ARRANGEMENT FOR PREVENTION OF FREEZING OF WATER PIPELINES IN A FIRE FIGHTING PLATFORM EQUIPPED WITH TELESCOPIC BEAMS

Abstract: The object of the invention is a system intended for preventing the freezing of fire extinction water piping (20) in an elevating platform equipment provided with a telescopic elevating boom system (12). The fire extinction water piping extends from the vehicle level to a hydraulic gun (22) arranged in connection with a working cage (15) and comprises a telescopic water piping section (25) running along the elevating boom system (12) as well as piping sections (28, 23, and 24, 27, 29) located on both sides of the telescopic water piping section. The invention is characterised in that the system comprises a circulating water line (30) provided with a circulation pump (35) arranged in parallel with the water piping (20), whereby the ends (31, 32) of the circulating water line are intended to be connected to the water piping (20) on both sides of its telescopic water piping section (25). The invention also relates to a fire extinction water piping and to an elevating platform equipment equipped with said system.

Description: ARRANGEMENT FOR PREVENTION OF FREEZING OF WATER PIPELINES IN A FIRE FIGHTING PLATFORM EQUIPPED WITH TELESCOPIC BEAMS The object of the invention is a system intended for preventing the freezing of fire extinction water piping in an elevating platform equipment provided with a telescopic elevating boom system and intended for fire-fighting use. The invention also relates to a fire extinction water piping and to an elevating platform equipment equipped with said system. The fire extinction water piping of an elevating platform equipment provided with a telescopic elevating boom system and intended for fire-fighting comprises mainly a water piping section running along the elevating boom system, and pressure hoses located at the articulated joints. The outermost telescopic water pipe is isolated and generally provided with a lining heater operated by electric resistance. When the elevating platform is elevated and the telescopic pipes of the water piping are pulled out there is a great risk of their freezing in extreme cold weather when the flow of fire extinction water is shut off, but the elevating platform is still in an elevated position, e.g. for post-clearance works. The inner pipes of the telescopic piping are of steel and they can not be equipped with heaters, neither with thermal insulation, as this would impose an obstacle to their telescopic motion. As a result of the freezing of the water piping a continued fire-fighting is prevented. Further, the lowering of the elevating platform and the retraction of the elevating boom system is prevented if the water piping is frozen. The object of this invention is to eliminate the above presented problem and to provide a system which prevents the freezing of the fire extinction water piping, even in extremely low temperatures. The characteristics of the invention are disclosed in the independent claims. The fire extinction water piping according to the invention is characterised in that a circulating water line provided with a circulation pump is arranged in parallel with the water piping, the ends of the c culating water line being connected to the water piping on both sides of its telescopic water piping section. The invention is described below with reference to the enclosed drawing, which shows an elevating platform equipment intended for fire-fighting in its transport position. The equipment is intended to be arranged in a vehicle (not shown in the figure). The equipment comprises a turntable 11 supported on a vehicle, a support frame 10, a telescopic elevating boom system 12, swinging booms 14, 16, and a working cage 15. Within the outermost pipe or the basic boom 12a of the elevating boom system, there are extension booms 12b to 12d arranged within each other. The elevating cylinder is denoted by the reference numeral 13. Further, the equipment comprises a fire extinction water piping 20, the first end 21 of which extends from the vehicle level and which is ends in a hydraulic gun 22 arranged in connection with the working cage 15. The water supply up to the hydraulic gun 22 is made for instance from another fire-fighting unit, from the water network, or from a fire ex- tinction pump mounted in the elevating platform vehicle. The piping 20 contains a number of components, in other words: a steel pipe 28 passing through the turntable 11; pressure hoses 23, 24 and 27 which are located at the articulated joints 17 and 18 and at the swinging boom 16 of the working cage 15; a steel pipe 29 running along the swinging boom 14; and a water piping section 25, which also is telescopic and runs along the telescopic elevating boom system 12, and in which there are pipes 25b to 25d arranged within each other within the outermost pipe 25a. The telescopic piping section 25 is of steel. The outermost pipe 25a of the water piping section 25 is enclosed by a heater 26 provided with an electric resistance. However, the telescopic pipes 25b to 25 d can not be equipped with heaters, and therefore freezing may easily occur in them when they are pulled out and it is extremely cold. According to this invention a circulating water line 30 provided with a circulation pump 35 is arranged in parallel with the water piping 20, the ends 31, 32 of the circulating water line being connected to the water piping 20 on both sides of its telescopic water piping section 25. The circulating water line 30 is provided with a heater 33, which suitably is an electrical resistance. In the figure, the circulating water line 30 is presented as running on the outside of the elevating boom system 12 but according to a preferred embodiment, the circulating water line 30, being a flexible pressure hose, is arranged together with electrical cables and corresponding equipment to run along a cable rack (not shown in the fig- ure) within or on the outside of the elevating boom system 12. Here the circulating water line is well protected, for instance against the freezing effect of wind. The circulating water can be conveyed in the direction shown by the pump 35, or in the opposite direction. The purpose of the circulating water line 30 is to protect the telescopic water piping section 25 from freezing, and therefore the line 30 must be con- nected to the water piping 20 so that the connection point of its first end 31 is located somewhere below the telescopic water piping section 25 and that the connection point of the other end 32 is located somewhere above the water piping section 25. Thus, the connection points marked in the figure are only exemplary. An alternative connection point of the end 31 could be for instance at the feeding point of the pressure hose section 23. Alternative connection points of the end 32 could be for instance just in front of the valve of the hydraulic gun 22 , or just before the pressure hose 24 (in other words after the innermost telescopic pipe 25d). The connection point shown in the figure is recommendable in that also the pressure hose section 24 and the water pipe 29 of steel ranning along the swinging boom 14 get a protection against freezing. It would be even more recommendable to locate the connection point just in front of the valve of the hydraulic gun, because then the whole water line would be protected against freezing thanks to the circulating water line. Suitably the circulating water line is thermally insulated. The heater 33 can be a locally acting heater according to the figure, or an electrical resistance rurming along the whole line or along a substantial part of it. The heating system according to the invention effectively prevents freezing of the extinction water piping even in an extremely cold temperature (-30 to -35 °C). The heating system can be used in all positions of the telescope. The above mentioned embodiments of the invention are only examples of how the inventive idea can be realised. To a person skilled in the art it is obvious that differ- ent embodiments of the invention can vary within the claims presented below.

