Compressed gases in a hydraulic system can cause what?

• A. Foaming
• B. Cracking
• C. Sedimentation
• D. Overheating

Answer: (A)

When gas is present in hydraulic fluid under pressure, it forms bubbles that create foam. These gas bubbles disrupt the smooth, continuous flow and lubricating film the fluid normally provides. Foam makes the fluid less effective at transmitting pressure and can lead to irregular movement, cavitation, and increased wear on components. That’s why foaming is the result you’d expect from compressed gases in a hydraulic system. The other options don’t fit as well: cracking is about material failure, sedimentation is solids settling out, and overheating relates to excessive heat rather than the presence of gas bubbles in the fluid.