Reefer trailer technology overview: CGS

Coldstores Group of Saudi Arabia (CGS), a 46-year-old Swiss-Saudi Joint Venture, knows which solutions are most cost effective in the demanding Middle Eastern and African climates. CGS is well recognised throughout the region for its engineering competence and capability to offer best in class Total Cost of Ownership customer solutions.

A significant change for CGS, in recent years, has been the implementation of a divisional structure.

This, according to CGS Group CEO, Peter Färber, who assumed strategic and operative responsibility for the business in 2018, creates a more in-depth focus on specific product lines.

“As a result, our customers benefit from enhanced application expertise and our direct sales force can be true consultants to our customers,” he said. “Sharing of best practices across regional boundaries has become easier and enables CGS to be a continuously learning company.”

Another notable achievement for the Saudi-based business is its progress with Industry 4.0.

“CGS is implementing a clearly defined roadmap to automate processes and main production lines,” he said. “Besides implementing new software solutions, we invest significantly into cutting edge technology such as laser scanning, 3D printing, laser CNC, industrial and collaborative robots. Our latest endeavour into Virtual Reality (VR) helps us to enhance customer experience during concept prototyping. All these investments enable us to consistently deliver a superior quality product and produce with higher throughput flexibility. It also makes CGS a very attractive employer.”

During the Covid pandemic the business adjusted its operational practices several times.

“All our employees have proven to me how agile they are,” said Färber. “I was really impressed by their demonstrated crisis management capabilities.”
The opening of a new Riyadh Service and Maintenance Centre in 2019 is a purpose-built state-of-the-art facility that is easily accessible for CGS customers and has significantly increased the OEM’s service capacity.

“We have accelerated product innovation over the last few years and patenting is ongoing,” said Färber. “But to highlight a few, CGS is the first company in the Kingdom to produce Freon compressor racks for refrigeration applications, we developed a new van insulation based on 3D scanning and we just launched our Total Protection Plan which covers cooling units with a three-year warranty provided that the required service intervals are done by CGS.”

CGS EXPO2022 was the first event of its kind and was held 20 November 2022.

The OEM stands out in the trailer manufacturing market in the Middle East, particularly as a preferred supplier, because the Total Cost of Ownership (TCO) matters.

“We do not believe in reducing cost at the expense of lower quality or higher maintenance costs,” said Färber. “Our customers do understand that the initial price paid is only a small part of total operating costs. Our engineering capabilities are second to none in GCC. We are able to fulfil the highest customer requirements with tailored solutions.”

In Saudi Arabia, the total weight of trailers and trucks is automatically checked via axle sensors and the information is uploaded to a government portal. CGS is able to produce the lightest trailer in GCC thanks to engineering skills and robot welding.

“Our production process enables CGS to manufacture high-quality trailers consistently,” said Färber. “Customers trust in our competence and capabilities. We are ISO 9001 certified and in process of ISO 14001 and ISO 45001 certifications.”

The extreme heat in KSA requires many temperature-controlled transport solutions. CGS is the local leader in production of reefer trailers.

“We operate a globally unique open pouring plant, developed in partnership with KrausMaffei; it is the largest plant of its kind in the world and has been upgraded to comply with the Montreal and the Kyoto protocol requirements,” said Färber. “The ambient temperature does not affect our panel quality and CGS is the only local company that uses this technology. We produce sandwich panels in Saudi Arabia since 1991 and have sufficient experience to cope with the demanding environment. All of this gives our customers investment and asset protection.”

So, what makes CGS special? Well, Färber said it is CGS’ employees. “We call it the ‘CGS family’ as a reflection of how we treat our employees. Many of our employees are multi-skilled meaning they are competent in performing different task. Our leaders operate an open-door policy. They are accessible and hands-on, they care deeply about quality and customer service. All of them are experts in their relevant field of responsibility which helps us to identify and address issues in a pro-active manner. Our employees and leaders are used to an ever-changing environment. This allows CGS to implement improvement ideas and new technologies quite quickly and without much resistance. Customers benefit by receiving a superior solution for their challenges.”

Last November, CGS held its first ever exhibition. It is using EXPO events to showcase innovative new products, customer segment specific solutions, CGS engineering competence as well as automation activities in manufacturing.

“At the same time, we celebrated our 45th anniversary that we reached in 2021,” said Färber. “The amount of international and national representation was very impressive. Among others, we could welcome a Deputy Minister of Industry from the Saudi Government and the Ambassador of Switzerland to Saudi Arabia. It was also a special occasion for celebrating long service awards with our employees.”

Meanwhile, CGS continues to refine its customer service and provides superior refrigeration and transport systems.

