Technical Information
DDC Axial Piston Pumps
Size 20/24
www.danfoss.com
Technical Information
DDC Axial Piston Pumps Size 20/24
Revision history |
Table of revisions |
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Date |
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Changed |
Rev |
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February 2022 |
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Added Option: Detent |
0309 |
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December 2021 |
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Minor fix on Design Specifications |
0308 |
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November 2021 |
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Added notes at Diagrams and LFV. |
0307 |
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October 2021 |
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Added table on CPRV |
0306 |
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September 2021 |
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Added to CPRV and Model Code: L. |
0305 |
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March 2021 |
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Minor update in Input Shafts AB, BB, DB |
0304 |
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January 2021 |
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Minor update in Performance Specifications |
0303 |
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November 2020 |
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Minor update in Fluid selection |
0302 |
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August 2020 |
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Update CPRV setting |
0301 |
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June 2020 |
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Changed document number and version from 'BC00000191' and 'L1104976' to |
0201 |
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'BC152886484876' |
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August 2019 |
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Minor typo |
0105 |
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June 2019 |
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Added Size 24 |
0104 |
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December 2018 |
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Corrected rounding error in performance specifications |
0103 |
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February 2017 |
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Change charge pump housing |
0102 |
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January 2016 |
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Add SAE-A, 13T Auxiliary Pad Option |
0101 |
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April 2015 |
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Minor update in Model Code |
BB |
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March 2015 |
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Add Implement Pump and SAE A Mounting Flange Options, and Converted to Danfoss |
BA |
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layout - DITA CMS |
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March 2013 |
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Paint and Tag |
AC |
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November 2011 |
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Minor edits |
AB |
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October 2011 |
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First edition |
AA |
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2 | © Danfoss | February 2022 |
BC152886484876en-000309 |
Technical Information |
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DDC Axial Piston Pumps Size 20/24 |
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Contents |
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General Description |
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Design................................................................................................................................................................................................... |
5 |
Key Features....................................................................................................................................................................................... |
5 |
Typical Applications........................................................................................................................................................................ |
5 |
System Diagram................................................................................................................................................................................ |
6 |
Schematic Diagram.......................................................................................................................................................................... |
7 |
Technical Specifications |
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Design Specifications...................................................................................................................................................................... |
8 |
Performance Specifications.......................................................................................................................................................... |
8 |
Operating Parameters..................................................................................................................................................................... |
9 |
Fluid Specifications.......................................................................................................................................................................... |
9 |
Operation |
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High Pressure Relief / Check Valve (HPRV)............................................................................................................................ |
10 |
High pressure relief / check valve with orifice............................................................................................................... |
10 |
Bypass Function.............................................................................................................................................................................. |
11 |
Charge Pressure Relief Valve (CPRV)....................................................................................................................................... |
12 |
Loop flushing valve....................................................................................................................................................................... |
13 |
Control............................................................................................................................................................................................... |
14 |
Direct Displacement Control................................................................................................................................................ |
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Control Handle Requirements............................................................................................................................................. |
14 |
Operating Parameters |
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Overview........................................................................................................................................................................................... |
15 |
Input speed...................................................................................................................................................................................... |
15 |
System pressure............................................................................................................................................................................. |
15 |
Charge pressure.............................................................................................................................................................................. |
15 |
Charge pump inlet pressure...................................................................................................................................................... |
16 |
Case pressure................................................................................................................................................................................... |
16 |
Temperature.................................................................................................................................................................................... |
16 |
Viscosity............................................................................................................................................................................................. |
16 |
System Design Parameters |
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Filtration system ............................................................................................................................................................................ |
17 |
Filtration............................................................................................................................................................................................ |
18 |
Suction filtration....................................................................................................................................................................... |
18 |
Charge pressure filtration...................................................................................................................................................... |
18 |
External Pressure Filtration................................................................................................................................................... |
