🔍 Key Concepts

• Fire-resistant hydraulic fluids characteristics (viscosity, lubricity, seal compatibility) • Relationship between hydraulic fluid and sealing materials (O-rings, gaskets, hoses) • What must always be checked when changing to a different fluid type in an existing system

💭 Think About

• Ask yourself: when you substitute a new type of hydraulic fluid in an existing system, what is the one thing that could cause leaks or failures if it’s not checked first? • Consider which choice describes a condition that applies to every hydraulic system using special fluids, not just certain designs or operating conditions. • Think about what part of the system physically contains the fluid and is most sensitive to its chemical properties.

✅ Before You Answer

• Verify which option deals with material compatibility rather than operating characteristics like heat dissipation or pressure changes. • Check which choice would, if ignored, most likely lead to seal swelling, shrinking, cracking, or leakage. • Make sure the option you choose is something that must be confirmed before filling the system with the new fire-resistant fluid.