GB2051296A - A pressure hose line - Google Patents

Abstract

The task underlying the invention is to eliminate, in underground pressure hose lines, the necessity of absorbing the internal pressure by means of the appropriate dimensioning of the wall thickness. According to the invention, there is installed underground a pressure hose line wherein the strength of the highly expansible hose material is less than is necessary at the pressure applied, and the high pressure in the hose line is absorbed by the earth. The invention is mainly used in agricultural irrigation plants. A cover plate may be placed between the hose and earth located thereabove. Plants may be provided to increase the resistance of the earth. <IMAGE>

Description

SPECIFICATION A pressure hose line The invention relates to a pressure hose line which is installed underground for the transportation of liquid intended, more especially, for use in irrigation plants employed in cultivated agricultural areas.

It is known to employ metallic, ceramic or highly polymeric materials for pressure pipe lines and to dirnension them in such a way that the optimum strength is secured by a pipe wall thickness that corresponds to the delivery pressure. In connection with irrigation plants, there are mainly installed in the subsoil PVC, asbestos cement or steel pressure pipe lines as well as thick-walled PE pressure hose lines of different nominal widths, pressure stages and profiling. Due to the wall thickness that corresponds to the delivery pressure, the known lines are very expensive in materials and high in cost (LOFFLER, inter alia: Pocket-book of soil improvement - projecting, Berlin, 1978; STRIEN, H., MERTSCHUNG, E. and NOTZOLD, G.: Handbook for pipeline engineering, Berlin 1975).

It is the aim of the invention to reduce the cost and expenditure of material for irrigation plants.

The task underlying the invention is to eliminate, in pressure lines installed underground, the necessity of absorbing the internal pressure by means of appropriate dimensioning of the wall thickness.

According to the invention, a thin-walled hose line of any desired length and nominal width and having a high expansibility is installed underground, the strength of the highly expansible hose material being lower than is necessary for the pressure applied. The high pressure in the hose line is absorbed by the earth, When the hose line is put into operation, it expands up to a pressure compensation cross section; this cross section comes about as the resultant from the expansion pressure of the hose and the counter-pressure produced by the soil which is compressible within limits.

The maximum loadability of the pressure hose line is thus no longer determined by the wall thickness, as is the case in conventional pipe lines, but is determined by the expansibility of the thinwalled hose material in conjunction with the power of resistance of the surrounding soil. The pre-condition is a correspondingly high expansibility of the inpervious hose skin so that the liquid pressure prevailing in the hose can be transmitted to the soil without loss.

The selection of the installation depth and the fineness of the earth or material surrounding the pipe allows the operating pressure to be increased within economically set limits to the values which are necessary for the irrigation operation ( < 1.0 MPa). Furthermore, by putting plants on the filled hose ditch, it is possible to increase the comprehensive strength by the spreading of roots.

If necessary, the pressure hose line can also be additionally protected by a cover plate.

The invention will hereinafter be explained in more detail with reference to an exemplified embodiment.

In the accompanying drawing: FIGURE 1 shows the condition as the hose is placed into the ditch bottom on a 2-3 cm sand bed; FIGURE 2 shows the condition after the surroundings of the hose, which has been precompressed by 0.02 MPa, have been filled up; and FIGURE 3 shows the operating condition after the ditch has been filled up.

As shown in Fig. 1, the hose 1 is placed in its unload slack state on a sand bed 3 which has been put into the ditch 2.

As shown in Fig. 2, the lower portion of the ditch 2 has been filled with the sand 4 for protecting the hose against damage. The hose 1 is pre-loaded.

As shown in Fig. 3, the ditch 2 is filled with earth 5.

The liquid to be transported can be fed into the hose 1 at the intended delivery pressure.

1. A pressure hose line which is illustrated underground for the transportation of liquid intended, more especially, for use in irrigation plants, characterised in that the strength of the highly expansible hose material is less than is necessary at the pressure applied and in that the high pressure in the hose line is absorbed by the earth.

