do not want a new machine for any other reason, there is the possibility to buy a used piece of equipment. Of course it comes with advantages and disadvantages.


  • Cheaper to purchase, no financial restraints from the bank or lease firm
  • Available immediately


  • No warranty in most cases
  • Age, hours, looks , it remains a used machine with less image on the jobsite

Make sure you know your equipment before buying used. Independent inspectors can help you.


In most cases the decision to rent a machine has to do with the length of a project. In case you do not know if the equipment will be used after a project for the following project it can be smart to rent a machine.


  • Renting is reliable
  • Available immediately
  • No investment
  • You have almost new equipment at your disposal
  • No residual value risks
  • Working capital is not affected and can be used for other important business
  • Clarity in your cost structure, no surprises, “off-balance”


  • In the very long term it is very expensive and one should consider leasing or buying

Without any doubt there is more to say about buying versus renting. This differs from case to case. Should you want to know more about it or want some expert advice in your particular case, you can contact RTC Group submit your needs.


Publish date: 18-08-2014 

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TIPS and TRICKS to energy savings in compressed air systems.

Compressed air is the fourth utility used in industry after electricity, water and gas. The electrical energy used to drive air compressors, equals to almost 10% of all the electricity used in all industrial countries and with the cost of electricity, continuing to rise, the financial stress on industry is continuing to rise too. By improving the efficiency of a compressed air system, significant energy savings are achievable.

BOGE industrial compressed air system

But first some facts.

  • Compressed Air production is in many cases the biggest energy cost for industries.
  • Leakages from old systems (and even some new) are often 25% or more of output.
  • Many compressed air systems run at much higher pressure than actually needed.
  • A rule of thumb is that every 0.5 Bar increase in pressure requires an additional 3.5 to 5% in operating costs

Compressed Air System tips

  • Ensure compressor output is matched to demand.
  • Reducing system pressure will reduce leakage.
  • Utilise the lowest acceptable pressure - reducing by 1 bar will save approximately 7% - 10% energy costs.
  • Use the waste heat from an air-cooled compressor for space heating or water heating. (4%)
  • Carry out regular system checks for leaks (see our article on measuring HERE) 16% !
  • Isolate machinery with valves to prevent leakage when not in use.
  • Maintain downstream equipment like filters. Blocked filters can cause huge pressure drops.

More tips ? , contact us today


Publish date: 18-06-2014 

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Why dry compressed air is so important

The term for the amount of water vapour in air is called humidity. Just to be clear, “humid air” is not the same as “moist air” (which is a mixture of water vapour and other substances or particles in the  air). Humidity is defined in terms of the water part of this mixture, it is called the "absolute humidity". It is commonly referred to as relative humidity, expressed as a % (like on household humidistats). It is called relative because it measures the absolute humidity relative to the maximum. Imagine a cube of 1 metre by 1 metre by 1 metre filled with air. The temperature is 16°Celsius, and the weather is fair. That cube contains one cubic metre of air, which is also saturated with water vapour.

Let’s say you have an air compressor in your company and you need air at 7 bar to use your equipment or air-powered tools. Your air compressor will suck almost 8 times (7.8) the cubic metre of air into the compressor to produce 1 cubic metre of air at 7 bar. And it will also suck in all the water vapour contained in those 8 cubic metres.

Compressed air drying

A funny fact about air is that, when it is compressed, it will still hold the same amount of water vapour found in the free air at atmospheric pressure. This means that in the cubic metre of compressed air at 7 bar, there is 7.8  times as much water vapour than the air can hold. The rest condensates and becomes water. Gravity causes it to settle in the lowest and/or coldest sections of your air system.

The liquid water can be drained from the system where it first occurs, but as the compressed air is further distributed to different points of use, more water will be condensed to its liquid form since the air is further cooled. This condensation dissolves contaminants as it passes through air lines, and forms a corrosive residue in the air piping system  and air-powered tools. This residue can also clog filters and small passages in air-operated devices.

The final result of water in compressed air systems is

  • production downtime,
  • excessive maintenance requirements,
  • premature equipment failure/replacement... 

These all lead to costly repairs. Elimination of water in compressed air systems is easily achievable with the proper equipment.

More information ?


Publish date: 22-03-2014 

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 Complete overview of the used portable air compressor market in Europe, Middle-East and Africa

RTC Group finalises the ultimate overview of the used portable air compressor market in EMEA.

A full overview of the entire used portable air compressor market in EMEA (Europe Middle-East and Africa, complete with graphs, tables and recommandations is the result of more then 15 years of experience in this niche market. Interesting facts and figures that gives detailed understanding of all dynamics in this market. Information about its main players with details and figures. Manufacturers, rental companies, traders, brokers and auctioneers are mentioned in this report.

