KUMPULAN 5CASE STUDY 1: PRODUCT PROPELLER

MUHAMMAD AZRI BIN AZMAN D20111050147 NUR AINA NASIHAH BT MOHAMAD ASHRI D20111050157 NOOR HASYILA BT MOHD ISA D20112052137 SITI HAJAR BINTI YAZID D20112052142 FARIHIN BINTI MD FAUZI D20112052143

PROPELLER• A propeller is a rotating fan like structure

which is used to propel the ship by using the power generated and transmitted by the main engine of the ship.

• The transmitted power is converted from rotational motion to generate a thrust which imparts momentum to the water, resulting in a force that acts on the ship and pushes it forward.

Types of Propeller• Propellers are be classified on the basis of

several factors. The classification of different types of propellers is shown below:

Classification by Number of Blades Attached:Propeller blades may vary from 3 blade propeller to 4 blade propeller and sometimes even 5 blade propeller. However, the most commonly used are 3 blades and 4 blade propellers.

a)3 blade propeller:- The manufacturing cost is lower than other types.- Are normally made up of aluminium alloy.- Gives a good high speed performance.- The acceleration is better than other types.- Low speed handling is not much efficient.

b) 4 blade propeller:- The manufacturing cost is higher than 3 blade propellers.- Have better strength and durability.- Gives a good low speed handling and performance.- Has a better holding power in rough seas.- 4 blade propeller provides a better fuel economy than all the other types.

c)5 blade propeller:- Manufacturing cost is higher of all.- Vibration is minimal from all the other types.- 5 blade propellers have better holding power in rough seas.

TYPE OF MATERIAL USED

Propellers are made of aluminum or steel and both have their advantages and disadvantages. Unlike other prop features, the choice of material is really more a matter of preference.

Aluminum Steel

Choose Aluminum Blades For : Choose Stainless Steel Blades For:

Lower costProtective coatingLight weight (weighs about

1/2 as much as steel)Satisfactory performance in

most situationsLess expensive to repair

Higher performanceRepairs closest to brand

new conditionBlade strength prevents

flexing under pressure; blades remain in optimal condition longer

Durability and lower susceptibility to damage .

THE PRODUCTION PROCESS OF THE

PRODUCT

The production process of the propeller

ToolingFirst, the propeller has to be digitalized.

Through the CNC milling a reverse of the propeller is cut into a solid piece of aluminum, this creates the tooling.

The tooling is a hollow version of the propeller used to inject wax into.

• The “Lost Wax” process

Once the tooling is completed, it is injected with melted wax. • This is the first stage • That is the “lost wax” process. • After the propeller is created in wax, • it is dipped several times into a ceramic material until a thick shell

covers the entire wax propeller. After the ceramic shell has completely dried,

• the wax is melted out and replaced with molten stainless steel. • Once the stainless steel has cooled, the shell is removed you are

left with a rough casting of the propeller.

Finishing the propeller

~ Once the casting is inspected for the proper dimensions, it is hand ground with three different grits of sandpaper. ~ For the final process, the propeller is placed into a two stage surface finishing machine. ~ This machine gives the propeller its reflective finish.~ Every propeller produced through Signature propellers is made with a quality craftsmanship ~ that is insured to give every boat the best performance possible.

THE SUITABLE HEAT TREATMENT PROCESS

FOR THE PRODUCT BASED ON ITS APPLICATION

• The wax is warmed to 180 degrees and poured into a "wax press,"

where a machine operator creates a pattern in the shape of the propeller.

• Then it's dipped four more times in a secondary finish that improves thickness and strength. In between each dipping, there is another five-hour drying period.

• The pattern is left to dry under high-powered fans for 24 hours. The entire dipping process takes more than two days.

• The wax pattern can be removed. Each piece is placed in an autoclave where the molds are steam-heated for 18 minutes at 325 degrees Fahrenheit at 100 PSI of pressure.

• During the cycle, the wax melts and separates from the shell and is later collected and recycled for future patterns.

• Next, the empty cavity, now free of most wax, is placed in a burnout furnace. Inside, the furnace reaches more than 2000 degrees Fahrenheit.

• While the molds are in the burnout furnace, an hour-long process,

500 pounds of stainless steel is melted at 3000 degrees Fahrenheit.

• After the shells are removed from the furnace, the liquid metal is poured inside the cavities from a ladle 50 pounds at a time.

• The process continues until all 500 pounds of melted metal are poured. Usually, that equates to 24 average propellers or 10 pod or Zeus-drive props.

• Shells are then cooled on carts for about an hour before they are transferred to the cleaning cell.

END