BENTLY 135473-01 – Proximitor Sensor Probe for Vibration Monitoring

Product Description

The BENTLY 135473-01 is a eddy current proximity probe that forms the front-end sensing element in Bently Nevada’s machinery monitoring systems. This probe operates on the principle of eddy current generation, where a high-frequency signal energizes a coil in the probe tip, creating an electromagnetic field. When a conductive target (typically the rotating shaft) approaches the probe tip, eddy currents are generated in the target surface, altering the impedance of the probe coil and producing a voltage signal proportional to the gap between probe and target.

The BENTLY 135473-01 features a rugged, hermetically sealed construction designed for harsh industrial environments. The probe tip contains the sensing coil encapsulated in a durable material resistant to oil, water, and most industrial contaminants. The probe body is constructed from stainless steel, providing mechanical strength and corrosion resistance. The integral coaxial cable is specially shielded to maintain signal integrity over distances up to several meters.

This probe operates in conjunction with a Bently Nevada Proximitor driver, which provides the oscillator/demodulator function, converting the probe impedance change into a DC voltage proportional to gap (for position measurement) and an AC voltage proportional to vibration (for dynamic measurement). The combined probe and driver system provides two critical measurements from a single sensor: static gap (position) and dynamic motion (vibration).

The BENTLY 135473-01 is available in various lengths and thread configurations to accommodate different machine configurations and mounting requirements. The probe tip diameter, typically 5mm, 8mm, or 11mm, determines the linear range and sensitivity of the measurement. The 135473-01 model represents a specific configuration within Bently Nevada’s extensive probe family, with characteristics optimized for common turbomachinery applications.

Calibrated for specific target materials (typically steel alloys), the BENTLY 135473-01 provides linear output over its measurement range, enabling precise determination of shaft position and accurate measurement of vibration amplitudes. The system’s frequency response extends from DC to over 10 kHz, capturing both slow position changes and high-frequency vibration components essential for comprehensive machinery condition assessment.

Parameters and Specifications

Advantages and Features

The BENTLY 135473-01 offers numerous benefits that make it the preferred choice for critical machinery vibration monitoring:

Key Advantages

• Non-Contact Measurement: The eddy current principle enables measurement without physical contact with the rotating shaft, eliminating wear and allowing operation at any rotational speed, from zero to maximum.

• Dual Measurement Capability: A single BENTLY 135473-01 probe provides both static (position) and dynamic (vibration) information, enabling comprehensive assessment of shaft condition and behavior.

• Insensitive to Contaminants: The eddy current principle is unaffected by oil, water, steam, or process fluids in the gap between probe and target, ensuring reliable operation in lubricated environments.

• Wide Frequency Response: DC to 10 kHz response captures both slow thermal growth and high-frequency vibration components, essential for complete machinery analysis.

• Rugged Construction: Hermetically sealed, stainless steel construction with high-temperature capability ensures reliable operation in harsh turbine and compressor environments.

• High Accuracy: Precision calibration provides linear output with high sensitivity, enabling accurate measurement of small vibration amplitudes and precise position determination.

• Long-Term Stability: The passive sensing element exhibits no drift over time, ensuring consistent measurements throughout the probe’s operational life.

• Hazardous Area Suitability: Versions with appropriate approvals can be installed in explosive atmospheres, common in oil and gas applications.

• Bently Nevada Integration: Seamless compatibility with Bently Nevada’s 3300 and 3500 monitoring systems ensures proper signal conditioning and integration with protection and diagnostic software.

• Field-Proven Reliability: With decades of service in thousands of critical machines worldwide, the BENTLY 135473-01 has demonstrated exceptional reliability in the most demanding applications.

• Interchangeability: Standardized mounting threads and electrical characteristics allow replacement with minimal system reconfiguration.

