How to handle our Sterntube Seal ?

Sterntube Seal & Components

History

SIMPLEX STERNTUBE - SEAL
1948

The Simplex Sterntube Seal, a prerequisite for the use of oil-lubricated propeller shaft bearings.

SIMPLEX COMPACT - SC1

1970

 The Simplex-Compact Seal continues the extraordinary advance of our seal concept throughout the world.

SIMPLEX COMPACT - SC2

1992

Introduction of the 3rd Generation Simplex-Compact SC 2000 Sterntube Seal

SIMPLEX sterntube seals (stern tube seals)

Seals for oil and water lubricated sterntubes

Compact (SC1) and Compact 2000 (SC2)   
Size 155 - 1250 non split version
Size 140 - 1000 split version

Conventional
No longer manufactured - but spares are available
Size 155 - 800

SIMPLEX-COMPACT airspace sealing system

Airspace seal

This anti-pollution seal uses four self-supporting lip rings and incorporates an air chamber with controlled venting an no loss of air into the seawater. The system also has the ability to be switched over to a standard seal with a pressure control system in times of emergency.

As with other Simplex seals the lip rings can be replaced without uncoupling the tail shaft or removing the propeller.

This airspace seal installation diagram shows the latest standard with a pipe connection between seal and oil tank at the bottom of the seal and an additional oil chamber vent pipe connected on top of the seal. This revised design offers the opportunity to fill the oil chamber via the oil tank and vent the chamber at the same time. 

SIMPLAN sterntube seals (stern tube seals)

For small shaft diameters and water lubricated sterntubes, vessels using inland water ways, coastal vessels, yachts and high speed naval or coastal protection applications.

Frequently asked questions
What's in the service package?	Everything that is required to change the seals including the precise alignment of the liner.
Can the job be done afloat?	If the ship can be ballasted by the bow so that the shaft is out of the water then the seals can be bonded provided there is no other damage.
How long will the job take?	Three days for a standard forward and aft seal on the one shaft, provided that other dry dock work does not interrupt our work. CPP installations and split liners will take longer.
Can we replace the sealing rings without pulling the shaft?	Yes, by cutting the sealing rings, then vulcanising the rings with the aid of a bonding kit, and special two component adhesive.
What am I likely to need to do at the next docking?	Contact Your maker. They will check their service reports and advise what spares are required. For instance, a distance ring may be required, or the liner may need to be machined or a new liner needed.
Why are my seals leaking?	All seals require a small migration of liquid particles under the sealing ring in order to ensure that the ring is lubricated and cooled. Any water is accumulated in the Number Two chamber and transfered back to the 20 litre tank where it can be drained off. A leakage of up to 1% of the shaft diameter is acceptable.
I have 5% oil in the sterntube oil. What should I do?	Excessive leakage may be caused by a large number of factors for example: ·         Excessive wear seal lips ·         Hard and/or cracked seals ·         Broken or damaged seal springs ·         Foreign bodies under seal lips (fishing line, sand etc) ·         Damage to seal housing ·         Seal liners excessively grooved ·         Pitting corrosion in liners ·         Damaged gasket or 'O' seal on liner (aft seal) ·         Damaged 'O' seal between liner and clamp ring (forward seal) ·         Excessive eccentricity on liners ·         Wrong oil in system (possible corrosive effect on seals) ·         Liners machined under minimum permissable size ·         Excessive clearance between sterntube bearings and propeller shaft. (Vibration can cause pumping effect of oil or water past seals) ·         Damaged housing gasket

 

The process in pictures

1. cutting away the old seal	2. cutting the ring
3. bonding the ring	4. the finished ring

 (information taken from www.sterntubeseals.com)

PT PAL Indonesia delivered Escorts tug boat 4.400 HP

www.pal.co.id that PAL INDONESIA, on October 1, 2010, once again proving commitment by sending a vessel capacity of Escort Tug Boat 4400 HP (Horse Power), Hull No. W000262 ship the first of four ships Escort Tug Boat 4400 HP in a message with JGC / PT. KBR Indonesia Join Operation. Booking this ship is a form of Joint Operations trust company to the national shipping industry.

Based on experience since 1980 PAL INDONESIA has completed construction of the ship more than 160 types and sizes of ships for its warships and merchant ships. For products ship Commerce until 50.000 DWT size, and has been producing various types and sizes of ships, including ships Tanker, Container Vessel, Passengers Ship and  AHTS Ship, Tug Boat and Ship Escort Escort Tug etc. Tug Boat with HP 4400 is first ship from four ships in the message by JGC / PT.KBR Indonesia Merge Operations, while the second ship in their schedule will be proposed at the end of this year and then followed by third and fourth.

Escort Tug Ships HP 4400 is specifically designed to operate in order to support the activities of the Tangguh LNG project in Papua and the ship is equipped with a fire extinguisher in the sea (Fire Fighting One) and the ship was built based on standard plate; Loyd Registration and Classification Bureau of Indonesia (Duble Class), mounted ASD (Asymptote Stern Drive) that can create a very agile ship with more than 3000 KW and power Towing Winch mounted so that this ship has the ability to Auto Rendering.

Specifications Escort Tug boat 4400 HP follows:

Length overall: 32.00 Meters

Long Perpendicular: 26.67 Meters

Width: 11.60 Meters Draft: 5:36

Water Draft Meter Design: 4.10 Meters

Main engine: 2 x 2200 HP

Maximum speed not less than: 12 knots.

 

With the implementation of the handover Escort Tug Boat 4400 HP is expected in future cooperation that already exists can be improved again, so that the ship is required by PT JGC / KBR Joint Operation Indonesia can be met in the country, The synergy between PAL INDONESIA, with KBR JGC / PT Indonesia Joint Operation in the procurement of ships should be developed not only for the construction of new vessels, but also in repair and maintenance of other ships in order to participate to support the readiness of operational tasks and support the operation of the Tangguh LNG project so that in the present and the future of Indonesia to develop the Maritime Industry more advanced