19 |
Independent braking system.................................................................................................................................................... |
19 |
Fluid Selection................................................................................................................................................................................. |
19 |
Reservoir............................................................................................................................................................................................ |
19 |
Case Drain......................................................................................................................................................................................... |
19 |
Charge Pump................................................................................................................................................................................... |
20 |
Charge Pump Sizing/Selection............................................................................................................................................ |
20 |
Charge Pump Output Flow........................................................................................................................................................ |
20 |
Implement Pump........................................................................................................................................................................... |
21 |
Bearing Loads and Life................................................................................................................................................................. |
23 |
Applications with External Shaft Loads............................................................................................................................ |
23 |
Input Shaft................................................................................................................................................................................... |
23 |
Shaft Torque..................................................................................................................................................................................... |
24 |
Mounting Flange Loads............................................................................................................................................................... |
25 |
Estimating Overhung Load Moments............................................................................................................................... |
25 |
Understanding and minimizing system noise..................................................................................................................... |
26 |
Size Equations................................................................................................................................................................................. |
27 |
Model Code |
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Model Code: A, B, R, C, E, G, M................................................................................................................................................... |
28 |
Model Code: H, K, F........................................................................................................................................................................ |
29 |
Model Code: J, S, L......................................................................................................................................................................... |
30 |
Model Code: N, P, Y, Z................................................................................................................................................................... |
31 |
© Danfoss | February 2022 |
BC152886484876en-000309 | 3 |
Technical Information |
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DDC Axial Piston Pumps Size 20/24 |
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Contents |
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Installation Drawings |
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With Aux-Pad, No Charge Pump, Left Trunnion, SAE A Flange Configuration........................................................ |
32 |
With Aux-Pad, No Charge Pump, Left Trunnion, SAE B Flange Configuration........................................................ |
34 |
With Charge Pump, No Aux-Pad, Left Trunnion, SAE A Flange Configuration........................................................ |
36 |
With Charge Pump, No Aux-Pad, Left Trunnion, SAE B Flange Configuration........................................................ |
38 |
With Implement Pump, No Aux-Pad, Left Trunnion, SAE A Flange Configuration................................................ |
40 |
With Implement Pump, No Aux-Pad, Left Trunnion, SAE B Flange Configuration................................................ |
42 |
Option: Detent................................................................................................................................................................................ |
44 |
Input Shafts: AA, BA, DA.............................................................................................................................................................. |
45 |
Input Shafts: AB, BB, DB............................................................................................................................................................... |
46 |
Input Shafts: AC, BC, DC............................................................................................................................................................... |
47 |
Auxiliary Mounting Pads............................................................................................................................................................. |
48 |
Reference Literature |
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Literature........................................................................................................................................................................................... |
50 |
4 | © Danfoss | February 2022 |
BC152886484876en-000309 |
Technical Information
DDC Axial Piston Pumps Size 20/24
The DDC pump is a compact and lightweight variable displacement axial piston pump intended for use in closed circuit low to medium power applications. DDC pump is a direct displacement control pump utilizing an advanced slipper piston design. The flow rate is infinitely variable between zero and maximum. The direction of flow is commanded by tilting the swashplate in one direction or the other from the neutral (zero flow) position. Reversing the direction of flow reverses the direction of motor rotation.
•Displacement 20/24 cm3/rev [1.22/1.46 in3/rev]
•Optional bypass valve and loop flushing valve
•Optional integral charge pump / Implement pump
•Compact design with best in class pressure ratings and durability
•Low noise
•Backed by a global network of Danfoss service provider
•Mounting flange (SAE-A / B)
•Turf Care
‒Greens Mower
‒Zero Turn Radius Mower
‒Loaders
•Utility Vehicles
•Compact Agricultural Machinery
•Small Compactors
•Compact Construction Equipment
DDC Pump Cross-Sectional View
Trunnion
Valve plate |
Piston |
Slipper |
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Charge pump |
Charge pressure relief valve Ball bearing
Input shaft
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Swashplate |
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Endcap |
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Needle bearing |
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Check and high pressure relief valve |
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Bypass valve |
P400023 |
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© Danfoss | February 2022 |
BC152886484876en-000309 | 5 |
Technical Information
DDC Axial Piston Pumps Size 20/24
General Description
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Heat exchanger |
Reservoir |
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bypass |
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Filter |
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Heat |
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exchanger |
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Charge pressure relief |
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Cylinder |
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valve |
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block |
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OMR |
assembly |
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orbital |
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motor |
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Charge pump |
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Output |
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shaft |
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Suction flow |
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Input |
Variable |
High pressure relief/ |
Loop flushing valve |
Working Loop (Low Pressure) and |
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shaft |
displacement |
check valves |
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Charge Pressure |
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pump |
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Working Loop (High Pressure) |
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Case flow |
P400024 |
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Loop flushing valve and Charge pump cannot be used together in one pump.
6 | © Danfoss | February 2022 |
BC152886484876en-000309 |
Technical Information
DDC Axial Piston Pumps Size 20/24
General Description
L3 |
M3 |
MA |
A
B
L1 |
L2 |
S |
MB |
P400025 |
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Loop flushing valve and Charge pump cannot be used together in one pump.
