Throttle flange is used for throttle installation; it's welded on the main air intake pipe of engine to connect with throttle.

节气门安装法兰主要用于节气门的安装，节气门安装法兰焊接在发动机的进气总管上方以方便节气门和发动机的进气总管的连接。

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The engine may include a main housing (20) defining a compressor compartment (22) and an air intake housing (24) mounted to the main housing.

该涡轮发动机包括限定一 压缩机室（22）的主壳体（20）和安装在主壳体上的进气壳体（24）。

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In the days following the attacks, guards were placed in front of two large air intake ducts that provide the main external air supply to the Capitol building, sources have told CNN.

CNN: U.S. Capitol getting security overhaul