External gear pump High Performance AZPF

Description

• Platform F
• Fixed displacement
• Size 4 … 28
• Continuous pressure up to 250 bar
• Intermittent pressure up to 280 bar

Features

• Consistent high quality based on large-volume production
• Long service life
• Slide bearings for high loads
• Drive shafts according to ISO or SAE and customer-specific solutions
• Line ports: connection flange or screw thread
• Combination of several pumps possible

Product description

General information

It is the central task of external gear pumps to convert mechanical energy (torque and speed) into hydraulic energy (flow and pressure). To reduce heat losses, Rexroth’s external gear units offer very high efficiencies. They are realized by pressure-dependent gap sealing and highly precise production technology.

Rexroth external gear pumps are built in four frame sizes: Platform B, F, N and G. Within each platform different sizes can be realized by different gear widths. The pumps are available in the versions Standard, High-Performance, SILENCE und SILENCE PLUS. Further configuration variants are given by different flanges, shafts, valve arrangements and multiple pump combinations.

Pumping principle

Due to the teeth moving apart during the rotation from the tooth mesh, the gear chambers become clear. The resulting negative pressure as well as the atmospheric pressure on the hydraulic fluid level in the reservoir cause hydraulic fluid to flow from the reservoir to the pump. This hydraulic fluid fills the gear chambers and is transported in them in the direction of the arrow (see sectional drawing) along the housing from the suction side to the pressure side. The teeth mesh again then, force the hydraulic fluid out of the gear chambers and prevent it from flowing back to the suction chamber.

Construction

The external gear pump consists essentially of a pair of gear wheels supported in bearing bushings and the housing with a front cover and an end cover.

The drive shaft protrudes from the front cover where it is usually sealed by the shaft seal. The bearing forces are absorbed by slide bearings. These bearings were designed for high pressures and have excellent emergency running properties, especially at low rotational speeds.

The gear wheels have 12 teeth. This keeps both flow pulsation and noise emission to a minimum. The sealing of the pressure chambers is achieved by forces depending on the working pressure. This ensures optimum efficiency. The working pressure generated in the gear chambers is transferred to the outside of the bearing bushings in specifically designed pressure fields in such a way that they are pressed against the gears and seal them up. The pressurized compression areas are limited by special seals. The seal in the area between the gear teeth and the housing is ensured by the smallest of gaps that are set depending on the pressure between the gear teeth and housing.

External gear pump layout

Gear pumps with integrated valves

In order to reduce piping complexity, a flow control valve or pressure-relief valve can be integrated in the cover of the gear pump. Such solutions are used, for instance, for the hydraulic oil supply of power steering systems. The pump delivers a constant flow or maximum

pressure irrespective of the rotational speed. The residual flow distributed externally to other consumers.

Pressure relief valve, external pressure discharge

p1 = 5 to 250 bar

Pressure relief valve, pressure discharge into suction line

p1 = 5 to 250 bar

3-way flow control valve, residual flow distributed externally, loadable

qconst = 2 to 30 l/min

3-way flow control valve, residual flow returned in suction line

qconst = 2 to 30 l/min

3-way flow control valve with pressure relief valve, residual flow returned in suction line

qconst = 2 to 30 l/min; p1 = 100 to 180 bar

Type code

Type code single pump

Note

• Not all of the variants according to the type code are possible.

• Please select the desired pump with the help of the selection table (preferred types ) or after consultation with Bosch Rexroth.

• Special options are available on request.

Type code multiple pump

Note

• Not all of the variants according to the type code are possible.

• Please select the desired pump with the help of the selection table (preferred types ) or after consultation with Bosch Rexroth.

• Special options are available on request.

Example 4-way pump:

AZPG…032… + AZPG…022… + AZPJ…016… + AZPJ…012…

Technical data

Table of values

General technical data

Corrosion protection

Note

• Safety requirements pertaining to the whole systems are to be observed.