Claims: Claims 1. A fire extinction water piping (20) in an elevating platform equipment provided with a telescopic elevating boom system (12) and intended for fire-fighting use, whereby the fire extinction water piping extends from the vehicle level to a hy- draulic gun (22) arranged in connection with a working cage (15) and comprises a telescopic water piping section (25) running along the elevating boom system (12) as well as piping sections (28, 23, and 24, 27, 29) located on both sides of the telescopic water piping section, characterised in that a circulating water line (30) provided with a circulation pump (35) is arranged in parallel with the water piping (20), the ends (31, 32) of the circulating water line being connected to the water piping (20) on both sides of its telescopic water piping section (25). 2. The fire extinction water piping according to claim 1, characterised in that the circulating water line (30) is provided with a heater (33). 3. The fire extinction water piping according to claim 1 or 2, characterised in that the outermost pipe (25a) of the telescopic water piping section (25) is enclosed by a heater (26). 4. The fire extinction water piping according to claim 1, 2 or 3, characterised in that the circulating water line (30) is a flexible pressure hose which is arranged to run along a cable rack within or on the outside of the elevating boom system (12). 5. The system intended for preventing the freezing of fire extinction water piping (20) in an elevating platform equipment provided with a telescopic elevating boom system (12), whereby the fire extinction water piping extends from the vehicle level to a hydraulic gun (22) arranged in connection with a working cage (15) and comprises a telescopic water piping section (25) running along the elevating boom sys- tem (12) as well as piping sections (28, 23, and 24, 27, 29) located on both sides of the telescopic water piping section, characterised in that the system comprises a circulating water line (30) provided with a circulation pump (35) to be arranged in parallel with the water piping (20), whereby the ends (31, 32) of the circulating water line are intended to be connected to the water piping (20) on both sides of its telescopic water piping section (25). 6. The system according to claim 5, characterised in that the circulating water line (30) provided with a heater (33) is a flexible pressure hose which is intended to run along a cable rack within or on the outside of the elevating boom system (12). 7. An elevating platform equipment intended for fire-fighting and comprising a turntable (11) supported on a vehicle, a support frame (10), a telescopic elevating boom system (12), swinging booms (14, 16), and a working cage (15) as well as a fire extinction water piping (20) extending from the vehicle level to a hydraulic gun (22) arranged in connection with a working cage (15) and comprising a telescopic water piping section (25) running along the elevating boom system (12) as well as piping sections (28, 23, and 24, 27, 29) located on both sides of the telescopic water piping section, characterised in that a circulating water line (30) provided with a circulation pump (35) is arranged in parallel with the water piping (20), the ends (31, 32) of the circulating water line being connected to the water piping (20) on both sides of its telescopic water piping section (25). 8. The elevating platform equipment according to claim 7, characterised in that the circulating water line (30) is provided with a heater (33). 9. The elevating platform equipment according to claim 7 or 8, characterised in that the outermost pipe (25a) of the telescopic water piping section (25) is enclosed by a heater (26). 10. The elevating platform equipment according to claim 7, 8 or 9, characterised in that the circulating water line (30) is a flexible pressure hose which is arranged to run along a cable rack within or on the outside of the elevating boom system (12).

Inventors: KANGASNIEMI TIMO, MUURIAISNIEMI AIMO, KANGASNIEMI, TIMO, MUURIAISNIEMI, AIMO
Applicants: KANGASNIEMI TIMO, MUURIAISNIEMI AIMO, VEMAST KAARINA OY, KANGASNIEMI, TIMO, MUURIAISNIEMI, AIMO
Application year: 1998
Main classification: A62C27
IPC codes: A62C31, A62C35