“Generally speaking, we tend to meet or exceed promises given to customers,” said Färber. “We invest a lot in reinventing ourselves; I mentioned before our focus to continuous improvement and adapting to new technologies. Our mentality is influenced by Swiss engineering excellence, partly due to the company’s roots. Of course, we are also looking for innovative solutions around the world and try to adapt them to the GCC market needs.

CGS is the Carrier Transicold distributor in Saudi Arabia. Our reefer bodies are optimised to work with Carrier cooling units and Carrier works together with CGS to adopt their cooling units to our local environment. Operating in ambient temperatures of up to 55 degrees Celsius and where sand is always in the air is a demanding task for both the reefer body and the cooling unit. Only professionally trained and competent people can ensure that the life span of a reefer trailer / cooling unit is meeting customer expectations. This is where CGS excels; we invest a lot in training and education to safeguard customer investments.”

A technical deep dive into CGS trailer manufacturing

Trailer chassis
CGS can manufacture semi-trailers bodies for reefer applications up to 16.2m in length for GCC and Africa. The chassis is fabricated from either standard or from pre-fabricated high strength steel profile, resulting in a light weight trailer with increased payload.

The chassis can be produced as a single piece or in a modular concept being bolted together to create the required length. A modular concept allows for quick and easy repair and enables CGS to apply just-in-time assembly.

Overall length, width and height is adjusted according to Saudi traffic regulations, while crash barriers and rear bumpers are fitted according to Saudi Standards, Metrology and Quality Organisation (SASO) requirements. CGS is also a SASO certified company to supply accessories on trailer chassis. Other specifications for different countries are produced based on customer and country requirements.

The Reefer trailer body
The selection of optimal skin material for reefer body sandwich panel walls is based on the goods to be transported. Different transport applications might require a different solution to meet legal and/or environmental needs.

The skin thickness provides impact resistance and body strength. In the Middle East the skin is exposed to a harsh climate such as sand storms, therefore needs to protect the insulation against skin erosion. Skin erosion leads to vapour penetration. CGS uses for most applications a sheet metal due to the superior characteristics (see below), with a zinc and paint coating thickness of at least 20 microns each. PVC coated steel skin is available for food safe applications.

Skin options
Glass Reinforced Plastic (GRP): GRP can be a lightweight option but only, if no wood is used to bond the GRP skin. Physical properties of GRP negatively impact total cost of ownership in the GCC region and even globally the trend is overwhelmingly towards using metal skin.

Metal:
This is the most common material that is used in reefer bodies around the world. It has significant advantages over Glass Reinforced Plastic skin (GRP).

Advantages of Metal over GRP skins:

  1. Penetration resistance
    Ball diameter of 20mm, forces up to 30kg do not cause any lasting deformation.
    As a consequence, the skin will less likely need to be repaired hence reducing maintenance costs.
    
  2. Vapour tightness
    Steel surface layers are absolutely vapour diffusion tight. Consequently, loss
    of insulation properties or payload through the absorption of moisture in the insulation will be avoided.
    
  3. Corrosion resistance
    Chemical, physical protection by zinc/steel cathodic effect.
    
  4. Abrasion resistance
    Metal is far superior to GRP for abrasion from elements such as sand.
    
  5. Chemical/biological behaviour
    Resistance to commercial chemicals, resistance to rotting and decay.
    
  6. Thermal expansion
    The thermal expansion coefficient of steel is about 50 per cent less than aluminium and 70 per cent less than GRP. Thermal expansion can influence de-lamination.
    
  7. Compression strength
    Only 10 per cent compression at surface load of 500kg/m2.
    
  8. Thermal capacity
    Steel surface layers have a much lower heat storage capacity than fibre which results in the vehicle interior requiring less time and energy to cool and hence saves operating and servicing costs of cooling units.

Popular panel manufacturing methods
A variety of sandwich panel manufacturing technologies are being used around the world in this industry, each has its own advantage and disadvantages.

  • Closed Injection:

Most common manufacturing process is closed injection system. In this method, inner and outer skin are placed in the press and chemical is injected into the mould under the closed press. The main disadvantage of closed injection technology is existence of air traps and inconsistent foam distribution resulting in non-optimal material properties.

  • Open pouring:

Open pouring is the latest technology used by market leaders, where one avoids all the disadvantages of closed injection. The outcome is one single piece of insulation panel, free of air traps and produced to a uniform density that meets the optimal requirement range hence saving operating costs. With open pouring technology one can produce a consistent quality regardless of panel dimensions.

  • Lamination:

In this manufacturing process, panels are produced by laminating different layers and materials. This process utilises blocks made of Styrofoam or PU Foam. Panel structure and insulation integrity is exposed to the risk of inconsistent lamination. This manufacturing process is mainly suitable for floor and special reinforced panels.

Different types of insulation:
There are variety of insulation chemicals that are being used in refrigeration industry.

