volume-type floating coil heat exchanger
1. Overview BFDL/W volume-type floating coil heat exchanger is a combination of BFDB half-hot floating coil heat exchanger and the general volume heat exchanger.It has big storage,and hot water suppl...
BFDL/W volume-type floating coil heat exchanger is a combination of BFDB half-hot floating coil heat exchanger and the general volume heat exchanger.It has big storage,and hot water supply is security and stability.Meanwhile it owns features of high heat efficiency and noise-free.
High heat transfer coefficient:BFDL/W heat exchanger possesses the same characteristics of heat transfer as floating coil heat exchanger,the heat transfer coefficient can reach from 2600 to 4000 W/m2•℃(steam-water heat exchange)and 1800~3000W/m2•℃(water-water heat exchange).
The high utilization rate of volume:Considering the characteristics of the hydraulic cycle,we install heating pipe in low position in order to make the water from the Shell cycle smoothly,and no segregation of cold and heat,no cold water area.The volume utilization can reach up to 100%.
Scale prevention:BFDL/W-floating coil heat exchanger also uses double helix coil structure and possesses outstanding removing scale function.No manual cleaning work.
Convenient maintenance:It adopts the removable structure design so it is convenient for maintenance and replacement.
Two. Type description
Three. Technical parameters
Four. Design and type selection
BFD floating coil heat exchanger applies to the steam or hot water heat exchange media system that could fully replace the aged type.BFDL/W volume-floating coil heat exchanger has big storage and stable water supply.
1．Some elements should be determined when designing:heating media inlet and outlet temperature,refrigerant inlet and outlet temperature and flow,heat load etc.Then the heat exchange area will be calculated as follows:
Q-Heat load W;K-coefficient of heat transfer W/m2•℃;F-heat transfer area m2;
△t-difference of heat transfer temperature℃;
Convert to model selection formula:F=Q(ε?K?△t)
(1)Heat load Q：Depending on actual program requirement.
(2)Coefficient of heat transfer K:Taking the coefficient range recorded before as reference.
(3)Difference of heat transfer temperature△t:In generally it is estimated by calculated average temperature.
T1,T2-heat media inlet and outlet temperature℃
t1,t2-refrigerant inlet and outlet temperature℃
(When steam-water heating,it is more precise to separate to calculate steam-water mean temperature and water-water mean temperature)
（4）Dirt correction factor:0.7~0.9 is common,take the small one.
2.Selecting suitable operating pressure according to pressure-bearing condition of heat exchanger.
3.According to the program actual condition to decide the quantity of heat exchangers to guarantee successive and stable operation.
4.The actual area of heat exchanger should bigger than calculated area,and considering some margin.
Five. Installation and use
About BFD series installation of floating-coil heat exchanger,please refer to the relevant state standards and norms.
1.BFD heat exchanger should be installed on the flat basis,considering connecting pipe maintenance convenience.
2.When installation,according to the drawings corresponding to connect pipeline.The safety valve should meet the requirements of the use of a safety valve.And the pressure gauge,thermometer should have sufficient range.
3.Selecting the temperature control device depends on the actual need,and the heat exchanger should be thermal insulation.
4.Regular sewage is necessary.
5.Adopting heat effect to remove the Scale on the coil:
(1)To drain off water in the coil;
(2)To open the steam valve then the temperature of coil increased and producing sound which should be lasted for about five minutes;
(3)Close steam valve and open water valves to cool coil rapidly,result in that the scale will fall off.
(4)Open sewage valve to discharge the dropped scale.Repeat this operation 3 to 5 times and can be totally removed Scale.