This article introduces how to renovate the open expansion system into a half_open system, not only ensure the security, but also protect the high temperature oil from contacting with the air.

• 介绍了如何将开式膨胀系统改进为半开式系统,既保证了系统的安全,又避免了高温热媒油与空气接触,从而保护了油的品质。