2. A pressure hose line as claimed in Claim 1, characterised in that a cover plate is provided between the sheathing of the hose line and the earth located thereabove.

3. A pressure hose line as claimed in Claim 1, characterised in that planting is effected for the purpose of solidifying the earth above the hose line.

4. A pressure hose line substantially as described with reference to the accompanying drawing.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (4)

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION A pressure hose line The invention relates to a pressure hose line which is installed underground for the transportation of liquid intended, more especially, for use in irrigation plants employed in cultivated agricultural areas. It is known to employ metallic, ceramic or highly polymeric materials for pressure pipe lines and to dirnension them in such a way that the optimum strength is secured by a pipe wall thickness that corresponds to the delivery pressure. In connection with irrigation plants, there are mainly installed in the subsoil PVC, asbestos cement or steel pressure pipe lines as well as thick-walled PE pressure hose lines of different nominal widths, pressure stages and profiling. Due to the wall thickness that corresponds to the delivery pressure, the known lines are very expensive in materials and high in cost (LOFFLER, inter alia: Pocket-book of soil improvement - projecting, Berlin, 1978; STRIEN, H., MERTSCHUNG, E. and NOTZOLD, G.: Handbook for pipeline engineering, Berlin 1975). It is the aim of the invention to reduce the cost and expenditure of material for irrigation plants. The task underlying the invention is to eliminate, in pressure lines installed underground, the necessity of absorbing the internal pressure by means of appropriate dimensioning of the wall thickness. According to the invention, a thin-walled hose line of any desired length and nominal width and having a high expansibility is installed underground, the strength of the highly expansible hose material being lower than is necessary for the pressure applied. The high pressure in the hose line is absorbed by the earth, When the hose line is put into operation, it expands up to a pressure compensation cross section; this cross section comes about as the resultant from the expansion pressure of the hose and the counter-pressure produced by the soil which is compressible within limits. The maximum loadability of the pressure hose line is thus no longer determined by the wall thickness, as is the case in conventional pipe lines, but is determined by the expansibility of the thinwalled hose material in conjunction with the power of resistance of the surrounding soil. The pre-condition is a correspondingly high expansibility of the inpervious hose skin so that the liquid pressure prevailing in the hose can be transmitted to the soil without loss. The selection of the installation depth and the fineness of the earth or material surrounding the pipe allows the operating pressure to be increased within economically set limits to the values which are necessary for the irrigation operation ( < 1.0 MPa). Furthermore, by putting plants on the filled hose ditch, it is possible to increase the comprehensive strength by the spreading of roots. If necessary, the pressure hose line can also be additionally protected by a cover plate. The invention will hereinafter be explained in more detail with reference to an exemplified embodiment. In the accompanying drawing: FIGURE 1 shows the condition as the hose is placed into the ditch bottom on a 2-3 cm sand bed; FIGURE 2 shows the condition after the surroundings of the hose, which has been precompressed by 0.02 MPa, have been filled up; and FIGURE 3 shows the operating condition after the ditch has been filled up. As shown in Fig. 1, the hose 1 is placed in its unload slack state on a sand bed 3 which has been put into the ditch 2. As shown in Fig. 2, the lower portion of the ditch 2 has been filled with the sand 4 for protecting the hose against damage. The hose 1 is pre-loaded. As shown in Fig. 3, the ditch 2 is filled with earth 5. The liquid to be transported can be fed into the hose 1 at the intended delivery pressure. CLAIMS

1. A pressure hose line which is illustrated underground for the transportation of liquid intended, more especially, for use in irrigation plants, characterised in that the strength of the highly expansible hose material is less than is necessary at the pressure applied and in that the high pressure in the hose line is absorbed by the earth.

2. A pressure hose line as claimed in Claim 1, characterised in that a cover plate is provided between the sheathing of the hose line and the earth located thereabove.

3. A pressure hose line as claimed in Claim 1, characterised in that planting is effected for the purpose of solidifying the earth above the hose line.

4. A pressure hose line substantially as described with reference to the accompanying drawing.