Liquid Distributor Type RD

Transcription

1 MAKING MODERN LIVING POSSIBLE Data sheet Liquid Distributor Type RD The RD refrigerant distributors distribute liquid refrigerants from the thermostatic expansion valve to individual sections of the evaporator. Note! The thermostatic expansion valve must have external pressure equalization. Features y A wide range of RD refrigerant distributors is available, covering the majority of customer demands. y RD design ensures a uniform distribution of refrigerant to each evaporator section. y Suitable for refrigerants R22, R4a, R404A, R407C, R07, R40A. Concerning other refrigerants please contact Danfoss. y Maximum working pressure: MWP/PS 48 bar/700 psig. DKRCC.PD.FF0.A2.02 / 20H74

2 Application example Danfoss 69G8.2 Danfoss 69G Danfoss R Design RD, flare RD, solder ODM. Cone 2. Nozzle. Locking ring 4. Nozzle diameter 2 DKRCC.PD.FF0.A2.02 / 20H74

3 Capacity Table. Capacity in kw for m distributor tube with p = 0. bar Outer diameter of distributor tubes Evaporating temperature t e [ C] / 6 in. / mm / 4 in. / 6 mm / 6 in. / 8 mm / 8 in. / 0 mm R22 / R407C R4a R404A / R07 R40A R22 / R407C R4a R404A / R07 R40A R22 / R407C R4a R404A / R07 R40A R22 / R407C R4a R404A / R07 R40A Table 2. Correction factor for tube length Tube length [mm] Correction Factor Table. Correction factor for liquid temperature Liquid temperature [ C] Correction factor DKRCC.PD.FF0.A2.02 / 20H74

4 Capacity (continued) Danfoss A69-4._FW - C -40 C -4 C -0 C - C -60 C t e = 0 C C 0 C - C -0 C - C -20 C -2 C -0 C R4a, R404A /6 in. / mm R22 /6 in. / mm R22 R4a, R404A /4 in. / 6 mm /4 in. / 6 mm R4a, R404A /6 in. / 8 mm R22 /6 in. / 8 mm R4a, R404A /8 in. / 0 mm R22 /8 in. / 0 mm / 6 in.: ø mm / 4 in.: ø mm / 6 in.: ø mm / 8 in.: ø mm Δp [bar] [kw] Figure It is recommended that distributor tubes are sized for a pressure drop of approx. 0. bar. Table, which gives the capacities for different tube sizes, is based on this pressure drop. Figure shows the relation between evaporator capacity Q e, refrigerant, tube diameter, evaporating temperature t e and pressure drop Δp for m distributor tube. For tube lengths exceeding m, tubes should be selected with larger diameters than indicated in table. 4 DKRCC.PD.FF0.A2.02 / 20H74

5 Ordering RD, flare Table 4 Distributor type Distributor inlet Rated capacity of expansion valves (R407C) Max. number of holes and size of distributor outlet (ODF) / 6 in. / mm / 4 in. / 6 mm / 6 in. / 8 mm RD 2 / 2 in. flare 2 kw (7 TR) 4 RD 27 / 2 in. flare 2 kw (7 TR) 6 / 8 in. / 0 mm RD 2 / 2 in. / 2 mm solder ODM 2 kw (7 TR) 4 RD 27 / 2 in. / 2 mm solder ODM 2 kw (7 TR) 6 RD / 2 in. flare kw (0 TR) 9 6 RD / 2 in. / 2 mm solder ODM kw (0 TR) 9 6 RD, solder RD 42 / 2 in. / 2 mm solder ODM kw (0 TR) 9 RD / 8 in. flare kw (0 TR) RD / 8 in. / 6 mm solder ODM kw (0 TR) RD 42 / 8 in. / 6 mm solder ODM kw (0 TR) 9 7 RD 49 / 8 in. / 6 mm solder ODM 8 kw (2 TR) RD 49 7 / 8 in. / 22 mm solder ODM 8 kw (2 TR) RD 62 7 / 8 in. / 22 mm solder ODM 20 kw ( TR) 8 4 RD 79 ) / 8 in. / 28 mm solder ODM 20 kw (70 TR) 24 9 RD 8 ) / 8 in. / 28 mm solder ODM 00 kw (8 TR) RD 8 ) / 8 in. / mm solder ODM 00 kw (8 TR) ) Replaceable nozzle, for nozzles with other diameters, see table Table. Standard nozzle size Distributor type Nozzle diameter ) [mm] RD 2.0 RD 27.0 RD 6.0 RD RD RD RD RD RD RD RD 8 7. RD 8 8. ) The optimum nozzle diameter depends on the plant conditions. Table 6. Rated capacity correction factor depending on refrigerant (for use in conjunction with table 4) Refrigerant Correction factor R407C.00 R R4a 0.72 R R404A 0.68 R40A.4 DKRCC.PD.FF0.A2.02 / 20H74

