Bently Nevada 21000-28-05-00-076-04-02 21000 Proximity Probe Housing Assembly

Description

21000-28-05-00-076-04-02: 21000 Proximity Probe Housing Assembly with a 3300 XL 8 mm reverse-mount proximity probe with selectable hazardous area approvals (Option 28), 0.5 meter (20 in) probe cable (Option 05), zero standoff adapter length (Option 00), 7.6 in (193 mm) probe penetration (Option 076), one 3/4-14 NPT plug fitting (Option 04), and a 3/4-14 NPT mounting thread (Option 02).

This all-metal assembly is used for external mounting of proximity probes on rotating machinery. Compliant with the American Petroleum Institute (API) 670 Standard, it features an aluminum body with a 304 stainless steel sleeve. The sleeve houses and protects the reverse-mount probe, allowing external adjustments of the probe gap during machine operation. This variant uses a 0.5 meter cable and is supplied without a standoff adapter, achieving a direct sleeve penetration of 7.6 inches through the machine case. Port protection is managed via a single NPT plug, while the mounting thread is machined with approximately 5 to 7 full threads to increase connection stiffness and mechanical strength.

Features

• Option 28: Houses a 3300 XL 8 mm reverse-mount probe with multiple hazardous area approvals.
• Option 05: Equipped with a 0.5 meter (20 inches) probe cable.
• Option 00: Features no standoff adapter, mounting directly to the machine case.
• Option 076: Machined sleeve providing a probe penetration length of 7.6 inches (193 mm).
• Option 04: Supplied with one 3/4-14 NPT plug for unused conduit entries.
• Option 02: Standard 3/4-14 NPT mounting thread with 5 to 7 full threads for high connection stiffness.
• Aluminum housing body: Lightweight and resistant to corrosion in industrial environments.
• 304 stainless steel sleeve: Provides mechanical protection for the sensor probe tip and cable.
• API 670 compliance: Meets standard dimensions and sealing requirements for externally mounted proximity probe housings.

Applications

• Externally mounted vibration and position monitoring on steam turbines, gas turbines, and compressors.
• Shaft radial vibration, axial position, and speed measurements under API 670 specifications.
• Industrial environments requiring explosion-proof or flameproof housing protection for proximity sensors.
• Petrochemical plants, oil and gas refineries, and power generation facilities.

Ordering Information

Technical Specifications

Installation Guidelines

• Sleeve Support: Since the probe penetration length (Option D) is 7.6 inches (193 mm), additional sleeve support is not required by the 12-inch rule, but proper alignment within the mounting port must be maintained.
• Mounting Stiffness: Ensure the 3/4-14 NPT mounting thread (Option F: 02) is tightened securely. This machined thread provides approximately 5 to 7 full threads for high strength and connection stiffness.
• Probe Gapping: Adjust the probe gap externally by threading the assembly in or out of the case before final tightening. Refer to the 3300 XL 8 mm Transducer System User Guide for exact voltage-to-gap calibration details.
• Conduit Sealing: Use the supplied 3/4-14 NPT plug to seal unused conduit entries and maintain enclosure integrity against moisture and dirt ingress.
• Temperature Limit: Avoid exposing the internal probe to temperatures below -34 degC (-30 degF) to prevent damage to the probe pressure seals.

Compliance and Certifications

• RoHS: European Community Directive 2011/65/EU compliant.
• Enclosure Protection: Complies with API 670 requirements and Type 4 enclosure ratings.
• Hazardous Area Safety: Accommodates intrinsically safe and explosion-proof probes certified under CSA, ATEX, and IECEx schemes (Option 28 selectable approvals).