Bently Nevada RK4 Specifications

RK4 Rotor Kit

Datasheet

Bently Nevada Machinery Condition Monitoring

Description

The RK 4 Rotor Kit closely simulates actual rotating machine
behavior. Its unique geometry and its ability for users to
isolate and control individual machine characteristics make it
useful as both a teaching aid and as a research and
development tool.

Machine malfunctions and experiments that can be
demonstrated include, but are not limited to:

l Rotor unbalance - both single plane and multiplane
l Shaft rub condition
l Oil whirl and oil whip instabilities

In addition to machinery behavior, the rotor kit can be used
to teach the fundamentals of proximity probe placement,
gapping, and troubleshooting. It can also help technicians
learn how to read and interpret proximity probe signals using
an oscilloscope.

141592 Rev. L

Performance and Features

The RK 4 Rotor Kit has a V-frame design that has been
developed to provide better control of the housing dynamic
stiffness properties. The mechanical tolerances have also
been tightened, resulting in more accurate machine behavior
modeling. The RK 4 Rotor Kit motor can closely hold the
desired speed with changes in loading conditions. This has
been accomplished by incorporating a direct current motor
and high performance control circuitry. The motor can run in
either a clockwise or counter-clockwise direction and has
adjustable slow roll speed capability. It can be controlled
remotely by using a ±5 volt control input, such as a signal
generator or dc power supply, to drive the motor speed
control device. Rotor speed is displayed on a digital
tachometer with a large LCD readout.

RK4 Rotor Kit
Datasheet 141592 Rev. L

The RK 4 Rotor Kit consists of:

l A mechanical base (including motor,

coupling, rotor shaft, two balance wheels,
two journal bearings and bearing blocks,
six proximity probes, three probe mounts,
a rub screw, and three safety covers).

l A Proximitor assembly that contains five

Proximitor units.

l A direct current motor speed control

device.

The motor speed control device provides power
for both the rotor kit and the Proximitor
assembly. A measurement and diagnostic
tool, such as an oscilloscope or other
diagnostic instrument, should be ordered
separately in order to observe the RK 4 machine
behavior.s

An optional Oil Whirl/Whip kit can be ordered.
The Oil whirl kit consists of:

l A high pressure oil pump assembly.
l An oil whirl bearing assembly.
l A rotor kit shaft with oil bearing journal.
l A load frame.

Fluid-induced instabilities (both oil whirl and
whip) as well as basic journal bearing behavior
can be demonstrated using the oil whirl/whip
kit. The oil whirl bearing is made from
transparent plastic, allowing the user to view
the oil film development during operation. The
load frame is used to remove the effect of
gravity on the rotor and to position the rotor to
any desired eccentricity ratio.

The kit includes:

l A mechanical base (including motor,

coupling, drive assembly, drive belts, and
two proximity probes for motor speed
control and Keyphasor signal pickup).

l A motor speed control unit.

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RK4 Rotor Kit
Datasheet 141592 Rev. L

Weight

Specifications

Basic Rotor Kit

Power 95 to 125 Vac, single phase,

or 190 to 250 Vac, single phase,
50 to 60 Hz at 3.0 A maximum.

Fuse Rating 250 V at 3 A slow-blow.

Buffered
Proximitor
Assembly
Outputs

Max Speed 10,000 rpm, typical.

Max Ramp
Rate

Mechanical Base Dimensions

Height 165 mm (6.5 in)

Width 340 mm (13.4 in)

Depth 789 mm (30.8 in)

Motor Speed Control Dimensions

Height 115 mm (4.5 in)

200 mV/mil.

±15,000 rpm/min. typical.

Rotor Kit
Base

Proximitor
Assembly

Motor Speed
Control

14.5 kg (32 lb)

0.9 kg (2 lb)

2.7 kg (6 lb)

Oil Whirl/Whip Kit

Oil Pump
Power

Oil Pump
Fuse Rating

Oil Pump Dimensions

Height 145 mm (5.7 in)

Width 317 mm (12.5 in)

Depth 292 mm (11.5 in)

95 to 125 Vac, single phase
50 to 60 Hz at 1.5 A maximum; or
190 to 250, single phase,
50 to 60 Hz at 0.75 A maximum.
User-selectable input voltage.

95 to 125 Vac
250 V 3.0 A slow-blow
190 to 250 Vac
250 V 1.5 A slow-blow
User-selectable fuse

Width 260 mm (10.3 in)

Depth 325 mm (12.8 in)

Proximitor Assembly Dimensions

Height 86 mm (3.4 in)

Width 154 mm (6.1 in)

Depth 158 mm (6.2 in)

Shaft
diameter

Environmental

Operating
Temperature

10 mm (0.4 in)

25° C ± 10° C (77° F ± 18° F)
95% RH Non-condensing
Recommended indoor use
only.

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RK4 Rotor Kit
Datasheet 141592 Rev. L

(16), 168614

Ordering Information

For the detailed listing of country and
product specific approvals, refer to the
Approvals Quick Reference Guide
(108M1756) available from
www.Bently.com.

(16) , and
105M7925
(4)

Spare Power Cords

 02198937 USA 10A/250V 3-wire

 285300 Brazil 10A/250V 3-wire

Rotor Kit

123456-AA

A: Oil Whirl/Whip Kit

0 0 Not required

0 1 Required

Accessories

Manuals

 126376 RK 4 Rotor Kit

 137482 Oil Whirl/Whip Kit

Safety Cover Replacement Parts (refer to
Figure 1)

 106M5920 Main Cover

 106M5918 Small End Cover

 106M5916 Speed Wheel Cover

Spare Probes

 330903­00-03-10­02-00

 330903­00-02-01­02-00

Additional Oil Whirl/Whip Option

 126379 Oil Whirl/Whip Kit

Spare 3300 NSv Probe, M8X1,
without armor
(Vibration, Keyphasor probes)

Spare 3300 NSv Probe, M8X1,
without armor
(Speed Probe)

 106M5917 End Cap Cover

(for use with fluid bearing only)

 105M7924,
105M7930,
106M8448,
and
106M8449

 105M7923
and
105M7929

 105M7931 Rubber Bumper

 04312254 Cover Hinge Set

Lock Mechanism

Polycarbonate Screw
(need quantity of 3 each)

(need quantity of 3)

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RK4 Rotor Kit
Datasheet 141592 Rev. L

Graphs and Figures

Figure 1: Rotor Kit

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RK4 Rotor Kit
Datasheet 141592 Rev. L

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notice or obligation. Contact your Baker Hughes representative for the most current information.

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

1631 Bently Parkway South, Minden, Nevada USA 89423

Phone: [phone] or 1.800.227.5514 (US only)

Bently.com

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