© Danfoss | February 2022 |
BC152886484876en-000309 | 7 |
Technical Information
DDC Axial Piston Pumps Size 20/24
Features |
DDC pump |
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Design |
Axial piston pump of journal trunnion design with variable displacement |
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Direction of input rotation |
Clockwise or counterclockwise |
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Pump installation position is discretionary, however the recommended trunnion position |
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is on the side or at the bottom. |
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If mounted with trunnion shaft position upward, water and dust tend to collect around |
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Recommended installation position |
the shaft, which may accelerate the deterioration of the shaft seal. |
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Vertical input shaft installation is acceptable. The housing must always be filled with |
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hydraulic fluid. Recommended mounting for a multiple pump stack is to arrange the |
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highest power flow towards the input source. |
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Consult Danfoss for nonconformance to these guidelines. |
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Filtration configuration |
Suction or charge pressure filtration |
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Other system requirements |
Independent braking system, suitable reservoir and heat exchanger |
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Control type |
Direct displacement control |
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Features |
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Units |
DDC20 |
DDC24 |
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Displacement1 |
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cm3/rev [in3/rev] |
0-20.0 [0-1.22] |
0-24.0 [0-1.46] |
Mass moment of inertia of rotating components |
kg•m2 [slug•ft2] |
0.0009 [0.0006] |
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With charge pump |
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10 [22.1] |
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Weight dry |
With implement pump |
kg [lb] |
11 [24.3] |
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With auxiliary pad |
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12 [26.4] |
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Oil volume |
Case only |
liter [US gal] |
0.7 [0.1] |
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Mounting flange |
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ISO3019-1 flange 101-2 (SAE B), 2 bolt |
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ISO3019-1 flange 82-2 (SAE A), 2 bolt |
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Input shaft outer diameter, Splines, key shafts2 |
ISO 3019-1, outer dia 22mm-4 (SAE B, 13 teeth) |
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ISO 3019-1, outer dia 22mm-1 (Straight Key, Ls) |
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ISO 3019-1, outer dia 22mm-1 (Straight Key, Special length) |
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ISO 3019-1, flange 82 - 2, outer dia 16 mm - 4 |
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Auxiliary mounting flange with metric fasteners, shaft outer |
(SAE A, 9 teeth) |
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diameter and splines |
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ISO 3019-1, flange 82 - 2, outer dia 19 mm - 4 |
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(SAE A, 11 teeth) |
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Suction ports |
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ISO 11926-1, 7/8 -14 (SAE O-ring boss) |
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Main port configuration |
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ISO 11926-1, 7/8 -14 (SAE O-ring boss) Twin port, radial |
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Case drain ports L1, L2 , L3 |
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ISO 11926-1, 3/4 -16 (SAE O-ring boss) |
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Other ports |
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See Installation Drawings on page 32 |
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Customer interface threads |
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Metric fasteners |
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1Max Swashplate angle is 18 degrees.
2See Installation Drawings on page 32 for mounting flange SAE A.
8 | © Danfoss | February 2022 |
BC152886484876en-000309 |
Technical Information
DDC Axial Piston Pumps Size 20/24
Technical Specifications
For definitions of the following specifications, see Operating Parameters on page 15
Features |
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Units |
DDC pump |
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Minimum for internal charge |
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500 |
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supply1 |
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Input speed |
Minimum for external |
min-1 (rpm) |
500 |
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charge supply |
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Rated |
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4000 |
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Maximum |
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4500 |
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Maximum working pressure |
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300 [4350] |
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System pressure |
Maximum pressure |
bar [psi] |
345 [5004] |
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Minimum low loop (above |
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4 [58] |
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case) |
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Charge pressure (minimum) |
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bar@15 lpm [psi/USG] |
7 [101] |
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Minimum (continuous) |
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0.8 [6] |
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Charge pump inlet pressure |
Minimum (cold start) |
bar (absolute) [in Hg vacuum] |
0.2 [24] |
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Maximum |
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2.0 |
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Case pressure |
Rated |
bar [psi] |
1.5 [21.7] |
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Maximum |
3 [43.5] |
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1 No load condition. Refer to System Design Parameters/Charge Pump on page 20 for details.
