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Strong points
 Research and development
As well as using the latest heat exchanger thermal
simulation software available on the market, Nordon
Cryogénie has developed its
own software: ProSec.
This software is the result of nearly 20 years investment in R&D and tests validating the performance and operation of Nordon
Cryogénie heat exchangers on site and in the laboratory. It can process increasingly complex designs with excellent reliability to optimize our response to customer requirements. What is more, as well as performing static computations, ProSec can simulate the operation of heat exchangers in dynamic mode. Thanks to these calculations in transient conditions, we are able to validate options for startup, shutdown, operating changes and failures, in order to determine thermomechanical stresses affecting our equipment's integrity.
We maintain our position at the forefront of technology by continuous investment in R&D and collaboration with universities, engineering schools and laboratories. Projects currently being developed include:
 On-going development of 3D simulation in ProSec;
Development of the hydraulic simulation of heat exchanger batteries to assess distribution allowing for heat transfers in the heat exchangers.
The engineers at Nordon Cryogénie can choose from a range of fins in order to reduce total installation costs for the customer while ensuring dependable compliance with specifications. For this purpose, the fins are tested to measure their pressure drop and their heat transfer. Above all, these tests are conducted on brazed fins so that the results obtained are truly representative of actual performances in the heat exchanger.
Furthermore, the quality of fins is guaranteed by
measuring their pressure drop during manufacturing, as
well as conducting geometric and micrographic inspections.
Using our performance models, our engineers can assess the benefits of new fins which could be developed to satisfy customer requirements.
Manufacture
Brazing the matrix is undeniably one the key phases of the heat exchanger manufacturing cycle.
Proper control of this operation is vital for the matrix’s mechanical integrity (pressure resistance) and leak-tightness, and these two requirements are paramount to ensure correct operation of the heat exchanger in the operating conditions specified by the customer and in compliance with the applicable construction code.
Nordon Cryogénie has always done everything in its power to ensure complete control of this operation. To this end, Nordon
Cryogénie started by equipping its two vacuum brazing furnaces, one after the other, with a special regulating system in order to achieve predictive control under stress of the brazing thermal cycle, by mapping the actual temperature of the heat exchanger at every moment of the brazing operation.
Based on the breakdown of the heating elements into more than 65 separate areas, this regulating principle automatically adjusts the individual power on each furnace resistor in real time so as to obtain the shortest possible brazing time while ensuring compliance with all the essential criteria such as temperature levels and/or vacuum quality.
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Simulation of a thermal cycle before brazing.
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A further step forward has now been achieved with the development of new 3D simulation software, which can simulate the entire thermal cycle for the brazing of the heat exchanger to be manufactured. As a result, on the basis of a radiation and conduction calculation, this package, integrating all the regulating logic, optimizes the programming of regulating parameters before brazing according to the exact design of the heat exchanger and the actual brazing configuration.
As well as being systematically used during manufacture, this software also represents a technological breakthrough for Nordon
Cryogénie, especially as regards R&D, as it can be used to optimize the design of matrices (cross section, etc.).
On-Site Technical Assistance
Our On-Site Technical Assistance department has built up considerable know-how in the course of its long experience of assistance operations during plant construction and shutdowns all over the world.
Thanks to its knowledge of every detail of the work to be carried out, it skilfully organizes all aspects of the work it undertakes, including both the resources to be implemented and planning. Preparing a precise plan of action is our first priority as we know it is essential in order to properly conduct peripheral activities and manage downtimes.
Mechanical design and reliability
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The mechanical design and engineering rules applied in our design office are based not only on design codes but, above all, on our expertise in reliability and the local behaviour of the heterogeneous structure of brazed equipment.
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We are able to ensure equipment reliability and durable service thanks to our knowledge of local stresses which are a potential source of failure if they are not dealt with.
The sensitive areas of each apparatus, typically the attachment of headers on the matrix, are subjected to pressure loads and thermal gradients. They can be verified using the finite-element analysis software we have developed: PC Diam. It is impossible to model our heterogeneous structures in sufficient detail using conventional software. We therefore developed our own tools to process these complex models, and they are able to efficiently apply the most advanced techniques to all our equipment.
Pipe flexibility
We have integrated the computation of pipe flexibility so that we can always guarantee the reliability of our designs for the various operating modes and transient conditions. Pipes are the interface between our equipment and the rest of the customer’s site. To maximize the synergy of our design for our customers, we selected the most efficient software, which is also used by our customers.
Transient thermomechanical simulation
Transient computations are performed to determine temperature ranges with respect to time during changes in operating conditions. This unusual type of simulation, which is difficult to carry out, is not an end in itself. After a given period of time, the system reaches a steady state which is all we need to know as far as the process is concerned.
The main purpose of this computation, however, is to determine the thermomechanical stresses and their changes with respect to time. This is achieved by taking the temperatures determined by the transient thermohydraulic computation and applying them to the complete mechanical model of the heat exchanger
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The modeller developed within the company (HomPass, Siteme) allows us to conduct studies with descriptions of even the smallest details (fins, clearances, plates, orientations, etc.), so that we can ascertain, with the utmost precision, the behaviour of the body and the phenomena that occur within it, even if they are very short-lived.
In other words, thanks to the tools we have developed, the seemingly impossible dream of a design process completely integrating events related to the changeability of operating conditions has come true.
Mechanical and thermal design
We have a team of engineers specialized in thermohydraulic equipment design based on customers’ requirements. Our areas of priority are:
Heat exchange capacity and thermal performance,
Pressure drops,
Process-fin compatibility,
Safety of the equipment (hazardous substances, chemical reactions, stability, etc.)
Overall dimensions,
Reliability
Another team is specialized in mechanical design in accordance with customer specifications and preliminary thermohydraulic studies, taking into account the following main criteria:
Compliance with codes and standards (ASME, PED, etc.),
Flexibility and thermal contractions,
External loads,
Customer interface,
Instrumentation,
Design conditions (earthquakes, wind, transport, handling),
Installation on site and prefabrication,
And, in all cases, reliability.
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Thermal design
With the help of its partners, NORDON CRYOGENIE develops and validates its own software tools:
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Simulation computations 
