The axial piston variable displacement pumps of the type V30 of Doffer extremely high function safety. Its remarkably low noise levels, the high-pressure rating (peak = 420 bar/perm. = 350 bar), optimized power-to-weight ratio, as well as the wide controller range, make it possible to employ it for most industrial and mobile applications. The variable displacement pumps work according to the swash plate principle: 9 pistons operate in rotating cylinder cavities where they fulfill one suction and one pressure stroke per rotation.

Opening and closing of the cylinder cavities are via openings in the control disc. The axial movement of the pistons is provided by an adjustable swashplate. The setting angle (0 - max) can be steplessly varied in proportion to the desired displacement/flow. The setting range can be mechanically limited by setting screws (with V and VH controller only fixed limitation is possible). The position of the swash plate can be controlled via a visual mechanical indicator.

The latest knowledge and experience with regard to noise reduction have been used in the development of this pump design. V30D is therefore rather quiet, even when taken to the limit. All components used in the V30D are manufactured from high-grade materials and machined with close tolerances.

The wide range of modular controllers along with a thru-shaft (option for mounting auxiliary pumps or a second V30D) opens up a wide range of application possibilities.

Therefore type V30D features a pump design, which ideally suits the special requirements of modern industrial and mobile hydraulic drive systems.

Outstanding design features:

- Low specific weight.

- Very fast response times due to low mass moment of inertia of the setting unit.

- Special swashplate bearing helps reduce noise.

- New design of the hydrostatically balanced steel slipper shoes running on a bronze plate improves the life of typical wearing parts.

- Valve plate made from steel provides high wear resistance. Carefully designed dampening slots result in exceptionally low noise levels.

- Large shaft bearings provide long life.

The most important advantages:

- Low noise level, whereby secondary measures to reduce noise often are not necessary.

- Controller assemblies have been designed on a modular basis and can be installed without dismantling the basic pump.

- Thru- shaft allows tandem pump combinations and mounting of auxiliary pumps of all kinds (see sect. 5).

- Swashplate dial indicator provides a visual indication of displacement and can also be used to provide feedback information in control systems.

HAWE Variable displacement axial piston pump type V30D

Working principle	Variable displacement axial piston pump acc. to swash plate principle
Installation	Flange or brachet mounting
Direction of rotation	Right hand or left hand
Mounting position	Optional
Pressure fluid	Hydraulic fluid (DIN 51524 table 2 and 3); ISO VG 10 to 68 (DIN 51519)
	Viscosity range: min. 10; max. 1000 mm2/s,
	optimal operation range: 10...35 mm2/s
	Also suitable are biodegradable pressure fluids of the type HEES (synth. Ester) at operation
	temperatures up to +70°C
Temperatur	Ambient: -40 ... +60°C
	Fluid: -25...+80°C, pay attention to the viscosity range!
	Start temperature down to -40°C are allowable (Pay attention to the viscosity range during start
	long as the operation temperature during consequent running is at least 20K (Kelvin) higher
Filtration	Should conform to ISO standard 4406 coding 18/13.
Start-up	All hydraulic lines should be flushed with appropriate hydraulic fluid before start-up. The pump
	case should then be titled through the uppermost drain port. The drain line must be positioned
	so that the case is always filled during operation. At start-up and during the first few minutes
	of the operation the pressure relief valve should be adjusted to 50 bar (700 psi) or less.

Designation	45	75	95	115	140	160	250
Max. swash plate angle [°]	17	17.5	17	20	17.5	20	17.5
Min. inlet pressure (absolute), bar	0.85	0.85	0.85	0.85	0.85	0.85	0.85
open circuit (psi)	12	12	12	12	12	12	12
Self-priming speed at max rpm	2600	2400	2200	2000	2200	1900	1800
swash plate angle and 1 bar (15 psi )
absolute inlet pressure
Max. speed rpm	3600	3200	2900	2800	2600	2500	2000
(requires increased inlet pressure)	3600	3200	2900	2800	2600	2500	2000
Min. continuous speed rpm	500	500	500	500	500	500	500
Torque (theor.) at 1000 psi Nm	71	119	153	185	226	261	414
(Ibf ft)	35	61	78	93	115	132	203
Input power at 250 bar and 1450 rpm kW	30	50	64	77	95	109	174
at 3000 psiand 1800 rpm (hp)	41	68	87	105	129	148	237
Weight (approx. kg) without controller	40	60	70	70	85	85	130
(approx. lbs) without controller	88	132	154	154	187	187	287
(approx. kg) with controller	46	66	76	76	91	91	136
(approx. lbs) with controller	101	145	168	168	201	201	300
Moment of inertia kg m2	0.0056	0.0124	0.0216	0.0216	0.03	0.03	0.0825
(ft. Ibs. sec2)	0.0041	0.0092	0.016	0.016	0.022	0.022	0.061
L10 bearing life at 250bar (1450 rpm) (h)	31000	20000	17000	10000	17000	10000	23000
or 3600 psi (1800 rpm) and (h)	25000	16000	14000	8000	14000	8000	19000
max. displacement	25000	16000	14000	8000	14000	8000	19000

Max. dynamic torque
Spline shaft (D) input Nm	550	910	1200	1200	1700	1700	3100
(Ibf ft)	405	670	885	885	1250		2285
Spline shaft (D) output Nm	275	455	600	600	850	850	1550
(Ibf ft)	205	333	445	445	625		1145
Key shaft (K) input Nm	280	460	650	650	850	850	1550
(Ibf ft)	205	340	480	480	630	630	1145
Spline shaft (S) input Nm	500	501	1200	1200	1200	1200	1200
(Ibf ft)	370	370	885	885	885	885	885
Spline shaft (S) output 1) Nm	275	455	600	600	850	850	1000
(Ibf ft)	205	335	445	445	625	625	740
Noise level at 250 bar and (1450 rpm), (dB(A))	72	74	75	75	76	76	77
or 3600 psi and max. (1800 rpm) (dB(A))	75	78	79	79	80