Features |
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Units |
DDC pump |
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intermittent1 |
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5 [42] |
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Viscosity |
Minimum |
mm2/sec. [ SUS] |
7 [49] |
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Recommended range |
12 - 80 [66 - 370] |
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Maximum (cold start)2 |
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1600 [7500] |
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Maximum (cold start) |
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-20 |
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Temperature range3 |
Recommended range |
°C |
60 - 85 |
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Maximum continuous |
104 |
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Maximum intermittent |
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115 |
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Cleanliness per ISO 4406 |
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22/18/13 |
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Efficiency (charge pressure |
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β15-20=75(β10≥10) |
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Filtration (recommended |
filtration) |
β-ratio |
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minimum) |
Efficiency (suction filtration) |
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β35-45=75(β10≥2) |
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Rercommended inlet screen |
µm |
100 - 125 |
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mesh size |
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1Intermittent=Short term t <1 min per incident and not exceeding 2 % of duty cycle based load-life.
2Cold start = Short term t < 3 min, p < 50 bar [725 psi], n < 1000 min-1 (rpm)
3At the hottest point, normally case drain port.
© Danfoss | February 2022 |
BC152886484876en-000309 | 9 |
Technical Information
DDC Axial Piston Pumps Size 20/24
The DDC pump is equipped with a combination high pressure relief and charge check valve. The high pressure relief valve (HPRV) function is a dissipative (with heat generation) direct acting pressure control valve for the purpose of limiting excessive system pressures. Each side of the transmission loop has a non-adjustable HPRV valve. When system pressure exceeds the factory setting of the valve, oil flows into the charge gallery. The valve is a differential pressure device working with system and charge pressure. The charge check function acts to replenish the low-side working loop with oil any time the low loop pressure falls below charge pressure.
Different pressure relief settings may be used at each system port. The order code specifies HPRV pressure setting availability.
A HPRV valve with an orifice is available as an option. In some applications, it is desirable to use a HPRV/ Check with an orifice to allow for easier neutral adjustment. The orifice connects the working loop to the charge gallery. It allows a small amount of loop leakage which expands the dead band around the neutral position of the swashplate. Most applications find it suitable to configure only one side of the system loop with an orificed HPRV. An orifice referenced to the high pressure side of the loop will decrease effective efficiency of the system and increase heat into the system. By locating an orifice only on the reverse drive side of the loop, system efficiency losses are minimized. Increased downhill creep may also be present.
The HPRV are set at the following flow rates
Check/HPRV without orifice |
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5 l/min [1.3 US gal/min] |
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Check/HPRV with orifice |
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17 l/min [4.5 US gal/min] |
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P400026
C Caution
HPRV´s are factory set at a low flow condition. Any application or operating condition which leads to elevated HPRV flow will cause a pressure rise above the factory setting. Contact your Danfoss representative for an application review. Using an HPRV with an orifice may increase downhill creep.
W Warning
Unintended vehicle or machine movement hazard.
The vehicle must include a braking system redundant to the hydrostatic transmission, sufficient to stop and hold the vehicle or machine in the event of hydrostatic drive power loss.
10 | © Danfoss | February 2022 |
BC152886484876en-000309 |
Technical Information
DDC Axial Piston Pumps Size 20/24
Operation
In some applications it is desirable to bypass the hydraulic fluid around the pump so the machine/load can be moved without rotating the pump shaft or prime mover. An optional bypass valve mechanically connects both A & B sides of the system pressure together. The bypass is fully opened when the valve is turned (opened) counterclockwise 3 revolutions. The valve must be fully closed for normal operation.
Refer to the DDC pump outline drawings for location of the bypass valve.
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Bypass Valve |
System Loop (High Pressure) |
System Loop (Low Pressure) |
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P400027 |
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Bypass valve wrench size and torque |
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Wrench size |
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Torque N•m [lbf•ft] |
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17 mm external |
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12.0 [9.0] |
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C Caution
Excessive speed or extended movement will damage the pump and motor(s)
Avoid excessive speeds and extended load/vehicle movement when using the bypass function. Damage to the drive motor is possible if the load or vehicle is moved at a speed greater than 20% of maximum or for a duration exceeding 3 minutes..
© Danfoss | February 2022 |
BC152886484876en-000309 | 11 |
Technical Information
DDC Axial Piston Pumps Size 20/24
Operation
An internal charge pressure relief valve (CPRV) regulates charge pressure within the hydraulic circuit. The CPRV is a direct acting poppet valve that regulates charge pressure at a designated level above case pressure.
