Hydrants DN 33

According to European nomenclature, internal hydrants as a part of water supply firefighting installation are fixed firefighting equipment. They enable very effective firefighting thanks to instant access to continuous water supply when they are used in suitable conditions.

Facing modern trends in architecture and individual customer requirements, BOXMET company thanks to innovative solutions and well developed production technology offers a range of products fully compliant with current regulations and legal standards, while providing the functionality and high quality of manufacture.

Modern structural solutions in internal hydrants installed in premises of Polish territory are ensured by the following standards which have been identified as valid by adequate regulation of Ministry of the Interior and Administration Regulation:

• PN-EN 671-1 „Internal hydrants. The technical requirements for internal fire hydrants with semi rigid hose”.
• PN-EN 671-2 „Internal hydrants. The technical requirements for internal fire hydrants with fire hose”.
• PN-EN 671-3 „Internal hydrants. Maintenance of internal hydrants with semi-rigid hose and internal hydrants with hose.
• PN-B-02865:1997/Ap1:1999 „Fire protection of buildings - Fire protection water supply - Fire protection water supply installation".

Boxmet company is a manufacturer of internal fire hydrants with semi rigid hose type DN 25, DN 33 according to norm PN-EN 671-1 and internal hydrants with hose type DN 52 according to PN-EN 671-2.

Guarantee of reliability of internal hydrants manufactured by Boxmet company has been confirmed by the CE CERTIFICATIONS issued by the Scientific Research Centre for Fire Protection in Józefów, near Otwock.

The following materials are used for production of cabinets for hydrants in BOXMET company: black steel plate and stainless steel plate or acidproof stainless steel, with thickness of 0,8 to 1,5 mm. In order to obtain the best effect of performance and durability of cabinets, after cleaning and degreasing on the modern technological line, cabinets are subjected to phosphating treatment, allowing Boxmet company to increase life-span of cabinets, and creates optimal non-metallic surface under applied layer of paint.

Products manufactured by our company are painted using high quality powder paints in two standard colours: red RAL 3000 and white RAL 9016. At customer's request products can be painted in any RAL colour.

Depending on the purpose of products we use the following types of manufacture:

• One layer painting - for installation inside the building,
• Two-layer painting with coat of zinc - for installation outside the building or in areas exposed to moisture,
• Stainless steel plate or acidproof steel (standard material 1.4301).

INTERNAL HYDRANT DN 33 is defined as a device for combating fire, consisting of a hose reel with centrally supplied water, shut-off valve adjacent to reel, semi rigid hose, nozzle with shut-off valve, and if it is necessary, with hose support.

Hydrant in order to be able to work properly, needs to have water pressure on valve no lower than 0,2 MPa. Efficiency of hydrants DN 33, with semi rigid hose should be no less than 1,5 dm³/s (90 l/min).

We use semi rigid rubber hoses in hydrants DN 33 with a nominal diameter of 33 mm. The length of hose in hydrant can be 20m or 30m, in both options hose needs to comprise of one section. Nozzle has a diameter of jet that enables to obtain minimal efficiency of water 1,5 dm³/s (90 l/min), at specified pressure on valve of hydrant. Nozzles used by Boxmet allow to obtain shut current or spray current of water jet.

Semi-rigid hose with inner diameter 33 mm is mounted on a swing reel made of two discs manufactured from black steel plate with thickness of 1,2 mm with reinforcing embossment, separated by distance, which is also support for swivel joint. All the parts are painted with powder paint, RAL3000 red and twisted with bolts.

In hydrants DN 33, screwdown-type DN 50 valves may be used (made of brass as a standard) or quick-opening type DN 32 valves. On the end of connecting hose there is a coupling which enables to reduce diameter of installation DN 50 to inner diameter of semi rigid hose 33 mm.

Flow rate and k- coefficient according to type of nozzles in hydrants DN 33

Nozzle	Diameter of nozzle or diameter of equivalent mm	Flow rate Q			K-coefficient
		p=0,2 MPa	p=0,4 MPa	p=0,6 MPa
BOXMET	10 - shut	1,13 dm3/s	1,58 dm3/s	1,93 dm3/s	48,0
	10 - spray	1,03 dm3/s	1,51 dm3/s	1,85 dm3/s	43,8
BOXMET	12 - shut	1,85 dm3/s	2,68 dm3/s	3,30 dm3/s	78,0
	12 - spray	1,97 dm3/s	2,86 dm3/s	3,60 dm3/s	83,0

Type and length of hose	height	length	width
Basic - without place for fire extinguisher
33H-800-B.20	800	850	425
33H-800-B.30	800	850	425
With place for fire extinguisher in horizontal layout
33H+G-800-B.20	800	1100	425
33H+G-800-B.30	800	1100	425
With place for fire extinguisher in vertical layout
33H+G-1100-B.20	1100	850	425
33H+G-1100-B.30	1100	850	425
Without cabinet
33H-B.20	585	700	385
33H-B.20.SZ	585	638	335
33H-B.30	585	700	435
33H-B.30.SZ	585	638	425