Chapter 7 (Cylinders) Flashcards
What’s a Check Valve?
A valve that only allows flow in one direction. Takes 5 psi to overcome spring releasing pressure. Valve fails if it breaks.
What is a cylinder?
The most common pneumatic actuator that provides straight line mechanical power/energy
What do wiper seals do?
Clean, wipe, and lubricate the cylinder rod
What’s a stroke adjuster do?
Shortens the cylinders travel in retract
Some cylinder mounting styles?
Cap fixed Clevis (articulate from blind side), head trunnion (for pivoting), cap square flange (rigid from blind side), and side lugs (rigid from side)
Common types of cylinders?
Single acting, spring returned, ram, double acting, single rod, and double rod. (Some can be arranged together)
What’s a stop tube do?
Helps save the rod gland bushing
What is rod buckling?
The sudden collapse of the rod at or above the critical thrust load
What causes rod buckling?
- The Axial loading
- The bending moment imposed on the rod
- The type of conditions on the cylinder (Ex: mounting style and what it’s mounted to)
Piston seal
Allows pressure to be applied to the cylinder to move it.
What do bushings do?
Guides cylinder rod
Rod seal?
If it fails it allows air to leak out causing cylinder to not have pressure or work.
Thrust load?
Cylinder extending. Worst thing that can happen is rod buckling
Tension load?
Cylinder in retraction. Threads are weak and rod can come off cylinder.
Ram cylinder?
Piston and rod are same diameter
Double acting cylinder
Causes power reversible motion
Blind side of cylinder
Has no rod
Rod end of cylinder
Has a rod
Cushion valves
Effects speed of cylinder at the end of a stroke to eliminate shock. Must be adjusted and won’t finish stroke if to tight
How do rotary motors work?
Pressure has to go in on the smallest volume area and when it expands it causes rotary motion. Exhaust must exit the largest volume area