Application Fields and Cases

The BENTLY 135473-01 is essential for vibration and position monitoring across various critical rotating machinery applications:

Primary Application Areas

1. Power Generation:

   • Gas turbine generators (radial vibration and thrust position)

   • Steam turbine generators (journal bearings and thrust bearings)

   • Hydroelectric turbines (guide bearings)

   • Generator exciters and collector rings

2. Oil and Gas:

   • Centrifugal compressors (pipeline and process)

   • Gas turbine-driven compressors

   • Pumps (especially high-speed or critical service)

   • Expanders and turboexpanders

3. Industrial:

   • Large electric motors (above 1000 HP)

   • Gearboxes (high-speed shafts)

   • Fans and blowers (critical service)

   • Paper machine rolls

4. Marine:

   • Main propulsion turbines

   • Ship service generators

   • Compressors on LNG carriers

Application Case Examples

• Combined Cycle Power Plant: A 600 MW combined cycle facility utilizes BENTLY 135473-01 probes on all gas turbine and steam turbine journal bearings and thrust bearings. During a startup following maintenance, one probe detected an abnormal vibration signature that analysis revealed as a rotor bow condition. The early warning allowed operators to shut down and investigate before damage occurred, avoiding a potential catastrophic failure and extended outage.

• Gas Pipeline Compressor Station: A major pipeline operator employs BENTLY 135473-01 probes on centrifugal compressors across multiple stations. The probes’ immunity to oil and process gas contamination ensures reliable operation in the challenging environment. When a compressor began showing increasing synchronous vibration, analysis of probe data identified the onset of rotor imbalance, enabling planned maintenance during a scheduled outage rather than an emergency shutdown.

• Refinery Critical Pump: A refinery’s hydrocracker unit depends on a high-speed pump monitored by BENTLY 135473-01 probes. When the pump experienced a sudden vibration increase, the monitoring system triggered an alarm, allowing operators to switch to the standby pump before failure. Subsequent inspection revealed bearing damage that would have caused catastrophic failure within hours. The probe’s early warning prevented a unit shutdown costing millions in lost production.

• Hydroelectric Plant: A large hydroelectric facility installed BENTLY 135473-01 probes on turbine guide bearings during a modernization project. The ability to measure both shaft position and vibration from a single probe simplified installation and reduced wiring requirements. The position measurement capability proved valuable for monitoring bearing wear over time, enabling predictive maintenance scheduling.

Comparison with Competitors

When compared to similar proximity probes from other manufacturers, the BENTLY 135473-01 demonstrates several distinctive characteristics:

Comparative Advantages

• Installed Base Leadership: The BENTLY 135473-01 benefits from the largest installed base of any proximity probe in critical turbomachinery, providing unparalleled field experience and proven reliability.

• Bently System Integration: As the original Bently Nevada probe, the BENTLY 135473-01 offers seamless integration with the full range of Bently monitoring systems, including 3300, 3500, and System 1 software.

• Application Expertise: Bently Nevada’s decades of focus on machinery monitoring translate into probes optimized for the specific requirements of turbomachinery applications.

• Interchangeability Standards: Bently probes have established de facto industry standards for mounting threads and electrical characteristics, simplifying replacement and sparing.

• Comprehensive Support: Backed by Baker Hughes’ global service network, users of BENTLY 135473-01 probes have access to extensive technical support and application engineering.

Selection Suggestions and Precautions

Selection Criteria

When considering the BENTLY 135473-01 for your application, evaluate the following factors:

1. System Compatibility: Verify that the probe is compatible with your Bently Nevada monitoring system (3300, 3500, etc.). The BENTLY 135473-01 requires matching Proximitor drivers for proper operation.

2. Measurement Requirements: Determine the required measurement range, sensitivity, and frequency response for your application. Different tip diameters provide different linear ranges and sensitivities.

3. Physical Installation: Assess the available mounting space, required probe length, and thread type (imperial or metric) needed for your machine. The BENTLY 135473-01 is available in various configurations.

