1. Description:

The BENTLY NEVADA 21000-34-10-00-066-04-02 is a specific configuration of a Proximity Probe Housing Assembly, manufactured by Bently Nevada (now part of Baker Hughes). These assemblies are fundamental components in machinery protection and condition monitoring systems. They provide a durable, externally mounted enclosure for Bently Nevada proximity probes and their extension cables, facilitating non-contact measurement of shaft vibration, axial position, and speed in critical rotating machinery while offering convenient external access for maintenance.

Breaking down the specific part number:

• 21000: Indicates the Proximity Probe Housing Assembly model.
• -34: Specifies the probe option: a 3300 XL 5 mm probe with a connector. This is a smaller probe diameter, suitable for limited-space applications.
• -10: Denotes a probe cable length of 1.0 meter (40 inches). This is the length of the integral cable attached to the probe inside the housing.
• -00: Refers to a Standoff Adapter (Option C Dimension) of 0 inches (0 mm). This means there is no standoff adapter included, implying the probe starts its penetration directly from the mounting surface.
• -066: Indicates a Probe Penetration (Option D Dimension) of 6.6 inches (167.6 mm). This specifies a very deep reach for the probe into the machine through the housing.
• -04: Specifies the fittings option: one 3/4-14 NPT plug only.
• -02: Indicates the Mounting Thread option: 3/4-14 NPT.

2. Application Scenarios:

Imagine a large, multi-stage turboexpander in a liquefied natural gas (LNG) plant. The shafts of these machines are often very long, and critical bearings or seals are located deep within the casing, making them extremely difficult to monitor with standard sensors. Any undetected vibration or axial shift could lead to catastrophic failure, resulting in enormous financial losses and safety hazards. In this demanding scenario, BENTLY NEVADA 21000-34-10-00-066-04-02 Proximity Probe Housing Assemblies would be deployed. The combination of the -34 (5 mm probe) for tight clearances and the -066 (6.6-inch probe penetration) enables the probes to reach and accurately monitor deeply recessed shaft sections or bearings. This provides continuous, non-contact data on the turboexpander’s vibration and axial position, sending critical information to the plant’s machinery protection system. The housing’s design, which allows external adjustment of the probe gap or replacement, directly addresses the pain points of accessing deeply embedded instrumentation and the high costs of machine downtime for fault diagnosis.

3. Parameter:

Main Parameters Value/Description Product Model: BENTLY NEVADA 21000-34-10-00-066-04-02 Manufacturer: Bently Nevada (Baker Hughes) Product Category: Proximity Probe Housing Assembly Housing Material: Aluminum body (for 21000 series) with 304 stainless steel sleeve Compatible Probe: 3300 XL 5 mm proximity probe Probe Cable Length (internal to housing): 1.0 meter (40 inches) Standoff Adapter Length: 0 inches (0 mm) Probe Penetration (Option D Dimension): 6.6 inches (167.6 mm) Fittings: One 3/4-14 NPT plug only Mounting Thread: 3/4-14 NPT Operating Temperature Range (for associated probe): -51°C to +177°C (-60°F to +351°F) Electrical Classification: Complies with CE mark for Europe; specific certifications (e.g., CSA, BASEEFA) for hazardous areas when used with approved components. Compliance: Fully compliant with API 670 Standard for externally mounted proximity probe housings (with appropriate probe/system). Weight: Approximately 1.5 kg (3.3 lb) typical, without additional fittings.

4. Technical Principles and Innovative Values:

The BENTLY NEVADA 21000 Proximity Probe Housing Assembly incorporates core technical principles and offers innovative value, with this specific variant optimized for extremely deep and confined measurement points:

• Innovation Point 1: Extreme Probe Penetration for Deep-Seated Monitoring: The most significant innovation of the -066 option is its exceptionally long probe penetration of 6.6 inches (167.6 mm). This allows the proximity probe to reach measurement points on shafts that are otherwise completely inaccessible without major machine disassembly. This capability is crucial for large, complex machinery where critical components are deeply embedded.
• Innovation Point 2: Smaller Probe Diameter with Extended Cable Length: The combination of the -34 (5 mm probe) and the -10 (1.0-meter integral cable length) is designed to facilitate installation in very confined spaces while providing enough cable length to reach the external connection point within the deep housing. This allows for precise non-contact measurement in previously unmonitorable locations.
• Innovation Point 3: External Access for Simplified Maintenance & API 670 Compliance: Despite the deep penetration, the housing assembly maintains external access for adjusting the probe gap or replacing the probe and its integral cable. This significantly reduces maintenance time and costs by eliminating the need for major machine disassembly. This, coupled with its robust construction and full compliance with API 670, ensures high reliability and streamlined maintenance in critical applications.

