What Are Fire Protection Contractors?

Fire-fighting pipes refer to pipeline materials used for fire-fighting, connecting fire-fighting equipment, equipment, and conveying fire-fighting water, gas, or other media. Due to special requirements, there are special requirements for the thickness and material of fire fighting pipes, and red paint is sprayed to transport fire fighting water.

Fire pipe

Fire-fighting pipes refer to pipeline materials used for fire-fighting, connecting fire-fighting equipment, equipment, and conveying fire-fighting water, gas, or other media. Due to special requirements, there are special requirements for the thickness and material of fire fighting pipes, and red paint is sprayed to transport fire fighting water.

Chinese name

Fire pipe

Foreign name

fire pipeline

Features

Good resistance to pressure, corrosion and high temperature

Meaning

Refers to piping materials used in fire protection

Because the fire protection pipeline is often in a static state, the requirements for the pipeline are relatively strict. The pipeline needs pressure resistance, corrosion resistance, and high temperature resistance.

Ductile iron cast iron pipe,

Preparation for installation installation of main pipe installation of alarm valve installation of vertical pipe installation of sprayed dry branch pipe, fire hydrant and branch pipe installation of water flow indicator, fire pump, high-level water tank, water pump coupler pipeline test pipeline flushing sprinkler head Branch pipe installation (system comprehensive pressure test and flushing) Throttling device installation Alarm valve fittings, fire hydrant fittings, sprinkler head installation System water test

1.General requirements

(1) When the hydrant water supply system pipes are hot-dip galvanized steel pipes on the inner and outer walls, welding shall not be used. When the system pipes are non-corrosion-proof pipes on the inner wall, they can be welded and connected, but the pipe welding should meet the relevant requirements. Pipes of sprinkler systems (after the alarm valve) cannot be welded. They should be threaded, grooved pipe joints or flanged connections.

(2) Galvanized steel pipes with a diameter of 100mm for the hydrant water supply system shall be flanged or grooved. The pipe diameter of the sprinkler system mm100mm is not clear. Thread connection is not allowed. It is only required that a flange connection or a groove connection point should be provided at a certain distance on the pipe section 100mm.

(3) For hydrant water supply system and sprinkler system pipes, threaded flanges are recommended when flanged, and secondary galvanized should be used when welded flanges are used.

(4) When the pipe diameter needs to be changed for any pipe section, reducers and fittings that meet the standards shall be used.

(5) For the connection methods of fire fighting pipelines and related technical requirements, please refer to the relevant provisions in "National Civil Engineering Construction Design Technical Measures-Water Supply and Drainage".

2. Grooved (clamp) connection

(1) The depth of grooved joints (pipe joints) and steel pipe grooves shall comply with the regulations of "Groove pipe joints" (CJJ / T156-2001). The maximum working pressure of a grooved pipe joint with a nominal diameter DN 250mm is 2.5 MPa, and the maximum working pressure of a grooved pipe joint with a nominal diameter DN 300mm is 1.6 MPa.

(2) Flexible joints should be used in places subject to vibration and buried pipelines. Steel joints should be used in other places. When steel joints are used, a flexible joint should be provided every 4 to 5 steel joints.

3.Threaded connection

(1) The inner and outer hot-dip galvanized steel pipes or the inner and outer hot-dip galvanized seamless steel pipes with pipe diameters <DN100 in the system can be threaded. When the system uses hot-dip galvanized steel pipes on the inner and outer walls, the pipe fittings can use forged cast iron threaded pipe fittings (GB3287 ~ 3289); when the system uses hot-dip galvanized seamless steel pipes on the inner and outer walls, the pipe fittings can use forged steel thread pipe fittings (GB / T14626 ).

(2) If the wall thickness of the steel pipe is less than <Sch30 (DN200mm) or the wall thickness is less than <Sch40 (DN <200mm), no threaded connection is allowed.

(3) When the pipe adopts 55 ° tapered pipe thread (Rc or R), the thread interface can be sealed with PTFE; when the pipe adopts 60 ° tapered pipe thread (NPT), sealant should be used as the seal of the thread interface ; The sealing tape should be applied on the male thread.

(4) Pipes with a diameter of> DN50 shall not use threaded unions, and single-diameter reducers shall be used where the pipe diameter is reduced.

4, welding or flange joints

(1) Flange types can be divided into: flat welding flanges, bimetal welding, butt welding flanges and threaded flanges according to the connection type.

With the current development requirements, various new types of fire-fighting pipes and connection technologies continue to appear and are effectively applied in various practical projects. These need to be summarized, so that various fire-fighting pipes are more widely used in various fire-fighting system applications. Accurate and economical.

This part of GB 5135 specifies the requirements, test methods, inspection rules, packaging, transportation and storage of coated steel pipes for sprinkler systems. This section applies to coated steel pipes with an internal coating material with a nominal diameter of not more than 300 mm in an automatic sprinkler system. ^[2]

"National Standard Automatic Sprinkler System Part 20: Coated Steel Pipe"

"Technical Regulations for Pipeline Engineering of Building Water-supply Composite Pipe"

"Code for Acceptance of Construction Quality of Building Water Supply and Drainage and Heating Engineering"