4. Target Material: Verify that the probe calibration matches your shaft material. Bently probes are typically calibrated for AISI 4140 steel; other materials may require recalibration or correction factors.

5. Environmental Conditions: Ensure the probe temperature rating meets your application requirements. Standard probes handle -35°C to +177°C; high-temperature versions are available for extreme conditions.

6. Hazardous Area Requirements: If installing in classified areas, verify that the BENTLY 135473-01 variant has the required certifications (CSA, ATEX, IECEx) for your location.

7. Cable Length: Determine the required cable length to reach the Proximitor driver location. Excess cable can be coiled, but proper practices must be followed.

8. Spare Parts Strategy: For critical machines, maintain spare BENTLY 135473-01 probes to minimize downtime in case of damage during maintenance or unexpected failure.

Installation Precautions

• Handling Sensitivity: The probe tip and cable are sensitive to damage. Handle with care, avoiding sharp bends in the cable and impacts to the probe tip.

• Mounting Preparation: Ensure the mounting hole is clean, properly tapped, and deburred before installation. Debris in the threads can damage the probe or affect measurements.

• Installation Torque: Follow Bently’s recommended installation torque to avoid damaging the probe or affecting its characteristics. Over-torquing can damage the probe tip.

• Gap Setting: Proper initial gap is critical for measurement range. Follow manufacturer recommendations for cold gap setting based on expected thermal growth.

• Cable Routing: Route probe cables away from high-voltage sources and avoid running parallel to power cables. Maintain minimum bend radius specifications.

• Cable Securing: Secure the probe cable at regular intervals to prevent vibration-induced movement and connector stress. Use appropriate cable ties and clamps.

• Connector Protection: Ensure connectors are properly protected from moisture and contamination. Use approved sealing methods for hazardous area installations.

• Target Condition: The target surface (shaft) must be clean and free of scratches, pits, or magnetic inconsistencies that could affect measurements.

• Electrical Runout Check: Before final acceptance, perform an electrical runout check to verify that shaft surface variations do not produce false vibration signals.

• Documentation: Record probe installation details including serial numbers, initial gap readings, and cable routing for future reference.

Commissioning and Maintenance

• Initial Verification: After installation, verify probe operation by measuring gap voltage at the Proximitor output and comparing to expected values.

• System Calibration: Confirm that the monitoring system configuration matches the probe characteristics (sensitivity, range, etc.).

• Baseline Recording: Record baseline vibration and position readings for future comparison during trend analysis.

• Periodic Checks: During routine maintenance, inspect probe cables for damage, verify connector integrity, and check gap readings if machine has been reassembled.

• Replacement Precautions: When replacing a probe, verify that the new unit has identical characteristics and is properly configured in the monitoring system.

Conclusion

The BENTLY 135473-01 represents the industry standard for eddy current proximity probing in critical rotating machinery monitoring applications. Its robust construction, proven reliability, and seamless integration with Bently Nevada monitoring systems make it the preferred choice for protecting valuable turbomachinery assets in power generation, oil and gas, and industrial applications worldwide.

By providing both static position and dynamic vibration information from a single sensor, the BENTLY 135473-01 enables comprehensive condition monitoring essential for predictive maintenance, machinery protection, and failure analysis. The probe’s immunity to contaminants, wide frequency response, and long-term stability ensure reliable measurements in the most demanding environments.

For facilities with Bently Nevada monitoring systems, maintaining an appropriate inventory of BENTLY 135473-01 probes represents a prudent risk management strategy. These sensors are often the first line of defense against machinery failure, and their availability when needed is critical for minimizing downtime.

As industrial facilities face increasing demands for reliability and asset utilization, the BENTLY 135473-01 provides the accurate, reliable measurement foundation for effective machinery condition monitoring programs. By choosing genuine Bently Nevada components, you ensure compatibility, performance, and access to the application expertise essential for protecting critical rotating equipment.

For purchasing or additional technical information about the BENTLY 135473-01, please visit: BENTLY 135473-01 Product Page