BARTEC Ensures Right Temperatures at EPC-2 Island Kashagan
Eric Specht, Project Manager Heating Technology, BARTEC S.r.l.

BARTEC has been awarded for the engineering, procurement and construction management of heat tracing on EPC-2 island of Kashagan project. For keeping the plant operating under the worst conditions, the target is to maintain a strategic pipe network. The case study details the advantages of the used parallel heating cables, PSB and HSB, the self-limiting property of which prevents overheating even when the cables are overlapped, and much more.

Kashagan, 80 km south-east of Atyrau in the North Caspian Sea, is the largest oil field discovered over the last thirty years world-wide and extends over a surface area of approximately 75 km by 45 km. Its development represents one of the greatest challenges faced by the petroleum industry, given the deep, high-pressure reservoir, the high sulphur content, the shallow waters that freeze in winter and the marked shifts in temperature (from -36C to +43C). The potential daily average production amounts to 1.2 million barrels, with estimated reserves of 38 billion barrels.

Due to the previous successful realisation of different offshore applications, BARTEC has been awarded for the engineering, procurement and construction management of heat tracing on EPC-2 island of Kashagan project. The target is to maintain a strategic pipe network, in order to keep the plant operating under the worst conditions. Heat tracing was also used for the freeze protection of the helideck.

The used cable was the self-limiting parallel heating cable PSB as well as the self-limiting parallel heating cable HSB. The convincing advantage of these two kinds of cables is their ability to be used in explosive atmospheres without any temperature limiter. Consequently, costs for further components could be saved. More than 10,000 m are installed.

Both cables have a CTP resistive element between two parallel copper conductors which regulates and limits the heat output of the heating cable according to the ambient temperature. This output regulation is carried out automatically along the entire length of the heating cable according to the prevailing ambient temperature. As the pipe temperature rises, the heat output of the cable is reduced. This selflimiting property prevents overheating even when the cables are overlapped. A temperature limiter is not required, not even in explosion hazardous zones as on EPC-2 Island. Thanks to the parallel power supply the heating cable can be cut to any required length. This feature considerably simplifies project planning and installation. The heating cable is cut and terminated in accordance with the local requirements directly on the construction site. The protective outer jacket of either fluor polymer protects the inner copper braiding from corrosion and chemical attack. The copper braiding serves as earth conductor and also increases the mechanical stability of the cable. Under the protective braiding are two synthetic jackets providing electrical insulation. The inner of the two jackets is thermally fused to the heating element (bonded jacket).

The system provider BARTEC did not only provide the heating cables and the connection kits but also the control technology required to offer a complete solution from one hand. The used DPC temperature controller was implemented in combination with Pt100 sensors. It is particularly suitable for pipe sensing and ambient sensing. Whenever the set temperature value at the sensor is exceed or fallen below, the output relay will automatically switch on or off. BARTEC can also configure as SRAP, which consist to calculate the necessary power in function of the ambient temperature. The available power is calculated taking into account the worst case, the instantaneous power id depending on the instantaneous ambient temperature. The necessary power under -36C ambient is not the same under -10C ambient, for a winterising this power would be less than the half. The client can also appreciate that the regulating system, modulate the power in order to avoid overheating and reduce the energy costs of heat tracing.

In order to ensure a reliable design, the engineering has been per formed by working with the 3D model. By working in 3D, BARTEC was able to "see" the plant before it has been built. The location of junction boxes could be defined taking into account the future preventive maintenance and any inspection of the system which use to occur on a yearly base.

Further from the engineering and the supply of the heating technology products, BARTEC also provided skilled personal in order to assist with the installation, to exchange knowledge, and to save clients time so that they can dedicate about their activity, letting BARTEC care about the heat tracing and coordination with other sub-contractors like thermal insulation and power distribution.

Prior to enter EPC-2 Island, a specific training was mandatory for the BARTEC specialists, the Basic Off-Shore Safety Induction and Emergency Training (BOSIET). This intensive three-day experience included the training how to proceed with different dangerous types of incidents which can occur during offshore activities. After the successful completion of this training , they now have the permission to work on any offshore plant worldwide.

By competently handling this project, BARTEC succeeded in laying the foundations for further cooperation. The safety technology provider has once again proven its competence to meet the requirements on a variety of markets worldwide.