What is a stern tube Distance ring?

The stern tube distance ring – otherwise known as a spacer ring – is a key component in many stern tube systems. And RM Propulsion’s stern tube distance/spacer rings are ideal for meeting your vessel’s maintenance needs.

 

So, what is a stern tube distance/spacer ring?

The stern tube seals in oil-lubricated lip-type systems run on a chrome steel liner that protects the propeller shaft. In normal operation, these systems wear over time. In particular, the lip seals create grooves on the liner. However, lip seals require an unworn contact surface to ensure proper sealing and lubrication. Therefore, when the grooves in the aft system become too deep, the entire seal box must be moved to an unworn surface. This is often accomplished by adding or removing a distance ring between the seal housing and the stern tube. This will ensure that the seal lip seal runs on a grooveless surface, promoting proper sealing and lubrication.

Once there are two sets of grooves on the chrome steel liner, it should be removed and machined to produce a fresh, groove-free surface. This will leave it ready for another two seal overhaul periods. We recommend overhauling stern tube seals every five years.

 

Benefits of a distance/spacer ring: ‘Split’ design

A Distance ring can be installed without removing the propeller, making the process both time- and cost-effective.

 

Need a distance/spacer ring? Get in touch!

If your vessel requires a new stern tube distance/spacer ring, we can provide the high-quality parts you need. Our distance ring  is compatible most major brands, including *Simplex, *Kobelco, *Kemel, *Lagersmit and *Wärtsilä.

 

Contact us today for a quotation.

 

*RM Propulsion has no commercial relationship with the mentioned companies or brands on our website. We are an independent company in the marine industry.

Expertise at your service

Looking for an expert opinion? Our experts can quickly tell you whether a distance/spacer ring is suitable for your stern tube system or if other actions are required. With local service engineers in Turkey, Estonia, China and the Netherlands, RM Propulsion is well positioned to provide stern tube seal replacement services, in-depth inspections and troubleshooting, worldwide. We can also carry out afloat repairs if necessary.

We can help you with a range of issues:

  • Stern tube seal leakage
  • Oil leakage
  • Water ingress
  • Stern tube seal replacement

RM Propulsion’s spacer ring is ideal for meeting your vessel’s maintenance needs. And thanks to our dedicated expertise, we can help keep your fleet in excellent working order for years to come.