The Dynamics Of Braking System

Marine engineering students Ika Suwandi, left, Deny Suriyono and
Yuda Apri explain the dynamics of their braking system, which uses
waterjets to slow ships. (JG Photo/Amir Tejo)

Marine engineering students Ika Suwandi, left, Deny Suriyono and Yuda Apri
explain the dynamics of their braking system, which uses water jets to
slow ships. (JG Photo/Amir‚Tejo)

Young Inventors Put Brakes on Ship Collisions

Ever wondered how ships slow down?

Judging from the high number of shipping collisions, whatever braking
system vessels are currently using seems to be somewhat ineffective.

That is what's been exercising the minds of three students from the
Surabaya Institute of Technology (ITS).

Ika Suwandi, from the school of marine engineering department, Deny
Suriyono, from the naval architecture department, and Yuda Apri, from the
ship engineering department, became interested in the problem when they
saw that 55 of the 208 marine accidents between 2004 and 2008 were
collisions.

And was this at a time when navigation equipment is becoming more
sophisticated.

Perhaps the ships brake system was not working effectively,Ika said.

The three studied the conventional brake system with an eye to uncovering
its weaknesses. It is based on a reversal of a ship's propellers.

This system showed several weaknesses. It could not bring ships to a
sudden halt because of the time and distance required to reverse the
propellers, which depended on their size. And the propellers were prone to
break if suddenly thrust into reverse.

After months of studies and experiments under the tutelage of lecturer
Hasan Ikhwani, the students came up with a ship brake based on propulsion
from water jets.

They used the very system employed to move superfast ships to brake ships
effectively.

Water is drawn from under the boat into a pump-jet on the boat and then
expelled through a nozzle.

The system was first developed to propel boats in the 1950s in New Zealand.

“With the use of water jet propulsion, ships can be halted more
effectively,Ika said.

To maximize its effectiveness, the system was installed in the bow, or the
front, of the ship.

Following laboratory testing and field tests, a ratio of 1:2 was reached
for the strength of the water jet necessary to halt a ship effectively.

Under such ratio, a ship travelling at 20 nautical knots would need jets
that would be able to move the ship at half that speed.

Ika said tests had shown that if the ratio was changed, with a higher jet
speed, the brake system would become ineffective because the stern would
lift up as the boat got projected in the opposite direction, and the boat
could also reverse too much.

The head of the National Ship Design and Engineering Center, Aires
Sulisetyono, took his hat off at the students creativity. This could
become a solution to an important problem in the shipping world,Aries
said.

John Sihombing, the general manager of the Surabaya branch of the state
shipping line PT Pelni, said it might be able to lower the number of naval
incidents.

It should be shared with shipping associations,he said.

--

http://www.its.ac.id

BES REPAIR - HULL REPAINTING PROCESS (CONTINUED)

Please watch the movie as follow :
http://www.youtube.com/watch?v=N42kYASrNcM

BES REPAIR - HULL REPAINTING PROCESS

http://www.youtube.com/watch?v=0TwMqeP7EOk

Hazard Description

• Solvents (e.g., aliphatic and aromatic hydrocarbons, various ketones) can create both health and fire hazards.
• Pigments, anti-fouling and anti-rust paint components (e.g., organo-mercury compounds, copper oxide, arsenic, organo-tin compounds, cadmium, chromium).
• Types of paints used include: anti-rust paints that contain lead(e.g., red lead paint), zinc chloride primer paints, hot plastic rust preventive and anti-fouling paints, copper-bottom paints, and fire-resistant paints.

Scenarios/Injuries

• Ship-board painting is often performed in confined spaces and tanks, thereby concentrating fumes and particulates. In addition to health hazards, the opportunity for fires and explosions increases.
• Lead poisoning can occur from ingestion and inhalation of lead-based paint particles. The exposure depends on the method of application; for example, rolling versus spraying. Exposure to other hazardous constituents of paints can occur in the same way.

Controls

• For standards covering painting operations in shipbuilding and repair.
• Respiratory protection is provided using air-line and air-purifying respirators.
• Mechanical air supply and exhaust are used to ventilate confined spaces and control exposures during painting operations.
• Spray nozzles can be mounted on extensions, thereby lessening exposure to paint components and improving visibility by reducing the amount of paint covering goggles and face shields. In some situations, application using brushes may provide the most satisfactory control.
• Painting with lead-based paints can be done at night when other workers will not be exposed. Supplied-air respirators are often required to avoid exposure. For the standard covering occupational exposures to lead.
  

Prompted The Government Added A Pioneering Vessel In Enggano

Residents Enggano Island, North Bengkulu District Enggano asked the government to increase cruise ship schedule pioneer than once within 10 days to two per 10 days.
Chief Coordinator Enggano Island Kauno Iskandar Zulkarnain said the request was to increase economic activity on the island of Enggano, North Bengkulu Regency.
"Moreover, there are plans Enggano King ferry will be helped to the Peacock-Bakauheni. We hope to schedule a pioneer can be expanded, "he said, today.
He explained he had not yet received information about the successor of King Enggano ship which has been the mainstay of transportation in the island's residents to the city of Bengkulu.
When the vessel is conjunct without a replacement ship, the voyage to the island is 106 miles from Bengkulu city is served only ship once a pioneer with the schedule in 10 days.
"If only the pioneer, the fishing vessel would have difficulty transporting the catch. During this time the ferry twice a week into Enggano, "he added.
To that end, Alexander expects the government to increase the schedule for the ship pilot who was not only serving the city of Bengkulu-island routes Enggano, but also the Port District Linau Bayur Kaur and the Gulf, West Sumatra.
Meanwhile, the Head of Transport Department of Communication and Information Bengkulu Province Ali Berti says still waiting for a replacement vessel that will ferry the King Enggano helped overcome bottlenecks in Merak-Bakauheni.
"Prior to his successor arrived in Bengkulu, we can not let go because the community of King Island Enggano Enggano highly dependent on this ship," he said.
He said the ferry King of Enggano requested by the Director General of Sea Transportation Ministry of Transportation Sunaryo to help overcome bottlenecks in Merak-Bakauheni for 3 weeks.
During the ship is located in the Sunda strait, PT Transportation River Lake Crossing (ASDP) will provide one replacement vessel of Aceh.
"The information, a replacement ship was still on the journey, so before it arrived in Bengkulu, we will not release the King Enggano, we see in two or three days," he added.
Crossing from Bengkulu City Enggano Island ferry which served the two ships and one ship of King Enggano pioneer.King Enggano navigate this route twice a week, while one-time pioneer ship in 10 days. BI