• Please contact us for applications with frequent load changes.

Pressure definition

Determining the operating characteristics
Flow		[l/min]
Torque		[Nm]
Power		[kW]

Note

You can find diagrams for a rough calculation in chapter "Diagrams / Characteristic curves".

Hydraulic fluids

The external gear unit is designed for operation with HLP mineral oil according to DIN 51524, 1-3. Under higher load, however, Bosch Rexroth recommends at least HLP compliant with DIN 51524 Part 2.

See the following data sheet for application instructions and requirements for selecting hydraulic fluid, behavior during operation as well as disposal and environmental protection before you begin project planning:

• 90220: Hydraulic fluids based on mineral oils and related hydrocarbons

Other hydraulic fluids on request.

Selection of hydraulic fluid

Bosch Rexroth evaluates hydraulic fluids on the basis of the Fluid Rating according to the technical data sheet 90235.

Hydraulic fluids with positive evaluation in the Fluid Rating are provided in the following technical data sheet:

• 90245: Bosch Rexroth Fluid Rating List for Rexroth hydraulic components (pumps and motors)

The hydraulic fluid should be selected so that the operating viscosity in the operating temperature range is within the optimum range (νopt; see selection diagram).

Viscosity and temperature of hydraulic fluids

Observe the instructions for the filtration of the hydraulic fluid (see chapter Project planning information).

Direction of rotation

The dimensional drawings in the chapter Dimensions represent pumps for clockwise rotation. The position of the drive shaft or the position of suction and pressure port changes for counter-clockwise rotation.

Direction of rotation, viewed on drive shaft

Drives

1. Elastic couplings

• The coupling must not transfer any radial and axial forces onto the pump.

• The maximum admissible radial run-out deviation from the shaft to the fitting slot is 0.2 mm.

• Admissible shaft shifting see installation information of the coupling manufacturers.

2. Coupling sleeve

• To be used on splined shaft profile according to DIN and SAE.

• Attention: No radial or axial forces are permitted on the pump shaft or coupling sleeve. The coupling sleeve must be free to move axially.

• The distance between the pump drive shaft and drive shaft on the customer side must 2+1 mm.

• Provide installation space for the snap ring.

• Oil-bath or oil-mist lubrication is required.

3. Tang drive coupling

• For attaching the pump directly to an electric motor or combustion engine, gear, etc.

• The pump shaft has a special tang drive and driver (3) (scope of delivery see offer drawing)

• There is no shaft sealing

• Drive-side installation and sealing according to the following recommendations and dimensions

• Drive shaft on the customer side (1)
  • Case-hardening steel DIN EN 10084 e.g. 20MnCrS5 case-hardened 0.6 mm deep; HRC 60±3
  • Seal ring running surface ground without rifling Rt ≤ 4 μm

• Radial shaft seals on the customer side (2)
  • Provide with rubber cover (see DIN 3760, type AS or double-lipped ring)
  • Provide installation edge with 15° slant or install shaft seal with protection sleeve

AZPF-1x

AZPF-2x

4. V-belts and straight gear wheels or helical toothed gear drives without outrigger bearing

For V-belt or gear wheel drives, please contact us specifying the application and mounting conditions (dimensions a, dm, dw and angle α). For helical toothed gear drives, details of the helix angle β are also required.

5. Outrigger bearing

Outrigger bearing are offered to eliminate possible problems when the pumps are driven by V-belts or gear wheels. The diagrams show the radial and axial load capacity in relation to a bearing service life of LH = 1000 h.

Front cover A (type 1)

Front cover G (type 2)

Maximum transferable drive torques

Splined shafts

Tapered shafts

Parallel keyed shafts

Tang drive

With outrigger bearing

Multiple gear pumps

Gear pumps are well-suited to multiple arrangements, whereby the drive shaft of the first pump stage is extended to a second and possibly third pump stage. The shaft of the individual pump sections are normally connected via a driver or via a splined coupling (reinforced

through drive).

