Design of an innovative piping system

A new quick-fit joint, a new internal coating to reduce pressure head losses, and the integration with the energy harvester developed in the project have been developed with the objective of reducing costs of installation and maintenance, and reducing costs of pumping and scale deposition and corrosion damage.

Development of an innovative plug-and-play design for pipe installation

To reduce the installation costs and to ease the maintenance of the DHC system in comparison to the existing solutions in the market, a new design of a quick-fit joint has been developed. The quick-fit joint developed in this subtask has been designed to ease the installation and the maintenance of piping networks in DHC systems, eliminating the operation of welding, and reducing costs of equipment needed, time and handwork. Welding is a difficult operation to be done in field, because weather and terrain conditions could affect the quality of the welding cord and the future tightness of the joint.

Standard DHC Preinsulated pipe

Welded ends of preinsulated pipe


The following methodology has been applied to develop de new quick-fit joint:
1) Definition of specifications.
2) Conceptual design.
3) Virtual design.
4) Prototype.
5) Validation of prototype.









Virtual design of physical components of the new joint


Finite Element Analysis (FEA) of the seal design


New joint prototype

The cost and time of installation of this new joint are lower than the existing solutions in the market. Besides that, the design is flexible to be adapted to other pipe sizes, is detachable, and don’t need that the end pipes were flared or grooved. Other advantages are that the number of assembly parts is low, and that it is compatible with the surveillance system based on copper wires. No additional special equipment is needed to install the joint in field, unlike the welded joint.

Development of an internal pipe coating to reduce pressure head losses

To reduce pressure head losses is a critical point for the efficiency of heating systems, related with the electrical consumption of pumps. For that purpose, CEMITEC has worked on the development of a new coating on the inner part of the pipes to reduce roughness and friction coefficient of the surface pipes, something that will allow reducing head losses in order to achieve a more efficient heating system.

The pipe’s surface roughness definitely affects the head losses but also the deposition of scale, lime and other sediments present in the circulating water, which could increase the electricity consumption of pumps in the short (roughness), and in the medium and long term (deposition of sediments).

Pipe with scale deposits

The selected approach to get a functional coating to reduce head losses in pipes has been the additivation of a matrix of already formulated paint with antiadherent additives.

Contact angle, surface energy measurements and adhesion tests were used to screen the best formulation. It has been found that the additivation of a polymeric paint with a silicone additive has resulted in a more antiadherent coating that could reduce in the long term the deposition of lime inside the pipes. The best formulations have been validated according to the standards.

Coated samples






Coated samples after the accelerated scale deposition (left) and after the adherence test (right)


These new coating presents a higher contact angle and a lower surface energy than the unadditivated coating allowing to reduce the deposition of scale, lime and other sediments in the pipes. The reduction on the scale deposition together with the corrosion protection provided by the coating will permit a reduction on the head losses in the medium-long term.

Integration of piping technologies

The objective was integrating the technologies related to piping design and developed during the project, and the energy harvesting system developed by CEA-LETI. The integration will allow installing any sensor connected to the energy harvester and being easily mounted in the network.


Virtual design for the integration of the quick-fit joint and the energy harvester

The integration was successfully, and consisted in the assembly of the new quick-fit joint and the energy harvester with the objective of testing the correct adjustment between parts and the process of mounting, in order to make a good integration of both developments and to test it in the test bench developed for validation. This integration could be used to connect DHC sensors that are compatible with energy harvester output.

Assembly of new quick-fit joint, energy harvester and surveillance system wires


Final integrated piping

New developments of piping technology have been presented, which give new valuable functionalities to the preinsulated pipe used in DHC systems: reducing costs and time of installation with the new quick-fit joint, saving pump electrical consumptions with the reduction of pressure head losses and reducing pipe corrosion thanks to the new coating, and having the possibility of connecting sensors in remote mode thanks to the integration with the energy harvester developed by CEA-LETI in INDEAL project.