DE29815001U1 - Insulated pipes - Google Patents

Description

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ReEnergy 29 May 1998

Energy systems

Thermally insulated pipes

DESCRIPTION

The invention relates to thermally insulated pipes, in particular for transporting the working fluid of thermal solar systems.

Thermal solar systems, especially for the provision of hot domestic water, are becoming increasingly popular. The fact that they are not more widely used is due not least to the complex and therefore expensive installation of the solar collectors.

The invention is based on the task of reducing the costs for installation and operation of thermal solar systems.

The task is solved by providing at least one flow pipe and one return pipe, which have pre-assembled thermal insulation and a pre-assembled covering that surrounds both thermally insulated pipes. The covering turns the pipes, which are pre-insulated at the factory, into a pre-assembled, ready-to-install unit that has no thermal bridges and is easy to install. The mechanical application of thermal insulation and covering achieves high quality and durability.

If the pipes are manufactured at the factory as straight copper pipes, which can be bent together with the thermal insulation and the sheath, there is no need to piece the pipes together from angle pieces

29 May 1998

and connecting sleeves and other components. This shortens assembly time and saves installation material. By eliminating most of the solder joints, the risk of late damage caused by corrosion is reduced. In addition, flow turbulence is reduced, and with it flow and heat losses.

It is advantageous that a plastic film, preferably made of polyethylene, is used as the covering, which is preferably wound up in a spiral or pulled up as a plastic tube and welded to the thermal insulation. The plastic film gives the pre-assembled unit a high level of strength without reducing its flexibility. In addition, the dimensions of the pipe assembly remain within modest limits.

It is also advantageous if the pipes have separate or shared thermal insulation. Separate thermal insulation means greater variation when assembling the pipe pairs, while shared thermal insulation provides maximum strength and the smallest possible dimensions of the pipe connection.

band. _v

If each of the two pipes has a different insulation thickness, it can be designed according to the temperature of the working fluid flowing in the respective pipe. This leads to space and cost savings.

An advantageous development of the invention is that at least one of the two pipes has a continuous marking. This can, for example, consist of a color marking on the outside or inside of the pipe, or a thread attached to the outside of the pipe. It serves to reliably distinguish between forward and return flow.

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29 May 1998

It is advantageous that both pipes have the same cross-section, but can be made in different dimensions. In this way, thermal solar systems of different sizes can be installed and the optimal flow cross-section can be selected in each case.

Of course, the required flow cross-section can also be achieved by connecting several ready-to-install units in parallel. Each of the parallel units can have a flow and a return. However, it is also conceivable that one unit with its two pipes is used as the flow and the parallel unit as the return.

Because the insulating material is preferably temperature-resistant up to +175°C and is PVC and CFC-free, high idle temperatures of the working fluid are also permissible. In addition, the ecological requirements for the raw material are taken into account.

It is also advantageous that at least one two-wire cable is provided within the casing. This provides a cable for the temperature sensor on the collector and, if required, additional cables for measuring or control functions.

The fact that waterproof connectors can be mounted at the ends of the two-wire cable makes electrical installation easy.

Further features of the invention emerge from the claims, the following description and the drawing, in which embodiments of the invention are shown schematically.

-A-

29 May 1998

Show it:

Figure 1: a cross-section through a thermally insulated pipe bundle,

Figure 2: a longitudinal section through a thermally insulated pipe bundle with subsequently bent pipes.

Figure 1 shows a flow pipe 1 and a return pipe 2, both of which are surrounded by thermal insulation 3. This is applied separately to both pipes 1, 2 at the factory and covered by a UV-resistant cover 4 in the form of a plastic film made of polyethylene. Under the cover 4 there are two two-core cables 5, at the ends of which waterproof plugs (not shown) can be mounted. Together, the pipes 1, 2 with their thermal insulation 3, the two two-core cables 5 and the cover 4 form a pre-assembled unit 6.

In Figure 2, the two pipes 1, 2 are shown in a bent state and with a common thermal insulation 3. The flow-optimized routing of the pipes 1, 2 is evident. Also the absence of any fittings and soldering points and the lack of thermal bridges.

The preassembled unit 6 according to the invention is simple and inexpensive to process and assemble and, due to its low heat and flow losses, is also inexpensive to operate.

Claims (10)

29 May 1998 Thermally insulated pipes CLAIMS 1. Thermally insulated pipes, in particular for transporting the working fluid of thermal solar systems, characterized in that at least one flow pipe (1) and one return pipe (2) are provided, which have a pre-assembled thermal insulation (3) and a likewise pre-assembled covering (4) enclosing both thermally insulated pipes (1, 2). 2. Thermally insulated pipes according to claim 1, characterized in that the tubes (1, 2) are designed at the factory as straight copper tubes which are bendable together with the thermal insulation (3) and the covering (4). 3. Thermally insulated pipes according to claim 1 or 2, characterized in that a plastic film, preferably made of polyethylene, is provided as the covering (4), which is preferably wound spirally or pulled up as a plastic tube and welded to the thermal insulation (3). 4. Thermally insulated pipes according to one or more of the preceding claims, characterized in that the pipes (1, 2) have separate or common thermal insulation (3). ·· -6- 29 May 1998 5. Thermally insulated pipes according to one or more of the preceding claims, characterized in that each of the two tubes (1, 2) has a different insulation thickness.
5 6. Thermally insulated pipes according to one or more of the preceding claims, characterized in that at least one of the two tubes (1, 2) has a continuous marking.
10 7. Thermally insulated pipes according to one or more of the preceding claims, characterized in that both tubes (1, 2) have the same cross-section, but can be made in different dimensions. 8. Thermally insulated pipes according to one or more of the preceding claims, characterized in that the insulating material is preferably temperature-resistant up to +175 ⁰ C and is PVC- and CFC-free. 9. Thermally insulated pipes according to one or more of the preceding claims, characterized in that at least one two-core cable (5) is provided within the casing (4). 10. Thermally insulated pipes according to claim 9, characterized in that waterproof plugs can be mounted at the ends of the two-core cable (5).