DIAPHRAGMACTUATED VALVES

	DIAPHRAGM ACTUATED VALVES	RAF MODELS	RAF General Information
\| Description \| Applications \| Available Models \| Installation \| \| Typical Application \| Specification Form \| Animation \|	RAF 40 Altitude Control Hydraulic Valve

Description RAF 40 is used to maintain a preset water level of reservoir or water tank in a simple manner. The RAF valve is activated by line pressure. The RAF 40 stays open as long as the water level of the reservoir is below a preset level. As the water level rises the RAF 40 gradually closes. Three adjustable altitude ranges are provided.	Applications Use RAF 40 for reservoirs & water tanks level control anywhere. Line pressure provides energy suitable for operation. RAF 40 is particularly suitable for remote sites. Due to its simple design it is virtually maintenance free. Available Models RAF 40 - General application Altitude Control Hydraulic Valve. Altitude ranges : 15m, 25m & 40m.
Installation RAF 40 Altitude Control Valve is activated by line pressure & controlled by a two- way pilot valve. The actual level head is amplified by a spring loaded mambrane within the pilot. When the pilot’s mambrane is biased by the pressure head, the RAF 40 is piloted to close by the line pressure. Two-way configuration: The valve control chamber drain to the downstream end. The mambrane moves gradually upward. There is no water spill.
RAF 40 - control mode Manual Operation: Open the RAF 40 by closing cocks 1 & 2 & opening the vent. Close the RAF 40 by closing cock 2 & vent & opening cock 1. Automatic Operation: Under normal conditions, when the water level in the reservoir is lower than the ultimate altitude, the RAF 40 is open, as shown. The line pressure flows from the upstream through the pilot & drains downstream. The RAF’s control chamber drains downstream as well. When the water level rises, so does the pressure head under the pilot’s mambrane. When the water reaches its highest level, the pressure overcome the pilot’s spring. The pilot’s mambrane moves upward & closes port 2. The RAF 40 is closed completely, due to the line pressure. When the water level drops, the pilot opens again. It is important to adjust the needle valve to get a gradual closing of the RAF 40 valve.		RAF 40 Altitude Hydraulic Valve Typical Application RAF 40 Altitude Control Valve controls the water level in a water tank.
Adjustment Adjust the needle valve for gentle closing. Adjust the desired altitude within the allowable range using the adjustment screw. Turn the screw counter- clockwise to lower the control altitude.

Standard RAF 40	Altitude Control Range	Special Features
Complete basic RAF valve as specified above		Enamel/epoxy coating
Self-cleaning screen filter		External heavy duty screen filter
Altitude Metal Pilot	Up to 15m, 25m,or 40m	-
Cock valve		-
Needle valve		-
3/8" Reinforced Plastic tubing		Copper or stainless steel tubes

Metal Pilot
Body & bonnet- Bronze Spring-Music wire. Diaphragm-Nylon fabric reinforced Natural Rubber. Bolts & nuts-Zinc plated steel. Pressure rating: up to 16 bar Selection of Springs according to the altitude control range.