Bently Nevada 21128-04-02 Velocity Transducer Housing, NEMA 4X/IP65

Technical Specifications Breakdown

Key parameters for the 21128-04-02 are listed below for quick reference:

Industry Applications for the Protective Enclosure

Oil & Gas Refineries

In refinery units where washdowns and chemical spills are routine, the 21128-04-02 housing prevents water ingress and corrosion damage to velocity sensors monitoring pump vibrations. The 1/2-in NPT explosion-proof fitting allows safe cable routing in classified areas.

Water & Wastewater Treatment

Treatment plants expose sensors to high humidity and direct spray. The NEMA 4X-rated stainless steel housing resists corrosion from chlorinated water and cleaning agents, extending sensor life in grit chambers and clarifiers.

Power Generation

Turbine and generator bearing monitoring requires reliable vibration data. The housing’s wide temperature range (-29°C to +121°C) accommodates both cold startup conditions and heat near steam turbines.

Installation & Setup Guidance

Before installation, verify that the mounting surface is clean and flat to ensure proper sealing. Apply a suitable thread sealant to the 1/2-in 14 BSP mounting thread to prevent moisture wicking. For the cable exit, use a 1/2-in NPT conduit or fitting rated for the environment. When installing a Velomitor CT sensor, the tall cap option is required. Similarly, the tall cap is necessary for 9200 or 74712 Seismoprobe sensors with isolated bases. Use cable part number 89477-AA to connect the Velomitor sensor to a monitor.

Maintenance & Reliability

Periodically inspect the housing for signs of physical damage, corrosion, or seal degradation. Verify that the neoprene O-ring remains pliable and free of cracks. Clean the exterior with a mild detergent and water; avoid abrasive cleaners that could damage the stainless steel finish. Re-torque the cable fitting if loosened during maintenance. The housing is designed for long service life with minimal upkeep.

Robust Protection for Critical Velocity Measurements

Industrial environments expose velocity sensors to hose-directed water, corrosive agents, physical impact, and other damaging conditions. The Bently Nevada 21128-04-02 velocity transducer housing provides a rugged, sealed enclosure that safeguards sensitive transducers without compromising measurement accuracy. Constructed from 303 stainless steel, this housing meets NEMA 4X and IP65 requirements when properly installed, making it suitable for washdown areas and corrosive atmospheres.

Engineered for Harsh Conditions

The 21128-04-02 is designed for non-hazardous locations where moisture and corrosion are primary concerns. Its neoprene O-ring material ensures a reliable seal against moisture ingress, though the assembly is not submersible. The housing accommodates a 1/2-in 14 BSP (G 1/2-in) mounting thread and includes a 1/2-in NPT explosion-proof cable exit fitting for secure conduit connections.

Compatibility & Integration

The 21128-04-02 is compatible with Bently Nevada velocity sensors requiring a 1/2-in 20 UNF internal mounting thread (for 21128 and CA21128) or 5/8-in 18 UNF-2B (for BA42608). The tall cap option accommodates Velomitor CT sensors and specific Seismoprobe models. Always confirm sensor thread compatibility before ordering.

Selection Guide & Purchasing Advice

When selecting a velocity transducer housing, consider the environmental severity and sensor type. For non-hazardous, moisture-prone areas, the 21128-04-02 offers cost-effective protection. If you need a different mounting thread or cable exit, other 21128 variants are available. Contact AutoDCSTech for lifecycle status and availability before ordering. Our team can help match the housing to your sensor and application.

Please verify current lifecycle status and availability with AutoDCSTech before ordering.