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 July 2015 Digital Edition
FREE Maritime Reporter Subscription
Latest Maritime News    rss feeds

Technology

INTERSCHALT VDR Earns CCS Certification

INTERSCHALT maritime systems AG, the provider of maritime software, services and systems for navigation and communications systems (NavCom) and manufacturer of Voyage Data Recorder (VDR) systems,

Nautilus Awards Contract for Dewatering Plant Design

Nautilus Minerals Inc. has awarded a contract for the design of the Solwara 1 dewatering plant to be used on the company’s production support vessel to the Brisbane

McMurdo Introduces Real-time Fleet Management

McMurdo  has announced PRISMA Connect, a web-based integrated fleet management system that connects ship to shore in real-time for improved communication and operational efficiencies,

Shipbuilding

Brazilian Police to Probe Nuclear Submarine Program

Brazilian federal police are investigating potential irregularities in a military program that aims to build a nuclear-powered submarine in partnership with France by 2023, newspaper Folha de S.

General Dynamics Tops Q2 Estimates

General Dynamics Corp, a maker of ships, tanks and business jets, reported higher-than-expected quarterly earnings and revenues on Wednesday, and sharply raised its outlook for full-year profit.

Eastern Launches Second MPSV for Hornbeck

Eastern Shipbuilding Group, Inc. has launched the second of two 302’x76’x26’ multipurpose service vessels in the HOSMPSV 310ES series for Hornbeck Offshore Services, LLC.

 
 
Maritime Careers / Shipboard Positions Maritime Standards Naval Architecture Navigation Pipelines Port Authority Ship Electronics Ship Simulators Sonar Winch
rss | archive | history | articles | privacy | 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: 0.1191 sec (8 req/sec)