Thermoplastic pipes ready for winter: tips for safety and efficiency

Winter can be a significant challenge for construction and plumbing projects, as the drastic drop in temperatures can cause pipes freezing and, as a result, delays in execution or costly project disruptions. However, by taking advantage of knowledge about material responses to application temperatures, it is possible to execute installations within the timeframe imposed by the construction site.

Winter’s challenge: polypropylene pipes and low temperatures

With the cold season, building professionals are often faced with a recurring dilemma: the negative impact of cold temperatures on their installations.

When temperatures fall below certain thresholds, building materials become increasingly difficult to work with.

There is a false myth that plastic pipes cannot be installed and processed in cold conditions. On the contrary, plastics are suitable for handling temperature variations. Aquatechnik PP-R pipes are designed to be reliably installed even in outdoor temperatures as low as -5 degrees. This keeps winter construction sites operational, prevents delays and avoids additional costs.

Essential tips for working with pipes in winter

Let’s look at five essential tips for safe and efficient processing of synthetic pipes in winter conditions.

1. Choosing the right material

The first step to ensure the success of winter pipe processing is the choice of the appropriate material. Our PP-R piping systems are specifically designed to withstand the challenges of low-temperature construction. Thanks to their ability to work efficiently at temperatures as low as -5°C degrees, Aquatechnik’s polypropylene pipes are a viable solution, even in winter projects.

Aquatechnik’s fiber-reinforced single and multilayer pipes are also ideal for applications with chilled water, mixed with glycol, at temperatures as low as -20°C.

Other options include the choice of Aquatechnik multilayer pipes. The top of the range of multilayer pipes, the Multi-calor pipes, work down to temperatures as low as -45°C and are characterized by a high flexibility, conferred by the five layers joined together. The PE-Xb cross-linked polyethylene outer layer, mechanically, electrically, and chemically protects the aluminum layer, which ensures total impermeability to oxygen and light, as well as providing flexibility in laying. The reduced value of the coefficient of linear thermal expansion allows a significant reduction in the axial elongation of the pipes compared to those made of other thermoplastic materials.

2. Temperature management and material preparation

Temperature management is crucial when working with polymer pipes during winter.

In order to ensure a successful installation, it is essential that both pipes and connecting fittings have the same temperature levels: in fact, temperature variations can cause problems with joints and compromise the stability of the welds. We recommend always following the manufacturer’s guidelines for temperature control and efficient installation.

The polyfusion process of the Fusio-technik system requires the polyfuser to operate at the correct temperature. 

The correct processing times for temperatures below 5°C are indicated in the dedicated catalogue. Before starting the welding process, it is essential to ensure that all components are completely free of ice and moisture.

This requirement applies to both pipes and fittings.

Since these factors can have a significant impact on the quality of the joint, it is essential to take the time to carefully remove any residue before starting processing.

To ensure that everything works properly, it is advisable to perform test welds to check that the processing conditions are optimal and that the joints meet the requirements. In case of heat-sealable materials, the longer processing time is dictated by the greater effort the polyfuser and matrixes take to reach the correct operating temperature.

Regarding multilayer piping with the Safety system, machining depends on the performance variations that the flaring machine tool might experience at low temperatures. In fact, like all battery-powered  mechanical tools, their use in adverse environmental conditions can affect battery life and mechanical machine cycle times.

3. Consider linear expansion

Thermoplastic materials are more susceptible to linear thermal expansion than metallic materials, but this phenomenon is much more significant at high temperatures. In order to limit the linear thermal expansion value of PP-R pipes, Aquatechnik has in recent years developed a series of multilayer pipes with a glass fiber-filled middle layer: these special pipes reduce the thermal expansion value by 70% compared to single-layer pipes (α=mm/mk 0.035 versus 0.150 of homogeneous PP-R pipes).

Multi-calor pipes, with their aluminium inner layer, act similarly, with the linear thermal expansion coefficient α=mm/mk of the multilayer being 0.026. 

For both systems and for a good design, it is essential to consider the pipe clamping distances considering the difference between fluid and installation temperature.

4. Protection of the material

At low temperatures, the impact resistance of polymer pipes may decrease. It is essential to handle the material with care to safeguard both pipes and fittings from mechanical stresses such as impacts or falls. Treating the material with care, especially in cold conditions, helps prevent damage and potential weaknesses in construction.

5. Insulating pipes: Aquatechnik solutions

Preventing pipes from freezing starts with careful placement. Placing pipes inside the home, when possible, allows them to benefit from indoor heating and insulation.

Insulation is a key element in preventing pipe freezing problems. Pipes can freeze when exposed to low temperatures, but proper insulation can help reduce this risk, as well as improve the energy efficiency of the heating system.

Insulation is particularly effective for central heating pipes or with sources and boilers far away from the user.

The Iso-technik system is the most efficient solution for installations in adverse climatic conditions. A complete range of single pipe and pre-insulated fittings with PUR foam (rigid polyurethane) protected by PE-HD casing pipe, combining the high performance of PP-RCT WOR (White Oxidation Resistance) service pipe with energy-saving insulation.

Iso-technik is used for remote energy distribution, either in direct or indirect form, via water carrier fluid and includes pipes and fittings with diameters in a range from 32 mm to 315 mm, available in the following versions: Iso FIBER-T SDR 7.4, for high-temperature plumbing systems; Iso FIBER-COND SDR 11, for medium-temperature plumbing systems and high-temperature heating systems; Iso FIBER-LIGHT SDR 17.6 for low-temperature plumbing systems and heating systems at medium temperatures and pressures.

Among Iso-technik’s advantages is the ease of laying, resulting both from the low weight of polypropylene piping compared with other materials, and from the possibility of assembly of the line out of the trench and relocation in the excavation afterwards.

Also Aquatechnik’s multilayer pipes are available in a pre-insulated version. Multi-calor Isoline, with a green heat-insulating sheath, is the line dedicated to high-temperature heating and plumbing systems that is characterized by energy efficiency, while the version with a blue heat-insulating sheath is also anti-condensation.

Multi-calor Isoline-plus, with blue or red thermal insulation sheathing, has an increased insulation value of λ 0.035.

 

Excellence for pipe system installations, even in winter

Multilayer and PP-R fittings and pipes find a wide range of applications even at low temperatures. They are a staple  in cold-water plumbing systems due to their resistance to low temperatures, which ensures reliable performance and prevents pipe failures caused by freezing.

Furthermore, Aquatechnik systems can be used in heating, ventilation and air conditioning systems operating in cold conditions. By ensuring proper insulation and routine maintenance, these systems can operate efficiently even in extremely cold conditions.

In addition to domestic use, polymer pipes and fittings are also used in industrial applications requiring low temperatures, such as food processing, refrigeration and cryogenic storage. Their ability to withstand cold makes them suitable for the stringent requirements of these sectors, further highlighting their versatility.

Correct installation and regular maintenance, together with quality piping and fittings, make the difference for optimal performance in cold environments.

Safety and performance are guaranteed, exploiting the potential of Aquatechnik systems 365 days a year.