Description
Reliable mechanical shielding and environmental protection for critical machinery protection transducers are delivered by the Bently Nevada 21000-28-05-00-074-04-02 proximity probe housing assembly. Designed for seamless integration into severe industrial operating environments, this heavy-duty enclosure protects proximity probes from physical impacts, process contaminants, and hazardous atmosphere exposure, ensuring continuous, high-accuracy vibration and position measurements on high-speed rotating assets.
Key Features
-
3300 XL Compatibility: Optimized with Option 28 to house a 3300 XL 8 mm proximity probe with multiple hazardous area approvals.
-
Corrosion-Resistant Housing: Constructed with a durable aluminum body and a high-strength 304 stainless steel sleeve for harsh industrial exposures.
-
Pre-configured Probe Cable Length: Features option 05 for routing a 0.5-meter (20-inch) probe cable securely.
-
Explosion-Proof Integrity: Maintains robust environmental sealing and physical containment in critical locations.
-
Precise Sleeve Penetration: Engineered for a fixed 7.4-inch probe penetration depth without a standoff adapter.
Applications
- Continuous radial vibration and axial position monitoring in steam and gas turbines.
- Casing protection and probe placement on heavy-duty centrifugal and axial compressors.
- Industrial gearbox, generator, and large electric motor bearing housing protection.
- Hostile petrochemical, oil and gas, and power generation environments requiring hazardous area certifications.
Technical Specifications
| Parameter |
Specification |
| Manufacturer |
Bently Nevada |
| Part Number |
21000-28-05-00-074-04-02 |
| Product Type |
Proximity Probe Housing Assembly |
| Probe Option |
3300 XL 8 mm probe with multiple approvals (28) |
| Probe Cable Length |
0.5 meter (20 inches) (05) |
| Standoff Adapter Length |
No standoff adapter (00) |
| Probe Penetration Depth |
7.4 inches (188 mm) (074) |
| Fittings Option |
One 3/4-14 NPT plug only (04) |
| Mounting Thread Option |
3/4-14 NPT (02) |
| Housing Material |
Aluminum body |
| Sleeve Material |
304 Stainless Steel |
| Shipping Weight (Calculated) |
2.0 kg (4.4 lbs) |
Empirical Engineering Insights
Alternative Models & Compatibility
This proximity probe housing assembly can be directly replaced by the newer configuration code 21000-16-05-00-074-04-02. When executing a migration or swap to the replacement assembly, verify that the hazardous area certifications of the internal 16-option probe fully align with the regional classifications of your operating site.
Application Pitfalls & Engineering Notes
Thermal expansion deltas between the aluminum housing body and the 304 stainless steel sleeve must be factored in when mounting to high-temperature turbine casings. Always ensure that the NPT mounting threads are treated with a high-temperature, anti-seize compound to prevent galling during future disassembly or recalibration procedures.
Commissioning & Wiring Tips
When routing the 0.5-meter coaxial probe cable through the conduit outlet, maintain the minimum specified bend radius of 25.4 mm (1.0 inch) for Bently Nevada coaxial cables. Sharp bends or pinch points inside the housing body can alter the electrical properties of the cable, resulting in signal noise or incorrect calibration slopes at the Proximitor sensor.
Installation Guidelines
CRITICAL WARNING
Before installing or opening this housing assembly, ensure the monitored industrial asset is fully de-energized and locked out. Verify that the localized environment is non-hazardous and free of explosive gas mixtures before removing any housing covers or NPT plugs.
1
Apply an approved thread sealant to the 3/4-14 NPT mounting threads of the sleeve before inserting the unit into the machine port.
2
Carefully guide the sleeve into the tapped installation port, avoiding any lateral impact on the proximity probe tip.
3
Thread the housing assembly into the casing until tight, then align the conduit outlets to facilitate efficient cable routing.
4
Secure the 3/4-14 NPT plug in the unused conduit port to preserve the explosion-proof rating of the enclosure.