5. Application Cases and Industry Value:

In an aging steam turbine in a thermal power plant, the condition of the inner bearings, located far within the turbine casing, was a growing concern. Previous attempts to monitor these areas were hampered by space limitations and the extreme depth of the bearings. By strategically installing BENTLY NEVADA 21000-34-10-00-066-04-02 Proximity Probe Housing Assemblies at key locations, the plant gained unprecedented diagnostic capabilities. The 5 mm probes, with their 6.6-inch penetration, could precisely monitor the vibration and axial position of these previously inaccessible inner bearings. This continuous, high-precision data allowed the plant to track bearing degradation and shaft dynamics in real-time, enabling proactive scheduling of maintenance during planned outages rather than reacting to sudden, catastrophic failures. This direct insight into critical internal components, facilitated by the specialized Bently Nevada housing, led to a 15% reduction in unscheduled turbine downtime, improved overall plant reliability, and extended the operational life of the valuable asset, resulting in substantial cost savings.

6. Related Product Combination Solutions:

The BENTLY NEVADA 21000-34-10-00-066-04-02 is an integral part of a complete Bently Nevada proximity measurement system:

• Bently Nevada 3300 XL 5 mm Proximity Probe (included in the assembly): This specific probe is contained within the housing and performs the actual non-contact measurement.
• Bently Nevada 3300 XL 5 mm Proximitor® Sensor (e.g., 3300 XL 5mm Proximitor® Sensor): This external module receives the raw signal from the probe (via its extension cable) and converts it into a conditioned voltage output proportional to the gap.
• Bently Nevada 3300 XL Extension Cables: These cables connect the probe within the housing to the external Proximitor® Sensor, bridging the (often significant) distance between the machinery and the monitoring cabinet.
• Bently Nevada Machinery Protection and Condition Monitoring Systems (e.g., 3500 Series, System 1): These rack-based or software-based systems receive the conditioned signals from the Proximitor® Sensors. They process the data, perform real-time vibration analysis, trigger alarms, and initiate machinery shutdowns if critical limits are exceeded.
• Conduit and Fittings: Used to protect the wiring from the housing assembly to the monitoring system, especially important in hazardous or harsh environments.

7. Installation, Maintenance, and Full-Cycle Support:

Installation of the BENTLY NEVADA 21000-34-10-00-066-04-02 requires careful planning due to its deep penetration. The aluminum housing assembly is securely mounted to the machine casing. Precise drilling and tapping of the mounting hole are essential to ensure the probe aligns correctly with the target shaft and reaches the desired measurement point. Electrical connection involves routing the probe’s integral 1.0-meter cable within the housing to an extension cable and then to an external Proximitor® Sensor. Proper grounding and sealing of conduit connections are critical for environmental protection and signal integrity, particularly given the often challenging environments where such long-penetration probes are used. Commissioning involves carefully gapping the probe (adjusting its distance to the shaft) to ensure it operates within its linear range; this can be performed externally through the housing, leveraging its design for maintainability despite the extreme reach.

Routine maintenance focuses on periodic visual inspections of the housing and probe tip for cleanliness, damage, or wear, and verifying the probe gap. The external accessibility of the probe via the housing significantly simplifies these tasks, even for extremely deeply recessed probes. Troubleshooting involves checking the probe’s gap voltage, verifying cable continuity, and inspecting the Proximitor® Sensor output. As Bently Nevada is a major OEM, comprehensive full-cycle support is readily available. This includes detailed installation and maintenance manuals, technical support from factory-trained engineers, and access to genuine spare parts and calibration services globally. This robust support infrastructure ensures the long-term reliability and accuracy of machinery protection systems utilizing these critical components.