Fixed Displacement Bent Axis Piston Motor AA2FM

Ordering code for standard program

Hydraulic fluid

Axial piston unit

Drive shaft bearing

Operation mode

Size

Series

Index

Direction of rotation

Seals

Drive shafts

Mounting flange

•=Available         ○=On request          －= Not available

Port plates for service lines

Speed sensors

Special version

Standard / special version

•=Available        ○=On request        -=Not available       ▲=Not for new projects

1.Fastening threads or threaded ports are SAE (UN/UNF)

2.Threaded ports at the sides (sizes 10 to 63) plugged with threaded plugs

3.Note the restrictions on page 32

4.Please contact us.

5.Fastening threads and threaded ports are metric

6.Specify ordering code of counterbalance valve according to data sheet (BVD－RE 95522,BVE－RE 95525) separately.

7.Specify ordering code of sensor according to data sheet(DSM－RE 95132, DSA－RE 95133, HDD－RE 95135) separately and observe the requirements on the electronics

Technical data

Hydraulic fluid

 Before starting project planning, please refer to our data sheets RE 90220 (mineral oil), RE 90221 (environmentally acceptable hydraulic fluids), RE 90222 (HFD hydraulic fluids)and RE 90223 (HFA, HFB, HFC hydraulic fluids) for detailed information regarding the choice of hydraulic fluid and application conditions.

The fixed motor AA2FM is not suitable for operation with HFA hydraulic fluid. If HFB, HFC or HFD or environmentally acceptable hydraulic fluids are used, the limitations regarding technical data or other seals must be observed.

Selection diagram

Viscosity and temperature of hydraulic fluid

Details regarding the choice of hydraulic fluid

The correct choice of hydraulic fluid requires knowledge of the operating temperature in relation to the ambient temperature: in a closed circuit, the circuit temperature, in an open circuit, the reservoir temperature.

The hydraulic fluid should be chosen so that the operating viscosity in the operating temperature range is within the optimum range (ν_opt see shaded area of the selection diagram).We recommended that the higher viscosity class be selected in each case.

Example: At an ambient temperature of X℉ (X℃), an opera-ting temperature of 140℉(60℃) is set in the circuit. In the optimum operating viscosity range (ν_opt, shaded area), this corresponds to the viscosity classes VG 46 or VG 68; to be selected: VG 68.

Note

The case drain temperature, which is affected by pressure and speed, can be higher than the circuit temperature or reservoir temperature. At no point of the component may the temperature be higher than 240℉ (115℃). The temperature difference specified below is to be taken into account when determining the viscosity in the bearing.

If the above conditions cannot be maintained due to extreme operating parameters, we recommend flushing the case at port U (size 250) or using a flushing and boost pressure valve

Filtration of the hydraulic fluid

Finer filtration improves the cleanliness level of the hydraulic fluid, which increases the service life of the axial piston unit.

To ensure the functional reliability of the axial piston unit, a gravimetric analysis of the hydraulic fluid is necessary to determine the amount of solid contaminant and to determine the cleanliness level according to ISO 4406. A cleanliness level of at least 20/18/15 is to be maintained.

At very high hydraulic fluid temperatures (+195℉ to +240℉ (90℃ to maximum 115℃)), a cleanliness level of at least19/17/14 according to ISO 4406 is necessary.

If the above classes cannot be achieved, please contact us.

Shaft seal

Permissible pressure loading

The service life of the shaft seal is influenced by the speed of the axial piston unit and the case drain pressure (case pressure). The mean differential pressure of 30 psi (2 bar) between the case and the ambient pressure may not be enduringly exceeded at normal operating temperature. For a higher differential pressure at reduced speed, see diagram. Momentary pressure spikes (t <0.1 s) of up to 145 psi (10 bar) are permitted. The service life of the shaft seal decreases with an increase in the frequency of pressure spikes.

The case pressure must be equal to or higher than the ambient pressure.

The values are valid for an ambient pressure

P_abs = 15 psi (1 bar).

Temperature range

The FKM shaft seal may be used for case drain temperaturesfrom-13℉ to +240℉ (-25℃ to +115℃).

Note

 For application cases below -13℉ (-25℃), an NBR shaft seal is required (permissible temperature range: -40℉ to 195℉(-40℃ to +90℃). State NBR shaft seal in plain text when ordering.

Please contact us.

Direction of flow

Speed range

No limit to minimum speed n_min. If uniformity of motion is required, speed n_min must not be less than 50 rpm. See table of values on page 7 for maximum speed.

