The Bently Nevada 31000-00-00-00-120-00-02 serves as the primary 31000 Proximity Probe Housing Assembly utilized to execute physical containment and environmental shielding of proximity sensors across TSI (Turbine Supervisory Instrumentation) platforms.

Part Number Code Selection

The mechanical structure and configuration profile of this housing are detailed by the following individual option codes:

• 31000: Base model designation for standard English Proximity Probe Housing Assemblies.
• -00: Indicates that no proximity probe is pre-installed in this assembly.
• -00: Indicates that no integrated probe cable is pre-installed.
• -00: Specifies that no standoff adapter is utilized.
• -120: Designates a probe penetration depth of 12.0 inches (304.8 mm).
• -00: Configured without pre-installed electrical conduit fittings.
• -02: Selects a main housing-to-casing mounting thread of 3/4-14 NPT.

Mechanical Construction Parameters

Eddy-Current Probe Integration and Calibration Guardrails

This empty housing assembly is optimized to receive and protect standard 3300 XL 8 mm or 7200 Series 8 mm eddy-current proximity probes. When a probe is installed, the housing sleeve permits external gap adjustments to achieve the target gap voltage validation of -10 VDC. Correct sleeve alignment prevents spatial drift, ensuring that rotor dynamics, axial thrust, and dynamic shaft vibration measurements remain highly linear and calibrated to standard AISI 4140 steel. Grounding paths integrated into the metallic sleeve suppress electromagnetic cross-talk between adjacent sensor channels.

Scope of Delivery

• 1 x Bently Nevada 31000-00-00-00-120-00-02 Housing Assembly (empty sleeve)
• 1 x Stainless steel internal sensor mounting bushing
• 2 x Hexagonal case locknuts

Mechanical Installation and Alignment Protocols

• Case Thread Tightening

  Verify that the machine case has a matching 3/4-14 NPT threaded port. Apply a high-temperature industrial thread sealant to the mounting threads, and torque the housing body until a tight metal-to-metal interference fit is achieved (minimum of 5 full threads engaged).

• Preventing Structural Vibration Scratches

  When deploying the assembly for radial vibration measurements, the machine casing must be securely coupled to the bearing housing. Lack of structural rigidity will induce housing resonance, distorting the probe's displacement reading.

• Sleeve Depth Calibration

  Adjust the penetration depth of the 304.8 mm stainless steel sleeve relative to the shaft before locking the compression collar. Ensure that the sleeve does not contact the rotating target when the machine shaft expands dynamically under thermal load.

• Conduit Grounding and Seals

  Since this model is supplied without fittings (Option 00), appropriate certified explosion-proof 3/4-14 NPT cable glands must be field-installed. Apply conduit seal fittings to prevent process oil and moisture from back-draining into the PPS electrical junction area.

Transducer System Technical FAQ

• Can this housing model be used directly without a proximity probe?

  The housing acts as an empty pressure boundary and physical sleeve. A separate 8 mm proximity probe must be purchased and threaded inside to perform measurements.

• What is the benefit of the polyphenylene sulfide (PPS) outer dome?

  PPS is an engineered polymer that provides excellent structural strength and corrosion resistance against aggressive industrial oils and ammonia environments.

• Does this housing assembly require a standoff adapter for the 12.0-inch penetration?

  No. This model is built with the -00 option, which specifies that no standoff adapter is used; the housing threads directly into the casing port.

• How do you perform gap voltage validation with this housing?

  Loosen the compression sleeve gland and slide the internally mounted probe axially while monitoring the output voltage until the -10 VDC baseline is reached.

• What is the operating temperature threshold of the housing assembly?

  The composite PPS housing dome and standard 304 stainless steel sleeve are rated to operate continuously in temperatures from -51 to +177 deg C.

• Does this housing model comply with international petroleum industry standards?

  Yes. The physical dimensions and external adjustment design conform fully with the American Petroleum Institute (API) 670 standard.

• How do you prevent signal cross-talk when installing adjacent probes in the same housing run?

  Ensure the outer braided shields of all probe extension cables are grounded at one end only, typically at the main monitor rack barrier terminal.

• Can a 3/4-14 NPT conduit plug be used directly in the unused ports of this housing?

  Yes, standard 3/4-14 NPT plugs must be installed in any unused housing entry ports to preserve environmental seals and hazardous area certifications.