PPH chapter 7.2

Minor internal leakage (round the piston in a double-acting cylinder, for example) can be of little consequence and may even be deliberately introduced to provide ___ of the moving parts.

• lubrication

• filtration

• friction

• replacement

Answer explanation

lubrication for moving parts

Which of the following is the TWO different type of seals introduced during this chapter?

(you can choose more than 1 answer)

• static seal

• dynamic seal

• rotating seal

• split seal

• teflon seal

Answer explanation

static and dynamic seal

What is the most common type of static seal?

(You can choose more than 1 answer)

• Composite Seal

• U ring

• Cup Seal

• O ring

Answer explanation

O ring only

What is the most common type of dynamic seal?

(You can choose more than 1 answer)

• Composite Seal

• U ring

• Cup Seal

• O ring

Answer explanation

ALL except O ring

What type of seal is shown here?

• Composite Seal

• U ring

• Cup Seal

• O ring

Answer explanation

O ring

What type of seal is shown here?

• Composite Seal

• U ring

• Cup Seal

• O ring

Answer explanation

Cup seal

What type of seal is shown here?

• Composite Seal

• U ring

• Cup Seal

• O ring

Answer explanation

U ring

What type of seal is shown here?

• Composite Seal

• U ring

• Cup Seal

• O ring

Answer explanation

Composite seal

What do you introduce to prevent creep problem in dynamic seal?

• Anti extrusion ring

• Anti intrusion ring

• O ring

• U ring

Answer explanation

Anti extrusion ring

Which of the following materials are commonly used in making seals for pneumatic system?

(You can choose more than 1 answer)

• Cork

• Neoprene

• Buna-N

• Teflon

• Viton

Answer explanation

In pneumatic systems Viton (–20°C to 190°C) and Teflon (–80°C to +200°C) are the most common materials.