Long-life bearing

Size 250

For long service life and use with HF hydraulic fluids. Identical external dimensions as motor with standard bearings. Subsequent conversion to long-life bearings is possible. Bearing and case flushing via port U is recommended.

Flushing flow (recommended)

Operating pressure range

(operating with mineral oil)

Pressure at service line port A or B

Sizes 10 to 180

Nominal pressure p_nom______________5800 psi (400 bar) absolute

Maximum pressure p_max______________6500 psi (450 bar) absolute

Single operating period__________________10s

Total operating period___________________300h

Summation pressure (pressure A + pressure B)p_Su_____________10150 psi (700 bar)

Sizes 250

Nominal pressure p_nom____________5100 psi (350 bar) absolute

Maximum pressure p_max____________5800 psi (400 bar) absolute

Single operating period__________________10s

Total operating period__________________300h

Summation pressure (pressure A + pressure B) psu___________10150 psi (700 bar)

 Minimum pressure (high-pressure side)___________________365 psi (25 bar) absolute

Rate of pressure change R_A max

with integrated pressure-relief valve___________130000 psi/s (9000 bar/s)

without pressure-relief valve______________232000 psi/s (16000 bar/s)

Note

Values for other hydraulic fluids, please contact us.

Minimum pressure - pump mode (inlet)

To prevent damage to the axial piston motor in pump operating mode (change of high-pressure side with unchanged direction of rotation, e.g. when braking), a minimum pressure must be guaranteed at the service line port (inlet). The minimum pressure depends on the speed of the axial piston unit (see characteristic curve below).

This diagram is valid only for the optimum viscosity range from ν_opt = 170 to 74 SUS (36 to 16 mm²/s).

Please contact us if these conditions cannot be satisfied.

Definition

Nominal pressure P_nom

The nominal pressure corresponds to the maximum design pressure.

 Maximum pressure P_max

The maximum pressure corresponds to the maximum operating pressure within the single operating period. The sum of the single operating periods must not exceed the total operating period.

Minimum pressure (high-pressure side)

Minimum pressure at the high-pressure side (A or B) which is required in order to prevent damage to the axial piston unit.

 Summation pressure p_Su

The summation pressure is the sum of the pressures at both service line ports (A and B).

Rate of pressure change R_A

Maximum permissible rate of pressure rise and reduction during a pressure change over the entire pressure range.

Total operating period = t₁ +t₂+... +t_n

 Table of values (theoretical values, without efficiency and tolerances; values rounded)

1)The values are valid:

- for the optimum viscosity range from

ν_opt = 170 to 74 SUS (36 to 16 mm²/s)

- with hydraulic fluid based on mineral oils

2)Intermittent maximum speed: overspeed for unload and overhauling processes, t <5 s and Δp <2200 psi (150 bar)

3) Restriction of input flow with counterbalance valve, see page 32

4) Torque without radial force, with radial force see page 9

Note

Operation above the maximum values or below the minimum values may result in a loss of function, a reduced service life or in the destruction of the axial piston unit. Other permissible limit values, with respect to speed variation, reduced angular acceleration as a function of the frequency and the permissible start up angular acceleration (lower than the maximum angular acceleration) can be found in data sheet RE 90261.

Determining the operating characteristics

V_g = Displacement per revolution in in³ (cm³)
Δp = Differential pressure in psi (bar)
n = Speed in rpm
η_v= Volumetric efficiency
η_mh = Mechanical-hydraulic efficiency
η_t = Total efficiency (η_t=η_t∙η_mn)

Effect of radial force F_q on the service life of bearings

 By selecting a suitable direction of radial force F_q, the load on the bearings, caused by the internal rotary group forces can be reduced, thus optimizing the service life of the bearings. Recommended position of mating gear is dependent on direction of rotation. Examples:

Permissible radial and axial forces of the drive shafts(splined shaft and parallel keyed shaft)

