Seagull AS

Specialized Training for Oil Tankers

Task 4

Task 4.

Name:

ID no:

This task no. 4 must be mailed or sent by fax to Seagull A/S. Put your answers in an envelope marked “Task 4” and mail it.

Question 4.1.

How is the capacity to a centrifugal pump given?

Answer:

Question 4.2.

Why is a centrifugal pump equipped with a non-return valve on the delivery side?

Answer:

Question 4.3.

Give a short description how an ejector works.

Answer:

Question 4.4.

Below a performance curve for an ejector. The ejector has a suction lift of 5 meters and a delivery head of 10 meters. What is the specific ejector's maximum “suction capacity”, “driving water pressure” and “driving water consumption”?

Answer:

The ejector's Performance Curves

Question 4.5.

Explain the abbreviation NPSH with regard to centrifugal pumps.

Answer:

Question 4.6.

What is cavitation?

Answer:

Question 4.7.

On the next page a curve is shown with one centrifugal pump running. (The oil's density is 820kg/m³).

What is delivered with one pump?

What is the Mlc for one pump?

What is the manometer pressure for one pump?

Add one more pump in parallel with the first one (do it on the curve).

What is delivered with two pumps in parallel?

What is Mlc for two pumps?

What is the new manometer pressure?

Answer:

Question 4.8.

What is the most negative side of a centrifugal pump?

Answer:

Question 4.9.

What will happen if a centrifugal pump is fitted without a non-return valve on the delivery side?

Answer:

Question 4.10.

Describe the composition of vacuum strip.

Answer:

Question 4.11.

What is pressure surge?

Answer:

Question 4.12.

Under which conditions may pressure surge occur?

Answer:

Question 4.13.

What is the purpose of the emergency organisation?

Answer:

Question 4.14.

What will be the first action of a person who discovers an emergency?

Answer:

Question 4.15.

Which international convention dealing with fire-fighting arrangements etc.?

Answer:

Question 4.16.

What is jettison of cargo?

Answer:

Question 4.17.

What kind of information should be ready in case of an emergency?

Answer:

Practical task:

If you are on board a vessel this practical task must be done and mailed/sent to Seagull AS.

Make a schematic drawing of the equipment installed on your vessel, to prevent back-flow of inert gas from the deck lines and tanks to inert gas system / engine room.

Include on the drawing sensors and automatic devices.

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Author:	Kjell Vagtberg	Printed:	06.01.03
File name:	Task 4.doc	Version:
File created:	14.02.02	Approved by:
Last saved:	06.01.03	Approved date:

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