JPH0243072B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to improvements in fluid transport pipes for transporting fluids such as crude oil or natural gas and various chemicals extracted from oil or gas wells.

Generally, fluid transport pipes of this type consist of a plastic pipe, a metal reinforcing layer provided on the outside of the plastic pipe, and a plastic jacket provided on the metal reinforcing layer. but,
When crude oil and natural gas are sent through this fluid transport pipe,
The corrosive gas contained therein may permeate the plastic pipe in the radial direction and accumulate inside the plastic sheath, adversely affecting the metal reinforcing layer or damaging the plastic pipe and the plastic sheath. It was hot.

SUMMARY OF THE INVENTION The object of the present invention is to provide a fluid transport pipe in which the above-mentioned disadvantages can be avoided in that the gases that have passed through the plastic pipe do not accumulate inside the plastic jacket.

Embodiments of the present invention will be described with reference to the drawings. The drawings show a fluid transport pipe 10 according to the invention, which comprises a plastic pipe 12 and a metal reinforcing layer 1 provided on the outside of the plastic pipe 12.
4 and a plastic jacket 16 provided on the outside of this metal reinforcing layer 14. In the illustrated embodiment, the metal reinforcing layer 14 includes an internal pressure reinforcing layer 18 that protects the plastic pipe 12 from the internal pressure of the fluid by wrapping a metal tape in multiple layers spirally around the outside of the plastic pipe 12, and an internal pressure reinforcing layer 18 that protects the plastic pipe 12 from the internal pressure of the fluid. Armor 2 that protects from external water pressure etc. by twisting steel wires together.
It consists of 0. In the illustrated embodiment, the plastic pipe 12 has an internal reinforcing layer 22 made of a flexible metal tube and a plastic inner sheath 24 provided inside the internal reinforcing layer 22, but these are omitted. Good too.

The fluid transport tube 10 of the present invention has an outer plastic jacket 16 that has a greater gas permeability than the inner plastic pipe 12. This gas permeability is determined by the materials of the plastic pipe 12 and the plastic sheath 16. For example, plastic pipe 12 is typically formed from nylon, while plastic jacket 16 is formed from silicone rubber, which is more gas permeable than nylon.
Note that the plastic inner jacket 24 is made from the same nylon as the plastic pipe 12.

As described above, since the outer plastic sheath 16 is made of a material with higher gas permeability than the inner plastic pipe 12 and plastic inner sheath 24, corrosive gases that permeate through the plastic inner sheath 24 and plastic pipe 12 are prevented. When the gas reaches the plastic jacket 16, it does not accumulate inside the plastic jacket 16 and the plastic jacket 1
6 and escapes to the outside, so the fluid transport pipe 10
No damage to the components. In addition, since the plastic jacket does not have ventilation holes, water or moisture cannot enter from the outside through these ventilation holes, and therefore the metal reinforcing layer will not be corroded by the external atmosphere and fluid transport. The life of the tube can be extended.

According to the present invention, as described above, the plastic sheath is made of a material with greater gas permeability than the plastic pipe, so that the gas that has permeated through the plastic pipe does not accumulate inside the plastic sheath. It does not damage metal reinforcing layers, plastic pipes, or outer coverings, and is particularly suitable for transporting crude oil and natural gas. In addition, since the plastic jacket does not have ventilation holes, water or moisture cannot enter from the outside through these ventilation holes, and therefore the metal reinforcing layer will not be corroded by the external atmosphere and fluid transport. The life of the tube can be extended.

[Brief explanation of the drawing]

The drawing is a cross-sectional view of a fluid transport pipe according to the present invention. 10...Fluid transport pipe, 12...Plastic pipe, 14...Metal reinforcement layer, 16...Plastic jacket.

Claims (1)

[Claims] 1. A fluid transport pipe comprising a plastic pipe, a metal reinforcing layer provided on the outside of the plastic pipe, and a plastic sheath provided on the outside of the metal reinforcing layer, wherein the plastic sheath has a larger gas capacity than the plastic pipe. A fluid transport pipe characterized in that it is made of a permeable material.