Bulkhead Shaft Sealing: IT Really is Rocket Science

(Maritime Reporter & Engineering News
Friday, November 04, 2011

Midé Technology Corp., founded in 1989 by MIT PhD. Marthinus van Schoor, is a company created around the design and engineering of smart material based systems and solutions.  Historically, the company has not served any specific industry, in fact, it has served many of them, including: work on the international space station; energy harvesting systems on trains; underwater thermally controlled buoyancy systems; and, most recently, work with the U.S. Navy and the commercial marine industry.
In 2004, Midé won a contract from the U.S. Navy to develop a novel bulkhead shaft seal using one of its smart materials, hydrogel embedded foam, a need born out of a situation where a worn out bulkhead seals nearly led to catastrophe.
Typical bulkhead seals are based on a contacting design where a wearing material is always in contact with the spinning shaft, but Midé proposed to the Navy the use of a solution using hydrogel embedded foam for a non-contacting seal designed not to touch the shaft until a flooding event occurred.  When the water hits the foam the foam expands and engages a seal with the shaft.  The company dubbed these HydroActive seals, and the development ultimately led to Midé Marine.
Midé’s first product for the Navy was a retrofit solution, the Reliant Series RM; a product was designed to integrate with housings already installed on a specific Navy class of ships.  When the Navy contracted Midé to develop seals for a new vessel design, it wanted a standalone product sans the heavy housings.  To fulfill this need, Midé developed the Reliant YM (yoke model) bulkhead seal, which it has now supplied for two ships classes. 
In recent years, the company has developed and introduced a commercial grade seal called the Omni Series, which offers the same non-contacting HydroActive benefits as the Reliant Series for vessles with smaller shaft deflections than typical Navy ships require.  This reduced shaft deflection requirement leads to a simpler design and a lower procurement cost.

How it Works
Midé developed a robust and reliable hydrogel embedded foam that provides adequate force and displacement to engage a seal on the shaft. It is important to note that it is scalable to most any size shaft.  The process is completely reversible; the foam can be swelled and dried many times over.  Heat above a certain threshold actually causes the gel to expel water. While the full process by which the company creates the foam is understandably proprietary, it is worthy to note a number of operational benefits inherent in the design, installation and use of the seals, including:
•    Almost zero maintenance costs due to non-contacting nature of the design;
•    Safer seal as there is no opportunity for the seal to wear and fail
•    Lenient mounting requirements again due to non-contacting/floating nature of the design;
•    Unlimited shaft speed during normal operation; still operable during flooding, but speed is limited to 25 m/s surface speed.
•    Flexibility: Omni Series (commercial) seals range from 50 to 1000 mm, with a split design to ease installation for refit or newbuild.

Email: cludlow@mide.com
www.midemarine.com

(As published in the October 2011 edition of Maritime Reporter + Engineering News - www.marinelink.com)

Maritime Reporter September 2014 Digital Edition
FREE Maritime Reporter Subscription
Latest Maritime News    rss feeds

Technology

NAVTOR, AWT Agreement Marks Next Step in E-navigation

NAVTOR has signed an agreement with maritime weather routing specialist Applied Weather Technology (AWT) that will see the two companies integrating their services

BCG Upgrades Virtual GMDSS Simulator

Buffalo Computer Graphics (BCG) Inc. released an updated version of its Virtual Global Maritime Distress and Safety System (VGMDSS) Simulation software. BCG’s VGMDSS

Australia, US Order Anti-ship Missile Decoys

Design of the next generation of anti-ship missile decoys is set to commence following the signing of two contracts between the Australian Defense Force and BAE Systems Australia Pty Ltd.

Shipbuilding

Water-cooled WGM Motors From WEG

WEG, a supplier of drive technology, introduced its water-cooled WGM motors to the shipbuilding industry for the first time at SMM 2014. The WGM water-cooled induction motors are compact,

Henderson, Hanes & Associates Opens Doors in Miami

Ocean Engineering/ Naval Architecture Firm Brings Innovation to the Mega Yacht Community The Miami-based ocean engineering and naval architecture firm of Henderson & Associates, Inc.

Austal Launches Trenton (JHSV 5)

Second Joint High Speed Vessel to be launched at Austal in 2014 On September 30, 2014, Austal USA successfully completed the launch process of Trenton (JHSV

 
 
Maritime Careers / Shipboard Positions Maritime Security Navigation Offshore Oil Pod Propulsion Port Authority Ship Repair Ship Simulators Shipbuilding / Vessel Construction Sonar
rss | archive | history | articles | privacy | terms and conditions | contributors | top maritime news | about us | copyright | maritime magazines
maritime security news | shipbuilding news | maritime industry | shipping news | maritime reporting | workboats news | ship design | maritime business

Time taken: 0.0829 sec (12 req/sec)