The charge pressure relief valve setting is specified within the model code of the pump. DDC pumps with charge pump have the CPRV set at 1800 rpm while DDC pumps without charge pump have the CPRV set with below external charge supply.
Charge pressure setting in MMC [bar] |
External charge flow [L/min] |
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7 |
8.6 |
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11, 14, 18, 21 |
13.5 |
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The 7 bar charge pressure rise rate, with flow, is approximately 0.8 bar/10 liter [4.4 psi/US gal].
The 11 and 14 bar charge pressure rise rate, with flow, is approximately 1.4 bar /10 liter [7.7 psi/US gal].
The 18 and 21 bar charge pressure rise rate, with flow, is approximately 1.6 bar/10 liter [8.8 psi/US gal] .
Case Drain
Charge Pressure |
P400028 |
C Caution
When a DDC pump is used with a variable motor, ensure the available charge pressure matches the required motor shift pressure. Contact your Danfoss representative for the availability of additional charge relief settings.
12 | © Danfoss | February 2022 |
BC152886484876en-000309 |
Technical Information
DDC Axial Piston Pumps Size 20/24
Operation
DDC pumps are available with an optional integral loop flushing. A loop flushing valve will remove heat and contaminants from the main loop at a rate faster than otherwise possible.
The DDC loop flushing design is a simple spring centered shuttle spool with an orifice plug. The shuttle shifts at approximately 8 bar [115 psi]. The flushing flow is a function of the low loop system pressure (charge) and the size of the plug.
Notched Diameter
Working Loop (Low Pressure) |
Case |
Working Loop (High Pressure) |
P400029
Loop flushing valve is not available with charge pump combination.
Loop flushing performance
Oil Temp = 50°C (~30 mm2/S) |
<![if ! IE]> <![endif]>Flow [lpm] |
Charge pressure [d bar] |
P400301 |
When a DDC pump is used with an external loop flushing shuttle valve, ensure that the charge setting of the pump matches the setting of the loop flushing shuttle valve. Contact your Danfoss representative for the availability of additional charge relief settings.
© Danfoss | February 2022 |
BC152886484876en-000309 | 13 |
Technical Information
DDC Axial Piston Pumps Size 20/24
Operation
The DDC pump features direct displacement control (DDC) .The swashplate angle is set directly by a linkage attached to the swashplate trunnion. Moving the control lever changes the displacement and direction of flow.
The input shaft is configurable to the left or right side of the pump.
All DDC pumps will transfer hydraulic forces from within the transmission into the pump control arm where these forces are seen as a control arm torque. The nature and magnitude of the control arm torque is a function of transmission operating conditions (pump speed, pressure and displacement) and design of the DDC valve plate. During normal operation the control arm torque will be stroke reducing, whereas dynamic braking and downhill operation likely will result in stroke increasing control arm feedback. The driver and/or the mechanical linkage must be able to return the pump to neutral under all conditions. Contact Danfoss for additional application support regarding lower control arm torque options.
Maximum allowable control arm torque, applied from the customer linkage, is 79.1 Nm (700 in-lbs). Linkage stops may be required to limit input torque to the control arm. Maximum swashplate angle is +/- 18 degrees.
DDC Pumps Control Moment
Input=2000 rpm, Temp=50°C, Shell Tellus 46 Viscosity=30m 2/s Stroking Speed=1deg/sec, Standard HPRV
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<pumping mode> |
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<b> |
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Stroke decreasingmoment |
50 |
Stroke increasingmoment |
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40 |
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b |
6 bar |
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30 |
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35 bar |
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50 bar |
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<![if ! IE]> <![endif]>(N•m) |
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20 |
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100 bar |
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200 bar |
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<![if ! IE]> <![endif]>moment |
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10 |
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300 bar |
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0 |
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-20 |
-15 |
-10 |
-5 |
0 |
5 |
10 |
15 |
20 |
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<![if ! IE]> <![endif]>Trunnion |
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-10 |
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-20 |
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-30 |
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-40 |
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Stroke increasingmoment |
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-50 |
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Stroke decreasingmoment |
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Angle (deg) |
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P400030 |
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14 | © Danfoss | February 2022 |
BC152886484876en-000309 |
Technical Information
DDC Axial Piston Pumps Size 20/24
This section defines the operating parameters and limitations with regard to input speeds and pressures.
Minimum speed is the lowest input speed recommended during engine idle condition. Operating below minimum speed limits pump’s ability to maintain adequate flow for lubrication and power transmission.