The individual pump stages are usually hydraulically isolated and have separate suction ports. On request a common suction port or separated but hydraulically connected suction ports are available.

For the configuration of multiple pumps, Bosch Rexroth recommends arranging the pump stage with the largest displacement on the drive side.

Note

Basically, the parameters of the single pumps apply, however certain restrictions need to be observed:

• Maximum rotational speed: This is determined by the largest pump stage used.

• Pressures: These are restricted by the maximum transmissible torques of the drive shaft, the through drive and the driver.

Addition of drive torques

Please note, that in multiple pump arrangements the drive torques of the single pumps stages will add up according to the following formula:

This may result in pressure restrictions for the respective pump stages.

Standard through drive (tang drive coupling)

In the case of AZPF pumps the driver for the following pump stage can carry a load of up to Mmax = 65 Nm (AZPF-1x) resp. Mmax = 85 Nm (AZPF-2x).

Please note possibly resulting pressure restrictions for the following pump stages. Subsequent pumps of a smaller series determine the max. transmissible torque.

Reinforced through drives

For applications with higher transfer torques or torsional vibrations reinforced through drives up to Mmax = 160 Nm are available. Lay out design on request.

Diagrams/characteristic curves

Flow characteristic curves

Note

• Characteristic curves measured at ν = 32 mm²/s and t = 50 °C.

Power diagrams

Size 4

Size 5

Size 8

Size 11

Size 14

Size 16

Size 19

Size 22

Size 25

Size 28

Noise charts

Noise levels dependent on the rotational speed, pressure range between 10 bar and pressure value p2 (see chapter "Technical data").

These are typical characteristic values for the respective size. They describe the airborne sound emitted solely by the pump.

Ambient influences (installation site, piping, other system components) were not taken into account.

The values refer to one individual pump.

Note

• Characteristic curves measured at ν = 32 mm²/s and t = 50 °C.

• Sound pressure level calculated from noise measurements made in the low reflection measuring room according to DIN 45635, Part 26.

• Distance from measuring sensor to pump: 1 m.

Size 4

Size 5

Size 8

Size 11

Size 14

Size 16

Size 19

Size 22

Size 25

Size 28

Dimensions

Drive shafts

Tapered shaft 1:5

(for front cover B, P, N)

Tapered shaft 1:5

(for outrigger bearing A, G)

Tapered shaft 1:8

Splined shaft (SAE J744 16-4 9T)

Splined shaft (SAE J744 19-4 11T)

Splined shaft (DIN 5482 B17 x 14)

Tang drive

Parallel keyed shaft (SAE J744 16-1 A)

Parallel keyed shaft (ISO ⌀18 mm)

Front cover

Rectangular flange ⌀80 mm

Rectangular flange ⌀36.47mm

2-bolt flange ⌀82.55 mm, SAE J744 82-2 (A)

2-bolt flange ⌀101.6mm, SAE J744 101-2 (B)

2-bolt mounting ⌀52mm, with O-ring

2-bolt mounting ⌀52mm, compressor port

2-bolt mounting ⌀50mm, connection variant 1

2-bolt mounting ⌀50 mm, connection variant 2

4-bolt mounting ⌀52 mm, with O-ring

Outrigger bearing ⌀80 mm, type 1

Outrigger bearing ⌀80 mm, type 2

Line connections

Pipe thread according to ISO 228-1

Metric threads according to ISO 6149, O-ring

UN-thread according to ISO 11926-1 / ASME B 1.1, O-ring

Note

Depending on the design variant, the size of the threaded connections may differ from the sizes specified in the table.

See information in the dimensional drawings.

