One Flashcards
(25 cards)
What is the aim of the procedure described?
To prepare a sand mould cavity using Dumb-Bell (Split Pattern)
This involves creating a mold for casting purposes.
List the materials required for the procedure.
- Molding sand
- Molding board
- Molding flask
- Shovel
- Parting sand
- Sprue pin
- Riser pin
- Trowel
- Draw pin
- Lifters
- Gate cutter
- Bellows
- Vent rod
- Dumb-Bell pattern
These materials are essential for creating the sand mold cavity.
What tools are required for the operations?
- Riddle
- Rammer
- Strike-off bar or Strike Edge
- Slick
These tools are used to manipulate and prepare the molding sand.
Fill in the blank: The first step in the procedure involves placing the pattern on the molding board with its flat side facing _______.
[the board]
What should be done after placing the drag over the board?
Give a clay wash inside
This helps in preventing the sand from sticking to the drag.
What is the purpose of sprinkling parting sand on the pattern and molding board?
To prevent the sand from sticking to the pattern
Parting sand facilitates the easy removal of the pattern from the mold.
How deep should the loose sand cover the pattern during the preparation?
2 to 3 cm
This depth ensures adequate coverage for molding.
What is the significance of packing the molding sand around the pattern?
To create a solid mold that retains the shape of the pattern
Proper packing is crucial for mold stability.
What tool is used to strike-off the excess sand from the top surface of the drag?
Strike-off bar
This ensures a smooth and even top surface for the mold.
What should be done after striking off the excess sand?
Blow-off the loose sand particles with the bellows and smoothen the upper surface
This step is important for finishing the mold surface.
What is the distance for placing the sprue pin from the pattern?
Place the sprue pin at about 5 to 6 cm from the pattern on the other side of the riser pin.
What should be done to the upper surface of the mold?
Sprinkle the upper surface with parting sand.
What is the next step after sprinkling parting sand?
Repeat steps 3 to 7, approximately.
How deep should the holes made with the vent rod be?
Make holes with the vent rod to about 1 cm from the pattern.
What should be done with the sprue and riser pins?
Remove the sprue and riser pins by carefully drawing them out. A funnel-shaped hole is made at the top of the sprue hole, called the pouring cup.
What should be done with the cope after lifting it?
Lift the cope and place it aside on its edge.
What is the purpose of the draw pin?
Insert the draw pin into the pattern. Wet the edges around the pattern. Loosen the pattern by rapping. Then draw the pattern straight up.
What should be done if the mold needs adjustment?
Adjust and repair the mold by adding bits of sand, if necessary.
What is the purpose of cutting a gate in the drag?
Cut gate in the drag from the sprue to the mold.
What should be done to the mold before closing it?
Blow off any loose sand particles in the mold.
How should the mold be closed?
Close the mold by replacing the cope and placing weights on it.
What is a precaution regarding the sand’s moisture?
Do not get the sand too wet. Water is an enemy of molten metals.
What ventilation precaution should be taken?
Provide adequate ventilation to remove smoke and fumes.
What safety measure should be taken during pouring?
Never stand near or look over the mold during the pouring because the molten metal might be too hot.
