808556-1 Intermediate Pressure Check Valve

中压单向活门

一、名称

Intermediate Pressure Check Valve

中压单向活门

二、件号

808556-1,S210T120-126

三、章节号

36-12-16

四、适用机型

B747/B757/B767

五、系统

36 PNEUMATIC

气源

六、安装位置

发动机短舱

七、部件原理

1. Description (Figure 1)

A. The intermediate pressure check valve has a vacuum cast Inconel 718 housing and valve poppet. The poppet shaft is attached to the poppet with a swaged pin and collar and the shaft is guided by a sleeve in the housing.

B. The poppet shaft and sleeve can be replaced without removing the valve seat. This feature improves valve maintainability. When the poppet is in the open position it stops on its outer rim. This reduces poppet rotation and minimizes shaft and sleeve rotational wear.

C. The valve is sized to function in a nominal 5.5 inch intermediate pressure bleed air duct. The valve contains a pressure sensing boss for the Boeing 757 application only. For all other applications the boss is plugged.

D. The check valve does not have an identification plate. The identification markings are put directly on the check valve housing.

1.说明（图1）

A.中压单向活门有一个真空铸造的Inconel 718外壳和提升阀。阀轴通过锻造销和轴环连接到提升阀上，轴由壳体内的套管导向。

B.无需拆卸阀座即可更换阀轴和套管。此功能提高了活门的可维护性。当提升阀处于打开位置时，它停在其外边缘上。这减少了提升阀的旋转，并最大限度地减少了轴和套管的旋转磨损。

C.活门的尺寸设计为在标称5.5英寸的中压引气管道中工作。该活门包含一个仅适用于波音757应用的压力传感凸台。对于所有其他适用性，凸台都是堵塞的。

D.单向活门没有铭牌。识别标记在单向活门壳体上。

2. Operation (Figure 2)

A. The intermediate pressure check valve is located in the intermediate pressure bleed air duct between the engine bleed outlet and the air supply precooler or between the engine bleed outlet and pressure regulating valve when the regulating valve is used.

B. Air is normally bled from the intermediate stage of the engine compressor through the intermediate pressure port and in turn through the intermediate pressure check valve with the check valve (poppet/shaft) in the open position. C. In order to meet air supply requirements at low engine speeds, air is bled from the high stage of the engine compressor. When the higher pressure bleed air enters the bleed air supply duct, the check valve (poppet/shaft) immediately closes due to the delta P between the outlet 14th or 15th stage high pressure air and the 8th stage intermediate pressure air. The check valve (poppet) seals against a fixed seat in the inlet flange thus preventing high pressure bleed flow to the intermediate bleed pressure ports.

2.操作（图2）

A.当条件活门使用时，单向活门位于发动机排气口和供气预冷器之间的中压引气管道中，或位于发动机排气出口和压力调节活门之间。

B.空气通常从发动机压缩机的中间级通过中压端口排出，然后在单向活门（提升阀/轴）处于打开位置的情况下通过单向活门排出。

C.为了满足低发动机转速下的供气要求，从发动机压缩机的高级排出空气。当高压引气进入引气供应管道时，由于出口第14或第15级高压空气和第8级中压空气之间的ΔP，单向活门（提升阀/轴）立即关闭。单向活门（提升阀）密封在入口法兰中的固定阀座上，从而防止高压排放流到中间排放压力端口。

八、工作参数

九、在系统中工作原理

Air Supply Distribution：The air-supply-distribution ducts move supply air to the airplane systems that use the air. Engine ducts , pressure, and temperature control components, provide pressure and temperature controlled air from the engine to the main supply ducts.

供气分配：供气分配管道将供气输送到使用空气的飞机系统。发动机管道、压力和温度控制部件将压力和温度受控的空气从发动机输送到主供气管道。

(1) The intermediate-pressure-check valve is an in-line check valve. The valve is made up of these components:

(a) An outer shell

(b) Inner shell with strut supports

(c) Tube guide

(d) A sliding tube/valve plate assembly.

(2) The valve is installed between the intermediate-pressure manifold and the HP/IP manifold. The valve is found halfway up the right side of the engine. The valve outlet flange is larger than the valve inlet flange. This prevents installation in the wrong direction. An arrow on the body of the valve indicates direction of flow.

(3) When the pressure upstream of the intermediate-check valve becomes greater than that downstream the valve poppet assembly slides open. The tube guide in the inner shell guides the poppet assembly when moving. When the pressure upstream of the intermediate-pressure check valve becomes less than the downstream pressure, the poppet assembly slides closed. This prevents reverse flow through the valve.

（1） 单向活门是一种直列式单向活门。活门由以下部件组成：

（a）外壳

（b）带支柱支撑的内壳

（c）管导向器

（d）滑动管/阀板组件。

（2） 该活门安装在中压歧管和高中压歧管之间。该活门位于发动机右侧的中途。活门出口法兰大于活门入口法兰。这可以防止安装方向错误。活门壳体上的箭头指示流向。

（3） 当单向活门上游的压力大于下游的压力时，提升阀组件滑动打开。内壳中的导管在移动时引导提升阀组件。当中压止回阀上游的压力小于下游压力时，提升阀组件滑动关闭。这可以防止通过活门的逆流。