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Flash tank AT 8313

Flash tank for relaxation of the energy content and separation of steam from condensate. Delivered with water trap for connection to floor drain.

Dimension rangeVolume 65 L to 3000 L
Temperature range-10ºC to +180ºC


Article number Height (mm) Diameter (mm) PN Temperature (°C) Volume (Liter) Amount
AT 8313V65 1290 350 0,5 -10 - 180 65
AT 8313V100 1430 400 0,5 -10 - 180 100
AT 8313V150 1665 500 0,5 -10 - 180 150
AT 8313V250 1990 650 0,5 -10 - 180 250
AT 8313V400 2315 650 0,5 -10 - 180 400
AT 8313V500 2375 800 0,5 -10 - 180 500
AT 8313V700 2645 800 0,5 -10 - 180 700
AT 8313V1100 2895 1000 0,5 -10 - 180 1100
AT 8313V1600. 3370 1100 0,5 -10 - 180 1600
AT 8313V2000. 3550 1200 0,5 -10 - 180 2000
AT 8313V3000. 4100 1275 0,5 -10 - 180 3000

Product information

Main Facts

Dimension rangePNTemperature rangeMaterial

65 - 3000 liters

0,5-10 °C to 180 ºCSteel

Range of Application

Pipelines from each safety valve in a boiler plant of a power >100 kW and the temperature >110 º C shall be led to a flash tank. Here the energy content is relaxed and the steam is separated from the condensate. Can also apply to a boiler plant with temperature ≤110º C if the outlet pipelines can not be lead externally without risk of personal injuries or if they should be led vertically e.g. above a roof.


PLC.3 Open Flash tank
Flash tank AT 8313V..... volume .....liters. With ...conn. DN ..... for outlet pipes from safety valves, with conn. DN..... for vent and conn. ..... DN pipes for water outlet.

Quality Assurance

Open vessel, because of this it is free from duty and inspection.

Material Specification

2Cylinder endssteel1.0345
3Water sealsteel1.0345
4Weld endssteel1.0425

Dimension and Weight

D max DN125150200200250300400500600600600
E max DN6580100150200200250250300300300
Measurements in mm, weight in kg.

Function and Design

The outlet pipeline from each safety valve should be connected to the upper side connections of the cylinder. At blow off a mixture of hot water and steam flows into the vessel. Due to the vessel design the relaxed steam separates from the hot water led through the outlet to open air. The hot water drainages from the vessel bottom and leads via a water trap to a floor drain.

The vessel is equipped with an internal display, which prevents the water to go with the steam-flow to open air, a device which facilitates water drainage to the floor drain. The vessel is delivered with water trap for connection to the floor drain.


To be able to dimensioning a flash tank, in terms of volume, connections for vent outlet and water outlet, the following data are necessary:

  • Opening pressure of the safety valve in bar
  • Safety valve's venting capacity of saturated steam in kg / h
  • Estimated length from the vessel top in meters
  • Estimated numbers of pipe bends on the vent pipe
  • Estimated length of the water outlet pipe from water seal to nearest floor drain in meters
  • Estimated numbers of bends on the water outlet pipe

With the above data known, Armatec can make a complete design using a computer program based on the Commission of Pressure Vessel written document, series C35/82.

As a approximate dimensioning the table below can be used.

Dimensioning chart


2 safety valves
Steam pipe
Bottom outlet
Free hight
water seal
Max. steam pipe
kWLiterOutet DNDNDNmm.lenght m.*

* Refer to equivalent pipe lenght. Consideration must be given to bends, etc.

Accessories and Options

The vessel can also be supplied in the performance adapted to Annex 6 "Alternative systems for fusing at temperature ≤ 110 ° C, with power ≤ 900 kW and pressure ≤ 3 bar" in warm- and hot water instructions, VVA 1993.


All connections are welded ends.
The accompanying parts of the water seal can be mounted to the discharge-pipe in optional direction.
For drainage a valve, R 15, is to be mounted at the lowest point.

Maintenance and Spare parts

The vessel is normally maintenance free. However, regular corrosion inspection should be made.


Information about volume, material, year of manufacture and serial number is indicated on the vessel label plate.