Brochure

Engineering
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G-6
Viscosity Factors
The relationship between kinematic and absolute viscosity:
Centistoke = Centipoise
Specic Gravity
Specic Gravity of Water
Saybolt* Univ
Seconds
(S.S.U.)
Engler Time
Seconds
Kinematic
Viscosity
Correction
Factors (K
1
)
46,350 — 10,000 —
37,080 — 8,000 —
27,810 — 6,000 —
18,540 — 4,000 —
13,900 — 3,000 —
11,590 — 2,500 —
9,270 — 2,000 1.93
6,950 10,800 1,500 1.90
4,635 7,100 1,000 1.82
3,708 5,700 800 1.78
2,781 4,250 600 1.74
1,854 2,820 400 1.67
1,390 2,120 300 1.63
1,159 1,760 250 1.61
927 1,400 200 1.57
695 1,050 150 1.43
464 700 100 1.45
371 555 80 1.42
278 420 60 1.37
186 290 40 1.30
141 225 30 1.25
119 191 25 1.22
97.8 157 20 120
77.4 127 15 1.16
58.9 97 10 1.11
52.1 85.5 8 1.08
45.6 76.0 6 1.07
39.1 67.5 4 1.05
36.0 62.5 3 1.03
32.6 58.0 2 —
31.6 55.5 1.5 —
31.3 ←PURE WATER AT 60°F→ 1.1 —
Chart Note:
*Redwood time (seconds) approximately same as S.S.U.
Temp
T(°F)
Abs.
Pressure
Specic Gravity — S
(W=62.4 lb./ft.
3
@ 60°F)
60 — 1.000 1.000
100 — 0.993 0.999
150 — 0.981 0.985
200 — 0.963 0.981
250 30 0.942 0.971
300 67 0.920 0.959
350 135 0.891 0.944
400 247 0.860 0.927
450 423 0.827 0.910
S
√
Sizing Formulas and Tables
Sizing a Valve
Process Formulas
For Heating or Cooling Water:
GPM = Btu/hr.
(°F water temp. rise or drop x 500)
GPM = CFM x .009 x H
°F water temperature change
(H = change in enthalpy of air expressed in Btu/lb. of air)
For Heating Water with Steam:
lbs. steam/hr. = 0.50 x GPM x (°F water temp. rise)
For Heating or Cooling Water:
GPM
1
= GPM
2
x (°F water
2
temp. rise or drop)
°F water
1
temp. drop
For Heating Air with Steam Coils:
lbs. steam/hr. = 1.08 x (°F air temp. rise) x CFM
1000
For Heating Air with Water Coils:
GPM = 2.16 x CFM x (°F air temp. rise)
1000 x (°F water
1
temp. drop)
For Radiation:
lbs. steam/hr. = 0.24 x ft.
2
EDR (Low pressure steam)
EDR = Equivalent Direct Radiation
1 EDR (steam) = 240 BTU/Hr. (Coil Temp. = 215°F)
1 EDR (water) = 200 BTU/Hr. (Coil Temp. = 197°F)
GPM = ft.
2
EDR
50 (Assume 20°F water TD)