Table of Contents
- 1 What are the design considerations for a piston?
- 2 What are two criteria for design of the piston pin?
- 3 How the thickness of piston head is determined?
- 4 When the thickness of the piston head is 6 mm or less?
- 5 When the thickness of piston head is 6mm or less?
- 6 What is the design criteria of gudgeon pin?
- 7 How thick are piston heads?
- 8 What is the process of design of crank shaft?
- 9 What are the common materials used for Pistons of an engine?
- 10 What is piston clearance?
- 11 How do you calculate the stress on a piston crown?
What are the design considerations for a piston?
In designing a piston for an engine, the following points should be taken into consideration: It should have enormous strength to withstand the high pressure. It should have minimum weight to withstand the inertia forces. It should form effective oil sealing in the cylinder.
What are two criteria for design of the piston pin?
inertia forces due to reciprocating parts. (ii) It should have sufficient rigidity to withstand thermal and mechanical distortions. through the piston rings and the skirt. (iv) It should have minimum weight to reduce the inertia force due to reciprocating motion.
How are piston heads manufactured?
A punch press and dye are pre-heated while the slug moves through an oven, heating it to the same temperature as the punch press. The slug is then removed from the oven, and placed into the punch. The press applies 2,000 tons of pressure onto the slug, forging it into the basic shape of a piston.
How the thickness of piston head is determined?
Heat Flow through the Piston Head (H) On the basis of the heat dissipation, the thickness of the piston head is given by: H = [C x HCV x m x BP] = 0.05 x 47000 x 0.25/3600 x 4 =0.6527 KJ/s tH = H/(12.56 x k (Tc – Te)) = Hx1000/12.56 x 174.15 x 75 =3.98mm.
When the thickness of the piston head is 6 mm or less?
Clarification: When the thickness of the piston head is less than 6mm, ribs are not required hence the answer, thickness of ribs 1.6 to 2.5mm is wrong.
What is the highest point reached by the piston head?
In a reciprocating engine, the dead centre is the position of a piston in which it is either farthest from, or nearest to, the crankshaft. The former is known as Top Dead Centre (TDC) while the latter is known as Bottom Dead Centre (BDC).
When the thickness of piston head is 6mm or less?
Explanation: When the thickness of the piston head is less than 6mm, ribs are not required hence the answer, thickness of ribs 1.6 to 2.5mm is wrong.
What is the design criteria of gudgeon pin?
The gudgeon pin is typically a forged short hollow rod made of a steel alloy of high strength and hardness that may be physically separated from both the connecting rod and piston or crosshead. The design of the gudgeon pin, especially in the case of small, high-revving automotive engines is challenging.
How pistons are arranged in piston motors?
The pump consists of several hollow pistons inside a stationary cylinder block. An alternative form of piston pump is the axial design of Figure 2.14, where multiple pistons are arranged in a rotating cylinder. The pistons are stroked by a fixed angled plate called the swash plate.
How thick are piston heads?
Measured thickness of the piston head is 3.5 mm and it is agreed with the value of calculated thickness.
What is the process of design of crank shaft?
The design of the crankshaft is four stroke engine. The working cycle includes four processes such as intake stroke, compression stroke, expansion stroke and exhaust stroke. In this design process, the first step is to determine the engine cycle parameters.
What is design criteria of IC engine cylinder?
1. It should have enormous strength to withstand the high gas pressure and inertia forces. 2. It should have minimum mass to minimize the inertia forces.
What are the common materials used for Pistons of an engine?
Cast Iron, Aluminum Alloy and Cast Steel etc. are the common materials used for pistons of an Internal Combustion Engine. Cast Iron pistons are not suitable for high-speed engines due to its more weight. These pistons have greater strength and resistance to wear.
What is piston clearance?
The space between the cylinder walls and pistons is known as piston clearance. The diameter of the crown is slightly less than at the skirt due to variation in the operating temperatures. Again the skirt itself is also slightly tapered to allow for unequal expansion due to the temperature difference.
What are the different types of design parameters necessary for gear design?
Types of design parameters necessary for gear design Parameters needed for gear design are shown below. (Figure 4-2) 1. Tip circle 2. Reference circle 3. Base circle 4. Root circle 5. Tip diameter 6. Reference diameter 7. Base diameter 8. Root diameter 9. Addendum 10. Dedendum 11. Tooth depth 12. Facewidth 13. Center line 14. Center distance 15.
How do you calculate the stress on a piston crown?
Theoretical Stress Calculation: The piston crown is designed for bending by maximum gas forces Pzmax as uniformly loaded round plate freely supported by a cylinder. The stress acting in MPa on piston crown: σb=Mb/Wb=Pzmax(ri/δ)2