Fire extinguishing system

Abstract

A fire extinguishing system including a fluid source, at least one sprinkler (2), and distribution pipes (3). The distribution pipes (3) are formed at least partially as soft-steel metal pipe having a friction loss defined according to the Hazen-Williams formula (1), with P=6.05.Math.10.sup.5.Math.L.Math.Q.sup.1.85.Math.C.sup.(−1.85).Math.d.sup.(−4.87), in which P=pressure drop in the pipeline, in bar, Q=flow rate through the pipeline, in l/min, d=average inside diameter of the pipe, in mm, C=constant for the type and condition of the pipeline, and L=equivalent length of pipe sections and pipe fittings, in m. The distribution pipes (3) have an anti-corrosion coating on the inside in order to ensure a value for C in a range of 125 to 150 during commissioning of the fire extinguishing system.

Claims

1. A mild steel metal pipe for a fire extinguishing system for distributing an extinguishing medium, the extinguishing system at least having means for providing the extinguishing medium, at least one means for applying the extinguishing medium, transport means for connecting the means for providing the extinguishing medium to the at least one means for applying the extinguishing medium, wherein the transport means are at least partially in the form of a plurality of the mild steel metal pipes, and wherein the pipe friction loss in each of the mild steel pipe of the plurality of mild steel pipes is defined in accordance with the Hazen-Williams formula with
P=6.05.Math.10.sup.5.Math.L.Math.Q.sup.1.85.Math.C.sup.(−1.85).Math.d.sup.(−4.87) wherein: P=pressure drop in the pipe, in bars, Q=through-flow rate through the pipe, in 1/min, d=mean inside diameter of the pipe, in mm, C=constant for type and condition of the pipe, and L=equivalent length of pipe and shaped portions, in m, the mild steel pipe comprising: an at least inwardly disposed corrosion protection coating, the inwardly disposed coating comprises a non-porous polymer layer containing iron and epoxy-acrylic, the non-porous layer being ionically bonded to at least an inner surface of the mild steel metal pipes and having a thickness greater than 15 μm to provide a value for C in a range greater than 120 to 150 when the fire extinguishing system is commissioned for use and has a nominal width in a range of DN 32 to DN 250.

2. The mild steel metal pipe for a fire extinguishing system according to claim 1, wherein the inwardly disposed corrosion protection coating provides a value for C in a range of 125 to 150.

3. The mild steel metal pipe for a fire extinguishing system according to claim 1, wherein the inwardly disposed corrosion protection coating is adapted to ensure a value for C in a range of 135 to 150 upon commissioning of the fire extinguishing system.

4. The mild steel metal pipe for a fire extinguishing system according to claim 1, wherein the inwardly disposed corrosion protection coating provides a value for C in a range of 135 to 150, and wherein the thickness greater than 15 μm comprises a thickness in the range of 15-28 μm.

5. The mild steel metal pipe for a fire extinguishing system according to claim 1, wherein the mild steel metal pipe for forming the transport means is of a nominal width in a range of DN 32 to DN 250.

6. The mild steel metal pipe for a fire extinguishing system according to claim 2, wherein the mild steel metal pipe for forming the transport means is of a nominal width in a range of DN 32 to DN 65.

7. The mild steel metal pipe for a fire extinguishing system according to claim 5, wherein the mild steel metal pipe comprises a wall thickness in a range of 2.0 mm to 2.5 mm.

8. The mild steel metal pipe for a fire extinguishing system according to claim 1, wherein the extinguishing medium is a medium selected from the list including: water, foam, water-foam mixture, gas, chemical extinguishing agents.

9. A corrosion resistant pipe for a fire extinguishing system that distributes an extinguishing medium, the system comprising a plurality of the corrosion resistant pipes, each corrosion resistant pipe, comprising: a mild steel pipe including a non-porous layer ionically bonded to at least an interior surface of the mild steel pipe, the non-porous layer containing iron and epoxy-acrylic and having a thickness of at least 15 μm to provide a C value in a range greater than 120 to 150 when used in the fire extinguishing system, and has a nominal width in a range of DN 32 to DN 250.

10. The corrosion resistant pipe for a fire extinguishing system of claim 9, wherein the non-porous layer containing iron and epoxy-acrylic is ionically bonded to an exterior surface of the mild steel pipe.

