Day 4 Progress Check Flashcards
(15 cards)
Why is valve clearance in the valve train important?
To ensure valve closes completely
In an opposed engine, what drives the valve mechanism?
A camshaft
What is the primary function of the cam ring in a single-row radial engine?
To help control the timing of valve movements
What material is often used for constructing exhaust valves in aircraft engines?
Nichrome, silchrome, or cobalt-chromium steel
In a single-row radial engine, how is the cam ring typically located?
At the front end of the power section
What does being twice the size of a crankshaft gear do to a cam gear?
It allows the camshaft to move at twice the speed of the crankshaft
What material is often used for constructing intake valves in aircraft engines?
Chromic-nickel steel
What transmits the lifting force from the cams to the valves?
Rocker Arms
What is the function of valve springs in an aircraft engine?
To close and hold the valve securely on the valve seat
What determines valve lift and valve duration (length of time the valve is held open) in an aircraft engine?
The shape of the cam lobes
Which part of the valve operating mechanism is responsible for transmitting the lifting force from the cam to the valves?
Rocker Arms
Are intake valves for low power engines usually flat headed?
Yes
What does a sodium chamber filled with metallic sodium do in hollow-head mushroom type valve?
act as an excellent heat conductor
Which part of the valve operating mechanism converts rotational movement of cam lobe to reciprocating motion to push rod, rocker arm and valve tip to open valve at proper time?
Tappet Assembly
What’s the importance of valve clearance when it comes to cam followers?
To ensure the valve closes completely