6 Type nomenclature Table 7 Type RD Refrigerant Distributor 2 ø2 mm 27 ø27 mm ø mm Body 42 ø42 mm 49 ø49 mm 79 ø79 mm 8 ø8 mm Inlet connector A B C D E H J K L M P Q 2 mm solder ODM 6 mm solder ODM 22 mm solder ODM 28 mm solder ODM mm solder ODM / 2 in. solder ODM / 8 in. solder ODM 7 / 8 in. solder ODM / 8 in. solder ODM / 8 in. solder ODM / 2 in. flare F / 8 in. flare F Nozzle size ## mm Outlet connector A B C D H J K L mm solder ODF 6 mm solder ODF 8 mm solder ODF 0 mm solder ODF / 6 in. solder ODF / 4 in. solder ODF / 6 in. solder ODF / 8 in. solder ODF Number of holes ## 2 27 Example of a type code: RD 2 H 0 J 0 Refrigerant distributor Body Inlet connector Nozzle size Outlet connector Number of holes 6 DKRCC.PD.FF0.A2.02 / 20H74

7 Selection of refrigerant distributor The following data must be known:. Refrigerant 2. Evaporator capacity. Evaporating temperature 4. Liquid temperature. Number of evaporator sections 6. Evaporator section inlet size 7. Distributor tube length 8. Expansion valve type It is then possible to determine: I. Size of distributor tubes The capacity of the individual distributor tube is calculated by dividing the total evaporator capacity by the number of uniform evaporator sections. The tube diameter can then be determined from table or figure. Sizing should be based on the average capacity of the evaporator. A sufficiently uniform distribution can be expected at capacities of between 40% and 2% of the values given in table. Example Given data:. Refrigerant: R404A 2. Evaporator capacity Q e : 20 kw. Evaporating temperature t e : - C 4. Liquid temperature T l : 20 C. Number of evaporator sections: 0 6. Evaporator section inlet size: 6 mm 7. Distributor tube length: 80 mm 8. Expansion valve with 22 mm ODF solder connection on outlet side The capacity of each individual distributor tube is 20 / 0=2.0 kw. Table shows that with an evaporating temperature of - C and R404A, a ø6 mm tube with a length of meter will yield.9 kw. Correction factors for tube length and liquid temperature are found in tables 2 and. For a tube length of 80 mm, the correction factor is.0. For a liquid temperature of 20 C, the correction factor is.24. Under the given conditions, the distributor tubes yield =2.47 kw. The actual load, as a percentage of the listed rating, is thus 2.0 / 2.47=0.8 or 8%. The type of distributor, inlet size and type are determined from table 4. There are two options: RD 49 or RD 62. The rated capacity of the expansion valve can be found using table 6 together with table 4: RD 49: =8 kw RD 62: =82 kw Both distributors can be used, but RD 49 is selected because the rated capacity is closer to the evaporator capacity. The standard nozzle diameter is determined from table : 8 mm. The required distributor type is determined from table 7: RD49-C08-B0. Please contact Danfoss for the code number. DKRCC.PD.FF0.A2.02 / 20H74 7

8 Dimensions [mm] and weights [kg] RD, flare RD, solder ODM Table 8 Distributor type Distributor inlet L L D Approx. net weight Industrial pack RD 2 Flare RD 2 Solder RD 27 Flare RD 27 Solder RD Flare ( 2 in.) RD Solder ( 2 in. / 2 mm) RD Flare ( 8 in.) RD Solder ( 8 in. / 6 mm) RD 42 Solder RD 49 Solder ( 8 in. / 6 mm) RD 49 Solder ( 7 8 in. / 22 mm) RD 62 Solder RD 79 Solder RD 8 Solder DKRCC.PD.FF0.A2.02 / 20H74 Danfoss A/S (AC-MCI / jmn), 20-0