11. The corrosion resistant pipe for a fire extinguishing system of claim 9, wherein the nominal width in a range of DN 32 to DN 250 comprises a nominal width in a range of DN 32 to DN 65.

12. The corrosion resistant pipe for a fire extinguishing system of claim 11, wherein the mild steel pipe comprises a wall thickness in a range of 2.0 mm to 2.5 mm.

13. The corrosion resistant pipe for a fire extinguishing system of claim 11, wherein the non-porous layer containing iron and epoxy-acrylic is ionically bonded to an exterior surface of the mild steel pipe.

14. The corrosion resistant pipe for a fire extinguishing system of claim 9, wherein the thickness of the non-porous layer of at least 15 μm comprises a thickness in the range of 21-27 μm.

Description

DRAWINGS

(1) The FIGURE hereinafter is intended to describe the invention more fully.

(2) The FIGURE shows the structure in principle of an installation implemented for test purposes and to verify the invention made, that is in the form of a dry sprinkler installation with periodically implemented sprinkler inserts.

DETAILED DESCRIPTION

(3) A branched system of transport means (3) is connected to a means (1) (only diagrammatically indicated) for providing the extinguishing medium, here water, in the form of a single water supply, wherein the transport means (3) include a central riser conduit [(3), a] a plurality of distributor conduits [(3), b] branching from the central riser conduit [(3), a], and for each distributor conduit [(3), b] a respective plurality of branches or branch conduits [(3), c]. In that respect for the sake of simplicity of the drawing, the FIGURE completely shows only one distributor conduit [(3), b] and in relation thereto only a few branches [(3), c].

(4) Each branch [(3), c] has at its beginning directed to the distributor conduit [(3), b] and at its end a respective ball valve (5), upstream of the ball valve (5) at the end of the branch [(3), c] a manometer (6), three respective sprinklers as means (2) for applying the extinguishing medium, and a plurality of coupling connections (4) for possible individual replacement of each sprinkler (2).

(5) In total fitted in the test installation there are thus a total of 60 branches [(3), c] of a respective nominal width of DM 32 and of a respective wall thickness of 2.6 mm, five branches [(3), c] of mild steel metal pipes with an epoxy/acrylic-based inwardly disposed corrosion protection coating. In that arrangement that inwardly disposed corrosion protection coating in all of those five branches [(3), c] is of a thickness in a range of 15 to 27 in the branches [(3), c] of the particularly preferred variant the thickness is in a narrower range of 21 to 27 μm. In all of those five branches [(3), c] the epoxy/acrylic-based inwardly disposed corrosion protection coating is produced by means of the Aquence™ method of the 900 series. A further 49 branches [(3), c] of the test installation are constructed with galvanized mild steel metal pipes, the remaining six branches [(3), c] have mild steel metal pipes without any internal coating.

(6) After a 12 month test time with constantly changing operating conditions and severe outside climate fluctuations from moist-warm through dry-hot to dry-cold and wet-cold the branches [(3), c] of mild steel metal pipes with the epoxy/acrylic-based inwardly disposed corrosion protection coating exhibit scarcely any corrosion at the respective branch ends while surface corrosion cannot be detected at all. All threads on the respective coupling connections (4) after the end of the test time are also still completely sealed and exhibit in principle no corrosion attacks. In contrast both the galvanized mild steel metal pipes and also the mild steel metal pipes without any internal coating at the branch ends and towards the coupling connections (4) have a marked rusting attack in the pipe interior, even if slight but clearly detectable, which leads to a marked reduction in the C-values. Only the mild steel metal pipes with the epoxy/acrylic-based inwardly disposed corrosion coating have a value for C of 140 at the end of the 12-month test period, which exactly corresponds to the value at the beginning of the long-term test.

(7) Thus the realizations deriving from operation of the test installation show on the one hand the great advantages of a fire extinguishing system according to the invention over previous fire extinguishing systems, while on the other hand they also show that, by means of the fire extinguishing system according to the invention, the underlying problems of the invention for achieving a monetary improvement in the design and operation of sprinkler installations can be lastingly solved.

LIST OF REFERENCES

(8) (1) means for providing the extinguishing medium (2) means for applying the extinguishing medium (3 transport means (3), a—riser conduit (3), b—distributor conduit (3), c—branch (conduit) (4) coupling connection (5) ball valve (6) manometer