"Everything you wanted to know about this market and its dynamics, including lots of historical information" says Henk Uphoff author of the report and Managing Director of RTC Group BV in the Netherlands.

REQUEST your copy of this "must have" report.

PDF download report      Used portable compressor report       Used portable compressor report 2


Publish date: 03-03-2014 

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100% Oil Free Compressed air for Rental in Europe

Compressed air for Rental is not new and neither is oil free compressed air for Rental. But now there is competition for Atlas Copco. RTC Group from the Netherlands offers aircooled diesel driven compressed air compressors producing 100% oil free compressed air.

180 m³/min (11.000 m³/hour= 6500 CFM) available for rent. Mostly for replacement air where oil free compressed air is critical. No longer depending on 1 supplier but an independent player in this market.

Have you become curious ?

Oil free diesel compressor for rent
Call us for more information and ask for Henk Uphoff

Publish date: 23-02-2014 

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Compressed air energy storage (CAES)

Compressed air energy storage (CAES) is a way to store energy generated at one time for use at another time. At utility scale, energy generated during periods of low energy demand (off-peak) can be released to meet higher demand (peak load) periods.

Conventional compressed-air energy storage uses a compressor to pressurize air and pump it into underground geological formations. The first two plants of this type put into operation—one in McIntosh, Alabama in 1991, and the other in Huntorf, Germany in 1978—use salt caverns as storage tanks, pumping compressed air in at night, when energy demand is lowest. During the day, the air is released, heated with natural gas, and forced through a turbine to generate power. The appeal of this technology is that it’s relatively low cost and can store many kilowatt-hours of energy.

Centac Centrifugal air compressor installation at work











 Publish date: 06-12-2013 

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“New” player in the market of high pressure portable air compressors.

NETHERLANDS, A new player in the market of high pressure portable compressors has been reported. Despite being a young business, there is more than 25 years of compressed air experience in this company.

RTC Group is already a leading provider of used equipment and top quality business consultancy. RTC Group now supplies also competitive and low cost alternatives to professionals who are in need of construction equipment. “We are specialized in large and high pressure portable compressors up to 35 Bar and rock drill equipment” says Managing Director and owner Henk Uphoff. Not a new name in the international compressed air business. Henk Uphoff has been working for and with the leading manufacturers of air compressors and is a well-known name in the market of used construction and mining equipment.

“We are a small, well experienced organisation with low overhead, providing the most economical and highest quality offer to enable our customers to reach maximum productivity”, according to the company owner.

Today’s expansion of its specialised rental and trade portfolio is a 35 (!) Bar Atlas Copco portable air compressor , the XRYS 577 CD ( DrillAir ) with powerful 429 kW (583 HP) C18 Caterpillar diesel engine. There is also a vast availability of 25 Bar portable compressors of different brands available for rental.

XRYS 577 drillAir   high pressure portable compressor






Publish date: 01-11-2013 

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Making money with your old machines

The capital within an equipment rental fleet is in my opinion, a "hidden treasure" of possibilities. By looking at the fleet from a different prospective, I see something else then just machines. I see a Remarketing opportunity beyond your belief. A fleet reorganization, selling old machines, will bring in more money that you can use for reinvestment in equipment, additional profit or to pay for your other investments.

But not just selling your old (intensive care) machinery is possible. Also machines that have (too) low utilisation, are eligible to sell second hand (desinvestment). Machines with little or no utilisation just costs money. Your machines are older and less valuable so they should be written off without any benefits in return. By selling them you avoid obsolescence and generate cash flow.

 Often, you will have in your fleet machines that came in from a merger or acquisition. Problem is that there are many different brands of the same type of machines in your fleet. That brings more complexity in your maintenance program and result in higher parts inventory and higher cost. Restrict the number of brands is the advice. "And the rest?", desinvest !, so sell your second-hand equipment and make money! You can earn a lot of money for your company as owner or fleet manager.


Publish date: 06-06-2013

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Daily Machine Inspections Can reduce Downtime

Performing daily machine walk-arounds often fall somewhere between wearing your seat belt and getting the oil changed in your car. You know you should – you know you need to – but somehow it doesn’t always happen. However, daily machine walk-around inspections are vital to the overall maintenance health of your equipment fleet and can prevent costly downtime by catching minor problems before they become serious issues.Daily machine inspection on jobsite

Some equipment, such as motor graders,
excavators, loader and other earth moving equipment simply require you to check the oil in the engine crank case, empty the air cleaner precleaner if full, and check the coolant level in the radiator on a daily basis, with more extensive inspections once a week. Other machines, like a mini excavator, require lubrication, testing, draining, and visual inspections in a wide variety of areas. Air compressors need to be checked daily on coolant level, engine oil level and compressor oil levels.

 If you have a fleet of machines, how are you supposed to remember all of these items?
Yes, you should because remember , you save money in the long run.


 Publish date: 05-05-2013

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