Start-Up Procedure; Preconditions For Trouble-Free Operation - Sauer Danfoss 20 Series Service Manual

PRECONDITIONS FOR
TROUBLE-FREE
OPERATION
Series 20 – Axial Piston Pumps
Service Manual and Repair Instructions

Start-up procedure

Cleanliness: Ensure that the pipes, pipe connections and hoses as well as all other
components are completely clean.
Ventilation and venting of the oil reservoir via an air filter.
Operating fluid: HLP fluid according to DIN 51524, ATF type A SUFFIX A, HD-SAE motor
oils, see Fluid Manufacturers,Technical Information.
Oil level: (The inlet pipe and return flow port must always be below the surface of the
oil). No funnel-shaped eddying at the inlet connection pipe. No formation of foam at
the return flow pipe.The inlet connection pipe must be substantially above the bottom
of the reservoir. A partition plate should be located between the inlet and return flow
connection pipes.
Filtration: Filtration grade = 10 µm [394 µinch] nominal.
Inlet pressure of charge pump: 0.85 bar [12.3 psi] absolute (- 0.15 bar [-2.2 psi]) with a
new filter element and at an operating temperature of approx. 50 °C [122 °F].
A charge pump inlet pressure less than 0.75 bar [10.9 psi] absolute (-0.25 bar [-3.6 psi]) is
permissible for a short time with a reservoir temperature of less than 50 °C [122 °F] on a
cold start in order to warm up the system under no-load.
If frequent cold starts are to be made, the system should be warmed up by a reservoir
heater.
If the charge pump inlet pressure is less than 0.75 bar [10.9 psi] absolute (-0.25 bar [-3.6
psi]) on operating temperatures higher than 50 °C [122 °F], the filters must be changed.
A charge pump inlet pressure of less than 0.5 bar [7.3 psi] absolute (- 0.5 bar [-7.3 psi])
is not permissible.
The filter requires changing or the operating temperature is too low.
Venting the pump and motor housing as well as the connection lines and other
components.
The return flow to the oil reservoir must be free of bubbles. After venting the system,
check the fluid level and fill to proper level if necessary.
Carry out a leak test on the transmission (inlet line, filter, pipe and hose lines, valves,
control elements, pump and motor) giving due consideration to the service life of the
transmission, environmental protection and the reduction of oil consumption.
Tighten up any leaking joints and other connections while the system is not under
pressure.
Pressure fluid temperature range: min. = -40 °C [-40 °F], max. = 95 °C [203 °F].
Viscosity range:
max. = 1000 mm /s [4630 SUS*] (cSt) (for a short time only on a cold start).
2
min. = 7 mm /s [49 SUS*] (cSt).
2
Recommended viscosity range: 12-60 mm
*SUS (Saybolt Universal Second)
Changing the oil: The oil should be changed after max. 80-100 hours of operation, but at
the latest one year after first-time operation.
The second oil change should be after max. 500 hours of operation but at the latest one
year after the first change of fluid.
Thereafter, the oil should be changed every 1000 hours of operation but at least once a
year. It is not permissible to mix oil.
Renew the inlet filter each time the oil is changed or when the inlet pressure of the
charge pump falls below the permissible tolerance.
Clean the air filter whenever too much dirt has accumulated.
The max. speed is as specified in the catalogue Series 20 Axial Piston Pumps,Technical
Information or Series 20 Axial Piston Motors,Technical Information.
DKMH.PS.315.B1.02 520L0535
/s [66-278 SUS*] (cSt).
2
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