JPS5824708Y2 - fire hose - Google Patents

Description

[Detailed description of the invention] The present invention relates to a fire hose, and particularly when applied to a large-diameter fire hose with an inner diameter of 75 threads or more, it provides a light and flexible fire hose that can withstand high pressure. It is something to do.

Conventionally used fire hoses have a tubular woven fabric jacket lined with flexible rubber or synthetic resin, and the warp of the jacket is usually made of vinylon or polyester fiber spun yarn. The weft is made of long-staple polyester fiber yarn.

A fire hose with this structure is manufactured with an inner diameter of 6511E and a working pressure of 16 kg/cIIL21.

However, in recent years, with advances in firefighting technology, there has been a demand for pipes that can deliver even larger amounts of water, and larger diameter pipes that can withstand higher pressures have also come to be required.

Incidentally, fire hoses follow the example of general thin-walled inner pipes, and as the inner diameter becomes larger, the withstand pressure decreases in inverse proportion to this.

In the case of fire hoses, the warp threads originally have a considerable margin in terms of strength, and it is relatively easy to increase the warp threads, so there is little problem, but it is mainly necessary to strengthen the weft threads, which bear the burden of pressure resistance. It is extremely difficult to expand the inner diameter without reducing pressure resistance.

In other words, if the inner diameter is increased, it is necessary to increase the number of weft threads in proportion, but increasing the number of weft threads creates a jamming structure, which not only limits the increase, but also makes the jacket stiffer. , it becomes extremely difficult to handle.

In particular, the inner diameter of the hose (crIL) and the working pressure (kg/cI)
This tendency becomes remarkable when the product with IL2) exceeds 100 kg/cIrLf, and the aforementioned one with an inner diameter of 6511N and a working pressure of 16 kg/cm2 was said to be the limit.

Since fire hoses are generally used under high pressure, their performance and structure are strictly defined by national standards for safety.

Pressure resistance is particularly strict, and tests are conducted at twice the working pressure.Furthermore, for safety reasons, it is common knowledge for manufacturers to design the hose structure to have a pressure three to four times the breaking pressure. It has become.

Therefore, for a hose with a working pressure of 16 kg/cm2, its design breaking pressure is about 50 kg/cIrL2, and this is where the above-mentioned limitations in jacket manufacture arise.

In some cases, products with larger inner diameters and higher operating pressures are manufactured, but in order to solve the above-mentioned problems, it is better to use thicker thread as the weft thread and reduce the number of threads. The reality is that we have barely achieved the desired performance.

FIG. 1 is a vertical cross-sectional view schematically showing this conventional fire hose, which has a structure in which a lining 4 of rubber or synthetic resin is applied to the inner surface of a jacket 3 woven with thick weft yarns 1 and warp yarns 2. It shows.

In this structure, the weft yarn 1 has a nearly circular cross-section because the weft spacing is small compared to the thickness of the weft yarn, and the weft yarn 2 meanders around it, forming the jacket 3. Severe unevenness is formed on the inner and outer surfaces.

When the lining 4 is applied to the inner surface of such a jacket 3, the lining 4' formed on the convex portions 5 of the weave becomes very thin, which not only makes it easy for pinholes to occur in this area, but also makes the weave Because the lining is formed along the unevenness of the hose, the inner surface of the hose has a highly uneven shape, which increases water flow resistance.

In order to eliminate these drawbacks, the lining must be made thicker than necessary, and the hose must be thick, heavy, and hard, making it difficult to handle.

The present invention was developed in view of the above circumstances, and by using aromatic polyamide fiber for the weft thread 1 of the jacket, the product of the inner diameter and the working pressure is 100 kg/cr.
To provide a fire hose that can be made fL or more, has a pressure resistance performance even if it has a large diameter of 75 or more, and is light, flexible, and easy to handle.

FIG. 2 is a vertical sectional view schematically showing the fire hose of the present invention.

6 is a weft made of long fiber yarn of aromatic polyamide fiber with low elongation.

This aromatic polyamide fiber is a synthetic fiber having extremely high tensile strength and low elongation, and for example, Kevlar, a trade name manufactured by DuPont, is known.

