(c)
To measure the differential pressure (method 2), do the steps that follow: 1) Connect the tank to the tubing at the inlet fitting. 2) Connect the vacuum source to the valve on the tank. 3) Open the valve on the tank and pull the tank down to a pressure differential of
3.0 in Hg. 4) Close the valve on the tank. Verify that the rate of change of the pressure does
not exceed 0.75 in Hg/min. 5) Disconnect the vacuum source from the tank and open the valve. 6) Disconnect the tank from the inlet fitting. 7) Reconnect the tubing from the sensing inlet to the A forward smoke detector at
the inlet fitting.
(d) To measure the flow rate (method 1), do the steps that follow: 1) Connect vacuum source with rotameter and gage to the exposed bulkhead fitting. 2) Pull a vacuum of 3 + 0.5 inches of mercury. Observe that the leakage does not
exceed 0.05 scfm.
3) Disconnect the vacuum source and reconnect inlet tubing.
(7) Test B Aft Smoke Detector Tubing
(a)
Make sure there is a plug in the sensing point inlet tubes in the air grilles at stations 839 and 879 or 940.
(b)
Disconnect inlet tube to B aft smoke detector from the bulkhead fitting (Detail B, Fig. 501).
(c)
To measure the differential pressure (method 2), do the steps that follow: 1) Connect the tank to the tubing at the inlet fitting. 2) Connect the vacuum source to the valve on the tank. 3) Open the valve on the tank and pull the tank down to a pressure differential of
3.0 in Hg. 4) Close the valve on the tank. Verify that the rate of change of the pressure does
not exceed 0.75 in Hg/min. 5) Disconnect the vacuum source from the tank and open the valve. 6) Disconnect the tank from the inlet fitting. 7) Reconnect the tubing from the sensing inlet to the B aft smoke detector at the
inlet fitting.
(c) To measure the flow rate (method 1), do the steps that follow: 1) Connect vacuum source with rotameter and gage to the exposed bulkhead fitting. 2) Pull a vacuum of 3 + 0.5 inches of mercury. Observe that the leakage does not
exceed 0.05 scfm.
3) Disconnect the vacuum source and reconnect inlet tubing.
(8) Close Up
(a)
Install equipment cooling blower access panel.
(b)
Remove plugs from all eight sensing points.
(c)
Test operation of system with steps A.(2)(e) thru A.(2)(i).
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Feb 20/92 BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details. 26-16-0 Page 507
MAIN CABIN SMOKE DETECTION TUBING - CLEANING/PAINTING
EFFECTIVITY
Passenger/Cargo Convertible Airplanes
1. General
A. This section contains the procedure to clean the smoke detection tubing manifolds in the main cabin.
2. Clean the Smoke Sampling Manifold
A. Standard Tools and Equipment
(1)
Air source - filtered, compressed, 30 psig maximum
(2)
Caps - for the inlet tubes on the detectors
(3)
Mechanical probe
(4)
Tube brush
B. Consumable Materials
(1) Soap and water solution - commercially available
C. References
(1)
26-16-00/501, Lower Cargo Compartment Smoke Detection System
(2)
36-00-00/201, Pneumatic System
D. Procedure
(1)
Remove the pneumatic power (Ref 36-00-00/201).
(2)
Disconnect the sampling manifold from the smoke detectors.
(3)
Install caps on the inlet tubes on the detectors.
(4)
Remove the manifold tees and the applicable weldment assemblies from the manifold.
Apr 01/97 26-16-0 Page 701
BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details.
(5)
Use the soap and water solution and the tube brush to clean the tees and weldment assemblies.
(a)
Flush the tees and weldment assemblies with water.
(b)
Let the tees and weldment assemblies dry.
(6)
Remove all the end caps from the sampling manifold.
(a) Discard the end caps.
(7)
Remove all unwanted material from the ends of the manifold and from the orifices in the manifold.
(8)
Use the mechanical probe to remove all the contamination from the inner wall of the manifold across from the orifices.
(9)
Install the tees in the manifold.
(10)
Apply pressurized air to each manifold at the end farthest from the detectors.
(11)
Make sure the rubber tubing and tubing connectors are not worn or damaged.
(a) If there are cracks, holes, or damage to the tubing or connectors, replace them. 中国航空网 www.aero.cn 航空翻译 www.aviation.cn 本文链接地址：737 AMM 飞机维护手册 防火 FIRE PROTECTION(37)