  • Polyurethane (PU) foam:

As the most popular insulation, polyurethane offers the least thermal conductivity (Better Insulation Performance) compared to other insulation materials.

PU foam is mixing polyol and isocyanate. The chemical reaction is influenced by how the chemicals are stored and mixed. Engineering starts before the chemicals even enter the mixing chambers, foaming preparation is a continuous and ongoing process that is one of the leading contributing factors to the quality of the sandwich panel.

Maintaining low porosity within the panel directly leads to a higher foam density. A more tightly packed foam means lower thermal conductivity (K-Value or λ-Lambda) which means less insulation efficiency. As a consequence, the cooling unit will have to work harder and for a longer period of time which leads to higher operating and maintenance costs.
Producing a high-quality panel with PU insulation is a process that requires skills and experience. CGS has mastered this complex process and can offer a 10-year warranty on panels.

  • Extruded polystyrene (XPS):

Commonly referred to as Styrofoam. This material is usually manufactured in the form of pre-extruded panels or sheets. These panels are suitable for flooring applications where higher rigidity is required without sacrificing your products insulation requirements.
Physical requirements a reefer body must fulfil:

  • Reducing energy transfer between ambient and transport temperature

The insulation capabilities of a body is measured in what is called the K-value; the lower the K-value the less energy is lost. The cooling unit will have to work less which means less fuel consumption and less maintenance requirements for the cooling unit. This factor is even more important in areas with high ambient temperature such as the Gulf region or African subcontinent.

The role of the reefer body is to keep the products fresh or, in case of pharmaceutical goods, keep them still working effectively. Food wastage can be reduced and the food brand benefits from better reputation which should increase customer’s revenue.

CGS customers choose our products because they care about their brand reputation in the market and because they understand the cost of food wastage

The K value must be according to international standards. The maximum value for two different types of reefer bodies is given below:

  • For chiller the optimum K-value must be less than 0.7 W/m2-k
  • For freezer the optimum K-value must be less than 0.4 W/m2-k

• Maintaining the k value
How a refer body is assembled influences how long the thermal efficiency will be maintained. In order to achieve and maintain a high sealing integrity, the following aspects are crucial:

Water proof rivets, single piece of border and kickplate profiles, rubber profiles, type of lights are all determining factors and are playing a vital role in achieving the sealing requirements.

Proper joint shape combined with the right material are key to achieving the best sealing performance.

Glue is playing a vital role in achieving the sealing requirements. Over time, the thermal efficiency will be significantly reduced and weight of the water will reduce available payload if moister is absorbed in the panel. CGS Reefer Trailers and Truck bodies are carefully designed to avoid such a negative impact.

• Structural integrity of the body
The structure must be designed in such a way that they can bear the cargo load in static and dynamic conditions. Acceleration, sudden brake, U-turn, lane changes and road conditions put stress on the body causing deflections. The structure should be able to absorb these forces and must stay in elastic limits defined by international standards. Key influencing aspects to structural integrity are:

  • Panel properties (Joints, thicknesses, etc.) determined by the static and dynamic loads on the body. Optimised for ideal conditions.
  • Floor designed according to the application (GRP, Alum, T-section) and loading (Forklift) operation, without sacrificing insulation.
  • CGS bodies are assembled by gluing, which offers an advantage over mechanical fixations like riveting, screwing, and bolting which are prone to failure under repetitive stresses.
  • Other remarks:

The GCC and Africa environment is demanding on metals and rubber used for door seals. CGS bodies uses stainless steel for locks and rivets and all materials used are carefully selected and tested before accepting them into its manufacturing process.

CGS customers know that they have selected the product with best in class ‘total cost of ownership’. There is a reason why leading brands trust CGS products and solutions.

Industry 4.0 and CNC machines
CGS commenced its transformation journey a few years ago according to CGS Group CEO, Peter Färber. “Our end vision is to have a fully automated production with AI driven production planning. We started with a shopfloor control system that gives us full visibility of all our shopfloor activities. This not only enables us to identify best practices and potential training needs, but also helps us to set investment priorities. Our laser CNC centre and our industrial welding robot are able to communicate directly with our engineering software and are integrated into our production network. This eliminates potentials for human errors and provides us with a responsive production concept. We are integrating collaborative robots into our manufacturing process where autonomous solutions would limit our flexibility. Machine-to-machine communication is one of our key focus areas and the next automation investments are already in the design phase. Automation is a complex and demanding topic but it is also a very exciting one. Innovations evolve rapidly and come from all areas of the globe. It is nearly impossible to maintain visibility of the tools available but we were fortunate to work with McKinsey on identifying the best solutions for our needs. Our automation journey very much support Vision 2030 for Saudi Arabia to become a regional manufacturing powerhouse.”