Size		NG		10	10	10	12	12	12	163)	16
Drive shaft		Φ	in	7/8	0.79	0.98	7/8	0.79	0.98	7/8	0.98
			mm	－	20	25	－	20	25	－	25
Maximum radial force1) at distance a (from shaft collar)		Fq max	lbf	629.5	674.4	719.4	741.9	674.4	719.4	966.7	719.4
			kN	2.8	3.0	3.2	3.3	3.0	3.2	4.3	3.2
		a	in	0.63	0.63	0.63	0.63	0.63	0.63	0.63	0.63
			mm	16.8	16	16	16.8	16	16	16.8	16
with permissible torque		Tmax	lb-ft	47.9	49	47.9	56.1	56.1	56.9	72.3	73.8
			Nm	65	66	65	76	76	76	98	100
≜ permissible pressure Δp		Δp perm	psi	5800	5800	5800	5800	5800	5800	5550	5800
			bar	400	400	400	400	400	400	385	400
Maximum axial force2)		-Fax max	lbf	71.9	71.9	71.9	71.9	71.9	71.9	71.9	71.9
			N	320	320	320	320	320	320	320	320
		+Fax max	N	0	0	0	0	0	0	0	0
Permissible axial force per psi (bar) operating pressure		±Fax perm/bar	lbf/psi	0.05	0.05	0.05	0.05	0.05	0.05	0.05	0.05
			N/bar	3.0	3.0	3.0	3.0	3.0	3.0	3.0	3.0

Size		NG		23	23	23	28	28	28	32	32
Drive shaft		Φ	in	1  1/4	0.98	1.18	1  1/4	0.98	1.18	1  1/4	1.18
			mm	－	25	30	－	25	30	－	30
Maximum radial force1) at distance a (from shaft collar)		Fq max	lbf	809.3	1281.4	1213.9	989.1	1281.4	1213.9	1146.5	1213.9
			kN	3.6	5.7	5.4	4.4	5.7	5.4	5.1	5.4
		a	in	0.94	0.63	0.63	0.94	0.63	0.63	0.94	0.63
			mm	24	16	16	24	16	16	24	16
with permissible torque		Tmax	lb-ft	106.2	108	106.2	131.3	132	131.3	150.5	150.5
			Nm	144	146	144	178	179	178	204	204
≜ permissible pressure Δp		Δp perm	psi	5800	5800	5800	5800	5800	5800	5800	5800
			bar	400	400	400	400	400	400	400	400
Maximum axial force2)		-Fax max	lbf	112.2	112.2	112.2	112.2	112.2	112.2	112.2	112.2
			N	500	500	500	500	500	500	500	500
		+Fax max	N	0	0	0	0	0	0	0	0
Permissible axial force per psi (bar) operating pressure		±Fax perm/bar	lbf/psi	0.08	0.08	0.08	0.08	0.08	0.08	0.08	0.08
			N/bar	5.2	5.2	5.2	5.2	5.2	5.2	5.2	5.2

1) With intermittent operation

2) Maximum permissible axial force during standstill or when the axial piston unit is operating in non-pressurized condition.

3) Restricted technical data

Note

Influence of the direction of the permissible axial force:

+F_ax max=Increase in service life of bearings

-F_ax max=Reduction in service life of bearings (avoid)

Size		NG		45	45	563)	56	56	56	633)	63	63
Drive shaft		Φ	in	1  1/4	1.18	1  1/4	1  3/8	1.18	1.37	1  1/4	1  3/8	1.38
			mm	－	30	－	－	30	35	－	－	35
Maximum radial force1) at distance a (from shaft collar)		Fq max	lbf	1641	1709	1709	2068	2136	2045	1708	2315	2046
			kN	7.3	7.6	7.6	9.2	9.5	9.1	7.6	10.3	9.1
		a	in	0.94	0.71	0.94	0.94	0.71	0.71	0.94	0.94	0.71
			mm	24	18	24	24	18	18	24	24	18
with permissible torque		Tmax	lb-ft	214	214	223	263	263	263	223	295	295
			Nm	290	290	302	356	357	356	302	400	400
≜ permissible pressure Δp		Δp perm	psi	5800	5800	4950	5800	5800	5800	4350	5800	5800
			bar	400	400	339	400	400	400	301	400	400
Maximum axial force2)		-Fax max	lbf	142	142	180	180	180	180	180	180	180
			N	630	630	800	800	800	800	800	800	800
		+Fax max	N	0	0	0	0	0	0	0	0	0
Permissible axial force per psi (bar) operating pressure		±Fax perm/bar	lbf/psi	0.11	0.11	0.13	0.13	0.13	0.13	0.13	0.13	0.13
			N/bar	7.0	7.0	8.7	8.7	8.7	8.7	8.7	8.7	8.7