Rated speed is the highest input speed recommended at full power condition. Operating at or below this speed should yield satisfactory product life.
Maximum speed is the highest operating speed permitted. Exceeding maximum speed reduces product life and can cause loss of hydrostatic power and braking capacity. Never exceed the maximum speed limit under any operating conditions.
Operating conditions between Rated speed and Maximum speed should be restricted to less than full power and to limited periods of time. For most drive systems, maximum unit speed occurs during downhill braking or negative power conditions.
During hydraulic braking and downhill conditions, the prime mover must be capable of providing sufficient braking torque in order to avoid pump over speed. This is especially important to consider for turbocharged and Tier 4 engines.
W Warning
Unintended vehicle or machine movement hazard.
Exceeding maximum speed may cause a loss of hydrostatic drive line power and braking capacity. You must provide a braking system, redundant to the hydrostatic transmission, sufficient to stop and hold the vehicle or machine in the event of hydrostatic drive power loss.
System pressure is the differential pressure between system ports A and B. It is the dominant operating variable affecting hydraulic unit life. High system pressure, which results from high load, reduces expected life. Hydraulic unit life depends on the speed and normal operating, or weighted average, pressure that can only be determined from a duty cycle analysis.
Application pressure is the high pressure relief setting normally defined within the order code of the pump. This is the applied system pressure at which the driveline generates the maximum calculated pull or torque in the application.
Maximum working pressure is the highest recommended Application pressure. Maximum working pressure is not intended to be a continuous pressure. Propel systems with Application pressures at, or below, this pressure should yield satisfactory unit life given proper component sizing.
Maximum pressure is the highest allowable Application pressure under any circumstance. Application pressures above Maximum Working Pressure will only be considered with duty cycle analysis and factory approval. Pressure spikes are normal and must be considered when reviewing maximum working pressure.
All pressure limits are differential pressures referenced to low loop (charge) pressure. Subtract low loop pressure from gauge readings to compute the differential.
Minimum low loop pressure (above case pressure) is the lowest pressure allowed to maintain a safe working condition in the low side of the loop.
An internal charge relief valve regulates charge pressure. Charge pressure maintains a minimum pressure in the low side of the transmission loop.
The charge pressure setting listed in the order code is the set pressure of the charge relief valve with the pump in neutral, operating at 1800 min-1 [rpm], and with a fluid viscosity of 32 mm2/s [150 SUS]. Pumps
© Danfoss | February 2022 |
BC152886484876en-000309 | 15 |
Technical Information
DDC Axial Piston Pumps Size 20/24
Operating Parameters
configured with no charge pump (external charge supply) are set with a charge flow of 18.9 l/min [5.0 US gal/min] and a fluid viscosity of 32 mm2/s [150 SUS].
The charge pressure setting is referenced to case pressure.
At normal operating temperature charge inlet pressure must not fall below rated charge inlet pressure (vacuum).
Minimum charge inlet pressure is only allowed at cold start conditions. In some applications it is recommended to warm up the fluid (e.g. in the tank) before starting the engine and then run the engine at limited speed until the fluid warms up.
Maximum charge pump inlet pressure may be applied continuously.
Under normal operating conditions, the rated case pressure must not be exceeded. During cold start case pressure must be kept below maximum intermittent case pressure. Size drain plumbing accordingly.
C Caution
Possible component damage or leakage
Operation with case pressure in excess of stated limits may damage seals, gaskets, and/or housings, causing external leakage. Performance may also be affected since charge and system pressure are additive to case pressure.
The high temperature limits apply at the hottest point in the transmission, which is normally the motor case drain. The system should generally be run at or below the rated temperature.
The maximum intermittent temperature is based on material properties and should never be exceeded.
Cold oil will not affect the durability of the transmission components, but it may affect the ability of oil to flow and transmit power; therefore temperatures should remain 16 °C [30 °F] above the pour point of the hydraulic fluid.
The minimum temperature relates to the physical properties of component materials. Size heat exchangers to keep the fluid within these limits. Danfoss recommends testing to verify that these temperature limits are not exceeded.
Ensure fluid temperature and viscosity limits are concurrently satisfied.
Viscosity For maximum efficiency and bearing life, ensure the fluid viscosity remains in the recommended range.
The minimum viscosity should be encountered only during brief occasions of maximum ambient temperature and severe duty cycle operation.
The maximum viscosity should be encountered only at cold start.
16 | © Danfoss | February 2022 |
BC152886484876en-000309 |