Catalogue 3800-MOB/UK
51 Parker Hannifin
Fluid Connectors Group
Thermal valves
Thermal Bypass Valve
max
No Aluminium 1" 1.7 Mpa -30°C NBR, Not Integral Not Not UNF
standard die-cast (250 psi) to FKM applicable relief valve applicable applicable
housing +110°C
Main characteristics
■ Temperature responsive bypass valve to modulate return
line oil between tank and oil cooler.
■ Available in 5 shift temperatures, 38°C to 82°C
(100°F to 180°F)
■ Integral relief valve to dump excessive inlet pressures to the
reservoir. Relief pressure settings available from 0.034 to
0.6 Mpa (5 to 85 psi).
■ 1.7 Mpa (250 psi) maximum operating pressure
■ Up to 227 l/mn (60 GPM US) flow rates
Technical features
Applications
■ Ideally suited for hydrostatic drive circuits which require
fast warm-up, controlled fluid temperatures and low return
line-back pressure.
Modulate fluid temperature by
either shifting return line flow
through the cooler, or by passing
directly to the reservoir.
COOLER
Compact
construction
2 Mounting hole
Ø 10,6 mm
Aluminium die-cast housing
TANK
3 threaded ports
for easy tubing
A built-in pressure relief function
automatically relieves excess pressure to
the reservoir, should the cooler become
restricted and resultant pressure drop
become too high for the cooler circuit
INLET
Catalogue 3800-MOB/UK
52 Parker Hannifin
Fluid Connectors Group
Thermal valves
Thermal Bypass Valve
Operating Sequence
Mode # 1
Cold start-up
Up to 49°C
Mode # 2
Warm-up, shifting
49°C to 63°C
Mode # 3
Fully shifted
Above 63°C and
below 0.52 Mpa
Mode # 4
High pressure
Above 63°C and
above 0.52 Mpa
Cooler
Tank
Inlet
Cooler
Tank
Inlet
Cooler
Tank
Inlet
Cooler
Tank
Inlet
Fluid Flow Example with:
A. 49°C Opening
Temperature
B. 0.52 Mpa Integral
Relief
Fluid Flow =
Excess Pressure =
A. Mode #1:
At temperatures below
the shift temperature oil
flows inlet to tank port.
B. Mode #2:
At temperatures between
the start of shift and full shift
the flow from the inlet port
is divided between the cooler
and tank ports.
C. Mode#3:
At temperatures above the
full shift temperature inlet
flow is through cooler port.
D. Mode #4:
At temperatures above
the full shift temperature
the excess pressure is
relieved through the tank
port.
- Standards Shift Temperatures:
100°F (38°C), 120°F (49°C), 140°F (60°C), 160°F (71°C), 180°F (82°C)
- Full shift (cooler port open) Temperature:
Shift temperature plus 25°F (14°C)
- Relief Valve Setting:
Up to 0.6 Mpa (6 bar) in 0.035 Mpa increments
- Proof Pressure:
2.1 Mpa (21 bar)
- Operating Fluid:
Mineral base hydraulic fluids
- Leakage at 1.7 Mpa (17 bar) and 227 l/min (60 gpm) inlet flow:
• Cooler port:
- 2 l/min (0.5 gpm) max. up to 3°C (5°F) before shift temperature
- 4 l/min (1 gpm) max. from 3°C (5°F) before shift to shift
• Tank Port:
- 0.4 l/min (0.1 gpm) maximum
Body size Minimum Max.operating Rated Proof pressure Minimum burst Minimum burst Max. flow
inch Operating pressure pressure pressure up to pressure above rating
temperature temperature the full shift the full shift
temperature temperature
1" -30°C Shift 1.7 Mpa 2.1 Mpa 2.2 Mpa 4.1 Mpa 227 l/min
temperature
plus 24°C
(75°F)
CoolerReservoir
Inlet
Technical performance data
Catalogue 3800-MOB/UK
53 Parker Hannifin
Fluid Connectors Group
Thermal valves
Thermal Bypass Valve
Dimensions and part numbers
66.5
Ref.
138.2
66.5
A
8.3
8.2
30.2
Inlet port
Ø 10.7
Mounting holes
2-Places
Section A-A
38.8
73.0
89.2
44.8
47.8
Cooler port
Tank port
1
5/16-12
UN
O-Ring boss
SAE J1926-16
3 - Places
A
Pressure drop
Flow - (l/min)
Inlet port through Tank port
©
38°C
Test with oil viscosity 64 cst
Pressure drop (Mpa)
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
0 25 50 75 100 125 150 175 200 225 250
Flow - (l/min)
Inlet port through Cooler port
©
63°C
Test with oil viscosity 23 cst
Pressure drop (Mpa)
0.14
0.12
0.10
0.08
0.06
0.04
0.02
0
0 25 50 75 100 125 150 175 200 225 250
Flow - (l/min)
Inlet port over Integral relief valve
©
77°C
Test with oil viscosity 16 cst
Pressure drop (Mpa)
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
0 25 50 75 100 125 150 175 200 225 250
Note: Pressure drop shown is added to relief valve crack pressure for total pressure drop.
Catalogue 3800-MOB/UK
54 Parker Hannifin
Fluid Connectors Group
Thermal valves
Thermal bypass valve
Final dash code No. code
Crack Shift temperatures °C
pressure
Mpa 38°C49°C60°C71°C82°C
0.035 -01 -21 -41 -61 -81
0.070 -02 -22 -42 -62 -82
0.105 -03 -23 -43 -63 -83
0.140 -04 -24 -44 -64 -84
0.170 -05 -25 -45 -65 -85
0.210 -06 -26 -46 -66 -86
0.240 -07 -27 -47 -67 -87
0.275 -08 -28 -48 -68 -88
0.310 -09 -29 -49 -69 -89
0.345 -10 -30 -50 -70 -90
0.380 -11 -31 -51 -71 -91
0.415 -12 -32 -52 -72 -92
0.450 -13 -33 -53 -73 -93
0.485 -14 -34 -54 -74 -94
0.520 -15 -35 -55 -75 -95
0.550 -16 -36 -56 -76 -96
0.585 -17 -37 -57 -77 -97
Final dash No. code
TH - 1000 - 16FO - XX
Crack pressure / Temperature code
See chart below
Thermal Valve size Port
bypass combination
valve Series
Example : TH-1000-16FO-48
Indicates 0.28 Mpa relief crack pressure and 60°C shift temperature
Body size Thread A Part number Weight
inch inch female body gr./piece
1" 1 5/16-12 UN TH-1000-16FO-* 907
Note: For 2" Thermal bypass valve or other thread options, please contact your Parker sales engineer.
