RBT-13 Rubber Bellows – Precision Engineered Flexible Seal
RBT-13 Rubber Bellows – Precision Engineered Flexible Seal
Overview
The RBT-13 is designed with a parallel single spring and is supplied with a rubber bellows and friction-drive collar which engages with the shaft to provide rotational movement to the seal faces.
The seal has a number of design features including a monolithic seal face and is supplied with a stationary seat as standard and is dimensionally equivalent to the Burgmann MG13.
Product Description
Technical Specifications
| Seal Shaft Sizes | 0.47” – 2.17” |
| Inboard Seal Face Combination | Car/SiC, Car/Cer, SiC/SiC |
| Bellows | EPDM |
| Shaft Speeds | Up to 10 m/s |
| Pressures | Up to 12 barg (174 psig) – Shaft Size Specific |
Typical Applications & Industry Use Cases
The RBT-13 is a rubber-bellows mechanical seal designed to deliver reliable sealing in light- to medium-duty rotating equipment. Its elastomer bellows offers flexibility and compensates for minor shaft misalignment or axial movement, making it suitable for equipment where rigid seals may fail due to vibration or shaft run-out. The RBT-13 is ideal for services with clean or moderately clean fluids and moderate operating conditions.
Industries Served
Water supply, domestic and municipal pumping
clean water, service water, utility services.
General industrial fluid transfer
non-aggressive liquids under moderate pressure and temperature.
HVAC, building services, and utility pumps
service water, chilled water, and circulation systems.
Light chemical or process pumping when fluid compatibility with the elastomer is ensured.
OEM or retrofit pump systems where a simple, cost-effective seal solution is desirable.
Equipment & Use-Case Scenarios
- Small- to medium-sized centrifugal pumps for which a compact seal package and flexible seal design are advantageous.
- Pumps with shafts that may experience slight misalignment, vibration, or thermal expansion — bellows seal helps absorb shaft movement while maintaining sealing integrity.
- Low- to medium-pressure and temperature applications that do not require heavy-duty or abrasive-service seals.
- Systems where periodic maintenance is acceptable and quick seal replacement reduces downtime.
Why It Fits These Applications
- The elastomer bellows design provides flexibility and compensates for shaft misalignment, reducing stress on seal faces.
- Bellows-type seals reduce or eliminate the need for secondary sliding seals, reducing leakage risk under vibration or dynamic shaft movement.
- Its compact and simple design suits pumps with limited stuffing-box space and simplifies installation and replacement.
- Rubber bellows offer adequate sealing performance for general-purpose, clean, or lightly contaminated fluid services without the cost and complexity of heavy-duty seals.
Installation Guidelines
Before installation, thoroughly inspect the pump shaft, seal chamber bore, and gland face; ensure the surfaces are clean, smooth, and free of scoring or corrosion.
Carefully slide the RBT-13 onto the shaft, ensuring the bellows is not twisted or stretched — proper orientation and a relaxed bellows position are critical.
- Lubricate sealing surfaces lightly with a fluid compatible with the elastomer to ease assembly and minimize the risk of damage during installation.
Tighten the gland/clamp evenly to avoid face misalignment. After installation, perform a controlled startup to check for leaks, vibration, or an unusual temperature rise before normal operation.
Maintenance & Inspection Best Practices
- Periodically inspect the bellows for signs of wear — cracking, hardening, swelling, or chemical degradation — especially if the pumped fluid contains contaminants or chemicals.
- Check the seal faces for wear, scoring, or pitting; if any visible damage is present, consider replacing the seal to prevent seepage or failure.
- Monitor pump alignment and vibration: excessive shaft run-out or vibration accelerates bellows fatigue and reduces seal life.
- For fluids that may contain particles or abrasives, consider adding filtration or pre-treatment; bellows seals are best suited to clean or lightly contaminated fluids.
- Schedule regular maintenance intervals based on operating hours, fluid properties, and duty cycles; replacing bellows or secondary sealing components before signs of failure extends seal life and reliability.
Service & Support Options
- Pre-installation review: confirm that fluid properties (chemistry and cleanliness), pressure, temperature, and shaft alignment are within the elastomer bellows seal service range.
- Spare parts kits include replacement bellows, sealing faces, gland hardware, and any ancillary components, enabling quick maintenance or swap-outs.
- On-site or remote commissioning assistance: verify proper installation, bellows seating, shaft alignment, and leak-free operation on initial startup.
- Preventive-maintenance scheduling: periodic inspection log, fluid condition tracking, and planned parts replacement to minimize unplanned downtime.
- Upgrade guidance: if fluid service becomes more demanding (e.g., aggressive chemicals, higher temperature, higher solids content), assess the need for a higher-duty seal design (e.g., a balanced mechanical seal or a bellows seal with more resistant materials).
Related Products
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