7 is a warp yarn made from spun yarn of synthetic fibers such as vinylon and polyester fibers.

The weft yarn 6 and the warp yarn 7 have a plain weave structure and are woven into a cylindrical shape to form a jacket 8.

9 is a flexible rubber or synthetic resin lining.

In the fire hose of the present invention, strong aromatic polyamide fibers are used for the weft, so the weft is thinner than that of conventional hoses.

As a result, it is inserted into the structure of the jacket and deformed by being caught in the warp yarns, resulting in a flat elliptical shape.

As a result, the overall thickness of the jacket becomes thinner, and the degree of bending of the warp yarns that are organized with the weft yarns is small, and the jacket does not have severe irregularities.

Therefore, the lining 9 has sufficient thickness even at the convex portions of the jacket and does not produce pinholes, and since the inner surface of the lining has only smooth irregularities, the resistance to water flow is small.

Below is the specific structure of the fire hose according to the present invention,
A comparison with the corresponding conventional hose is shown.

As shown in this table, the fire hose of the present invention is lighter than the conventional one.

This weight is not only reduced by reducing the amount of yarn used in the jacket, but also by reducing the amount of rubber in the lining, resulting in a significant reduction in overall weight.

Moreover, despite the reduced amount of rubber, the minimum lining thickness is greater than that of conventional fire hoses, reducing the possibility of pinholes.

Compared to conventional fire hoses, which are rigid due to the dense weave of the jacket and have a large coil winding diameter, they are heavy and difficult to handle, whereas the fire hose of this invention is flexible, light, and small. Since it can be wound into a coil with the same diameter, it is easy to handle and convenient to store.

Furthermore, although the two types of fire hoses shown in the above-mentioned jackets are designed so that the same withstand pressure can be obtained, the breaking pressure of the present invention is nevertheless higher.

This is because the elongation at break of aromatic polyamide fiber (Kevlar) is much smaller than that of polyester fiber.
The inner diameter of the fire hose that clicks when it breaks is better with this invention.
It is thought that it is small and can withstand higher pressure.

Therefore, in the present invention, when designing the structure of the jacket, there is no need to consider the elongation of the weft yarn and apply a safety factor, and in reality, it is possible to further reduce the weight.

As mentioned above, even if the fire hose of the present invention has a large diameter of 75U or more, it is flexible, light, and easy to handle, and can be lined with a sufficient thickness, so it does not cause pinholes. It has many advantages, such as the fact that the inner surface of the lining is relatively smooth and the resistance to water flow is small.

In addition, in this invention, the product of the inner diameter and the working pressure is 100 kg/
It is preferable to apply this method to hoses having crrL or more.

If aromatic polyamide fibers are used for the weft in hoses in which this weight is less than 100 kg/crrL, the thickness of the weft becomes excessively thin because the fibers are strong.

For this reason, it is not only too flexible and difficult to handle as a hose, but also causes kinging during use, which actually reduces its performance as a fire hose.

Further, it is also not preferable to use aromatic polyamide fibers for the warp yarns of the jacket.

In other words, not only does the hose become expensive, but aromatic polyamide fibers do not have good weather resistance or abrasion resistance, so using them for the warp of a jacket that is exposed to the outside reduces the performance of the hose. There is a button.

Moreover, since the elongation of the hose in the longitudinal direction is extremely small, water hammer phenomenon is likely to occur when water starts flowing.
Even if it is applied to low pressure, there is a risk of it breaking, which is not desirable.

[Brief explanation of drawings]

FIG. 1 is a schematic vertical cross-sectional view of a conventional fire hose, and FIG. 2 is a schematic vertical cross-sectional view of the fire hose of the present invention. 6...Weft, 7...Warp, 8...
... Jacket, 9 ... Lining.

Claims (1)

[Scope of utility model registration request] A fire hose characterized by having a flexible rubber or synthetic resin lining on the inner surface of a jacket made of a cylindrical weave of synthetic fiber warp yarns such as vinylon, polyester, etc. and aromatic polyamide fiber weft yarns.