Square flange

Square flange

Preferred program

Tapered shaft 1:5 with rectangular flange ⌀80 mm

AZPF – 1X – … CB20MB

Splined shaft (DIN 5482 B17 x 14) with rectangular flange ⌀80 mm

AZPF – 1X – … FB20MB

Tapered shaft 1:8 with rectangular flange ⌀36.47 mm

AZPF – 12 – … HO30KB

Splined shaft (DIN 5482 B17 x 14) with rectangular flange ⌀36.47 mm

AZPF – 1X – … FO30MB

Tapered shaft 1:8 with rectangular flange ⌀36.47 mm

AZPF – 1X – … HO01MB

Parallel keyed shaft (ISO ⌀18) with rectangular flange ⌀80 mm

AZPF – 11 – … AB01MB – S0356

Tapered shaft 1:5 with 2-bolt mounting ⌀50 mm

AZPF – 1X – … CP20MB

Tapered shaft 1:5 with 2-bolt mounting ⌀50 mm

AZPF – 1X – … CN20MB

Splined shaft (DIN 5482 B17 x 14) with 2-bolt mounting ⌀50 mm

AZPF – 1X – … FN20MB

Splined shaft (DIN 5482 B17 x 14) with 2-bolt mounting ⌀50 mm

AZPF – 1X – … FP20PB

Tang drive with 4-bolt mounting ⌀52 mm

AZPF – XX – … NT20MB

Tang drive with 2-bolt mounting ⌀52 mm and O-ring (compressor port)

AZPF – 1X – … NL20KB

Parallel keyed shaft (SAE J744 16-1 A) with 2-bolt flange ⌀82.55 mm, SAE J744 82-2 (A)

AZPF – 1X – … QR12MB

Splined shaft (SAE J744 16-4 9T) with 2-bolt flange ⌀82.55 mm, SAE J744 82-2 (A)

AZPF – 1X – … RR12MB

Splined shaft (SAE J744 16-4 9T) with 2-bolt flange ⌀82.55 mm, SAE J744 82-2 (A)

AZPF – 1X – … RR20MB

Splined shaft (SAE J744 19-4 11T) with 2-bolt flange ⌀82.55 mm, SAE J744 82-2 (A)

AZPF – 2X – … PR20KB

Parallel keyed shaft (SAE J744 16-1 A) with 2-bolt flange ⌀82.55 mm, SAE J744 82-2 (A)

AZPF – 1X – … QR20MB

Tapered shaft 1:5 with outrigger bearing ⌀80 mm, type 1

AZPF – 11 – … SA20MB

Tapered shaft 1:5 with outrigger bearing ⌀80 mm, type 2

AZPF – 1X – … SG20MB

Tapered shaft 1:5 with 2-bolt mounting ⌀50 mm

AZPFF – 12 – … CP2020KB

Splined shaft (DIN 5482 B17 x 14) with rectangular flange ⌀80 mm

AZPFF – 1X – … FB2020MB

Tapered shaft 1:5 with rectangular flange ⌀80 mm

AZPFF – 1X – … CB2020MB

Tapered shaft 1:8 with rectangular flange ⌀36.47 mm

AZPFF – 1X – … HO2020MB

Splined shaft (SAE J744 16-4 9T) with 2-bolt flange ⌀82.55 mm, SAE J744 82-2 (A)

AZPFF – 1X – … RR2020MB

Tang drive with 2-bolt mounting ⌀52 mm and O-ring

AZPFF – 1X – … NM2020MB

Splined shaft (DIN 5482 B17 x 14) with 2-bolt mounting ⌀50 mm

AZPFF – 1X – … FP2020MB

Tapered shaft 1:5 with outrigger bearing ⌀80 mm, type 1

AZPFF – 1X – … SA2020MB

Tapered shaft 1:5 with outrigger bearing ⌀80 mm, type 2

AZPFF – 1X – … SG2020PB

Tang drive with 2-bolt mounting ⌀52 mm and O-ring

AZPFF – 1X – … NL2020KB

Splined shaft (DIN 5482 B17 x 14) with rectangular flange ⌀80 mm

AZPFFF – 1X – … FB202020MB