RBW-125 – Precision Engineered Single Cartridge Seal
RBW-125 – Precision Engineered Single Cartridge Seal
Overview
HydroMax Seal RBW-125 | Metal Bellows Single Cartridge Seal with Quench, Drain & Flush Ports
The RBW-125 is a metal bellows, hydraulically balanced single cartridge seal equipped with quench, drain, and flush environmental ports, along with an outboard restriction bush for use with API Plan 62 and Plan 11 piping arrangements. Designed for parallel-rotating equipment shafts, this rotary bellows wet (RBW) seal features shrink-fitted seal faces and an O-ring secondary seal.
With material options including Hastelloy, AM350, and Inconel 718, the RBW-125 is well-suited for demanding applications that require superior thermal stability and chemical resistance. This seal comes factory assembled and tested to ensure reliable field performance.
Product Description
Design Features
- Hydraulically balanced rotary metal bellows seal
- Shrink-fitted seal faces for stability and long life
- Flush, quench, and drain ports compatible with API Plan 11 and Plan 62
- Outboard restriction bush for pressure control
- Set screw driven for secure shaft engagement
- O-ring secondary seals for effective dynamic sealing
- Available in various high-performance bellows materials
- Factory assembled and tested for ready-to-install performance
Technical Specifications
| Seal Shaft Sizes | 20mm – 100mm (1.000″ – 4.000″) |
| Inboard Seal Face Combinations | Car/TC Car/SiC TC/TC TC/SiC SiC/SiC |
| Gasket | Graphite |
| Bellows Material Options | Stainless / Hastelloy / Stainless Stainless / AM350 / Alloy C42 Inconel 625 / Inconel 718 / Inconel 625 |
| Inboard Wetted Parts | 316 Stainless Steel |
| Elastomers | Viton ERP Aflas Kalrez |
| Shaft Speeds | Up to 20 m/s |
| Pressures | Up to 16 Barg (232 psig) – Shaft Size Specific |
| Temperatures | Up to 180°C (356°F) – Bellows material specific |
WARNING:
Performance values are based on isolated variables. Do not apply maximum limits for pressure, speed, and temperature at the same time.
Typical Applications & Industry Use Cases
The RBW-125 Single Cartridge Mechanical Seal is a hydraulically balanced, metal bellows single-cartridge seal designed for parallel-shaft rotating equipment. It features integrated flush, quench, and drain ports, along with an outboard restriction bush, for enhanced fluid control and integration with environmental piping. The seal’s shrink-fitted faces and O-ring secondary seals provide dimensional stability and effective dynamic sealing. It is supplied factory assembled and tested for ready-to-install performance.
Industries Served
Chemical processing and corrosive fluid services
Petrochemical and refining systems
Water and wastewater treatment industries
Industrial and utility pumping systems
Power generation and heavy industrial fluid handling
OEM and custom rotating equipment applications
Equipment & Use-Case Scenarios
- Parallel-shaft centrifugal and process pumps requiring dependable internal wet sealing
- Services where controlled flush, quench, or drain fluid circulation improves lubrication and heat dissipation
- Installations needing a metal bellows design for high chemical resistance and thermal stability
- Applications where a ready-to-install cartridge seal reduces downtime and simplifies maintenance
Why It Fits These Applications
- Hydraulically balanced metal bellows reduces face loading and improves reliability
- Shrink-fitted seal faces maintain stability under pressure and temperature variation
- Flush, quench, and drain ports enable effective environmental control and cooling
- The outboard restriction bush helps regulate pressure and protect secondary sealing elements
- O-ring secondary seals provide dependable dynamic sealing
- Cartridge construction simplifies installation and minimises assembly errors
Installation Guidelines
Pre-Installation Preparation
Clean and thoroughly inspect the pump shaft, seal chamber bore, and gland surfaces. Remove corrosion, debris, or surface damage that could compromise seal alignment or face contact.
Seal Installation
Slide the RBW-125 cartridge seal onto the shaft and into the seal housing. Confirm the correct orientation of the flush, quench, and drain ports per the piping plan. Secure the cartridge evenly to prevent distortion.
Alignment & Fit
Ensure proper alignment of stationary and rotating components to maintain uniform face contact during operation.
Startup Procedure
Initiate any flush or environmental plan before starting the pump. Gradually bring the system to operating speed and pressure while monitoring for leakage, vibration, or abnormal temperature.
Maintenance & Inspection Best Practices
- Routine Visual Inspections: Check for leakage, vibration, or abnormal heat near the seal area
- Seal Face Monitoring: Inspect faces for wear, scoring, or deposits during planned shutdowns
- Metal Bellows Assessment: Examine the bellows for fatigue, corrosion, or deformation
- Operational Tracking: Maintain records of pressure, temperature, and shaft speed to aid predictive maintenance
- Spare Components: Keep replacement O-rings, faces, and bellows assemblies readily available
Service & Support Options
- Application Verification: Confirm materials and configuration suit fluid chemistry and operating conditions
- Installation Support: Technical assistance can help ensure correct setup and first-run performance
- Preventive Maintenance Planning: Schedule inspections and replacements based on duty severity
- Upgrade Evaluation: For more demanding conditions, consider enhanced materials or alternate seal designs
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Contact HydroMax Seal
Contact HydroMax Seal today for innovative solutions, expert guidance, and over a century of engineering excellence. Your journey to mechanical sealing excellence starts with HydroMax Seal!
E-Mail: sales@hydromaxseal.com
Address: 18511 Beaumont Hwy Building D
Houston, TX
77049