Size		NG		803)	803）	80	80	903)	903	90	1073)	107
Drive shaft		Φ	in	1  1/4	1  3/8	1.37	1.57	1  1/4	1  3/8	1.57	1  1/2	1  3/4
			mm	－	－	35	40	－	－	40	－	－
Maximum radial force1) at distance a (from shaft collar)		Fq max	lbf	1709	2608	2608	2563	1709	2608	2563	2788	2743
			kN	7.6	11.6	11.6	11.4	7.6	11.6	11.4	12.4	12.2
		a	in	0.94	0.94	0.79	0,79	0.94	0.94	0.79	1.06	1.32
			mm	24	24	20	20	24	24	20	27	33.5
with permissible torque		Tmax	lb-ft	223	332	378	378	223	332	423	438	502
			Nm	302	450	512	512	302	450	573	594	680
≜ permissible pressure Δp		Δp perm	psi	3450	5100	5800	5800	3050	4550	5800	5100	5800
			bar	237	352	400	400	211	314	400	349	400
Maximum axial force2)		-Fax max	lbf	225	225	225	225	225	225	225	281	281
			N	1000	1000	1000	1000	1000	1000	1000	1250	1250
		+Fax max	N	0	0	0	0	0	0	0	0	0
Permissible axial force per psi (bar) operating pressure		±Fax perm/bar	lbf/psi	0.16	0.16	0.16	0.16	0.16	0.16	0.16	0.20	0.20
			N/bar	10.6	10.6	10.6	10.6	10.6	10.6	10.6	12.9	12.9

1.With intermittent operation

2.Maximum permissible axial force during standstill or when theaxial piston unit is operating in non-pressurized condition.

3.Restricted technical data

Note

Influence of the direction of the permissible axial force:

+F_{ax max}=Increase in service life of bearings

-F_{ax max}=Reduction in service life of bearings (avoid)

Size		NG		107	107	1253)	125	125	1603)	160	160	1803)	180
Drive shaft		Φ	in	1.57	1.77	1  1/2	1  3/4	1.77	1  3/4	1.77	1.97	1  3/4	1.97
			mm	40	45	－	－	45	－	45	50	－	50
Maximum radial force1) at distance a (from shaft collar)		Fq max	lbf	3057	3169	2788	3215	3170	3350	4069	4114	3350	4114
			kN	13.6	14.1	12.4	14.3	14.1	14.9	18.1	18.3	14.9	18.3
		a	in	0.79	0.79	1.06	1.32	0.79	1.32	0.98	0.98	1.32	0.98
			mm	20	20	27	33.5	20	33.5	25	25	33.5	25
with permissible torque		Tmax	lb-ft	501	502	438	587	587	611	753	749	611	844
			Nm	679	680	594	796	796	828	1021	1016	828	1144
≜ permissible pressure Δp		Δp perm	psi	5800	5800	4350	5800	5800	4700	5800	5800	4200	5800
			bar	400	400	298	400	400	325	400	400	289	400
Maximum axial force2)		-Fax max	lbf	281	281	281	281	281	360	360	360	360	360
			N	1250	1250	1250	1250	1250	1600	1600	1600	1600	1600
		+Fax max	N	0	0	0	0	0	0	0	0	0	0
Permissible axial force per psi (bar) operating pressure		±Fax perm/bar	lbf/psi	0.20	0.20	0.20	0.20	0.20	0.26	0.26	0.26	0.26	0.26
			N/bar	12.9	12.9	12.9	12.9	12.9	16.7	16.7	16.7	16.7	16.7

Size		NG		250
Drive shaft		Φ	in	1.97
			mm	50
Maximum radial force1) at distance a (from shaft collar)		Fq max	lbf	2705)
			kN	1.25)
		a	in	1.61
			mm	41
with permissible torque		Tmax	lb-ft	1027
			Nm	1393
≜ permissible pressure Δp		Δp perm	psi	5100
			bar	350
Maximum axial force2)		-Fax max	lbf	450
			N	2000
		+Fax max	N	0
Permissible axial force per psi (bar) operating pressure		±Fax perm/bar	lbf/psi	4)
			N/bar

1)With intermittent operation

2)Maximum permissible axial force during standstill or when theaxial piston unit is operating in non-pressurized condition.

3) Restricted technical data

4) Please contact us.

5) When at a standstill or when axial piston unit operating in non-pressurized conditions. Higher forces are permissible when under pressure, please contact us.

Note

Influence of the direction of the permissible axial force:

+F_{ax max} = Increase in service life of bearings

-F_ax max = Reduction in service life of bearings (avoid)