RS/RR
SUPER PRECISION
AIR REGULATORSSUPER PRECISION
AIR RELAYS■ DESCRIPTION

Servo-balanced system comprising Rolling diaphragm andMeasuring capsule provides exceptionally precise andstable pressure control with constant bleed feature.
Series-RR offers exceptionally precise 1:1 pressure relay
control with ± bias adjustment capability by external pilot
operation.
RS

RR■ FEATURES●

Ultra Accurate and Stable Pressure Regulation :Sensitivity ≦ 0.1 % F.S. Repeatability ≦ ± 0.1 % F.S.

●Extremely Excellent Characteristics : in Relief-, Pressure-,and Flow- sensitivities.
Particularly, minimum relief pressure as low as 3 × 10 -- 5 MPa(theoretical Relief sensitivity) finds best applications in Web tension
controls and Air balancers, etc.

Excellent Start-up Stability :No readjustment of regulated pressure required even after long
"down - time".
● Remote Control of Pressure : ( Series-RR )Advisably used for high precision remote control of pressure.
●●

Adaptable Mounting :Mounts at any angle. Bracket, Panel or Pipe mounted.

■ SPECIFICATIONS
TYPE
TERM

Working Fluid
Set Pressure Range
Supply Pressure Range※1Input Signal Pressure Range

Relief Function※ 2 Repeatability■ OP TION

INTERNAL
PILOT
EXTERNAL
PILOT

RS- 4kPa

14 〜 420kg

Note : ※ 1 Applicable to Series-RR only.
※ 2 F.S. = Full Scale.
※ 3 At Set pressure 0.2MPa■ MODEL DESIGNATION
Example1

R R・H R - 8

14 〜 840(Series RR )( 2 ) Pressure Gauge G :Within 0.1%
0.03 ( Theoretical )130( 1 ) Bias Adjusting Knob BA
Turrning of BA knob effects bias
pressure within the range of± 0.2MPa

IncorporatedWithin ± 0.1%% F.S.

RcRcRR- 8990

※2Pipe Port
Gauge Port
Accessory Parts
WeightR S・H R - 8

Clean Compressed Air
14 〜 840

kPakPaPressure Sensitivity% F.S.
Relief SensitivitykPa�/min (normal)※ 3 Relief Flow Rate�/min (normal)※ 4 Air Consumption
Operating Temperature℃

RS- 8260• Accuracy ± 1.5 % F.S.
• OPT.No. Unit Pressure Range Min.Graduation

Within 3.7
5 〜 60G025 MPa0 〜 0.25

0.005

G060 MPa0 〜 0.6

0.01

RS = 1/8, 1/4, 3/8 ; RR = 1/4, 3/8
1/4 ( Two Ports )Mounting Bracket ( Standard )RS = 0.75, RR ( std. ) = 0.72, RR ( W.Bias knob ) = 0.78

G100 MPa

0〜10.02※ 4 Because of air bleed servo control action,a small amount of air escapes normally intoatmosphere.

LLL■ OUTSIDE DIMENSIONSRSSERIES■ EX PL A NATORY CONSTRUC TION
AND PRINCIPL E OF OPER ATION

Series-RS and Series-RR have the same construction and perform pressure control with thesame operating principle, except that Series-RR can control output pressure with a pilot signal
pressure externally applied.

Series-RS (Internal Pilot)

Series-RR (External Pilot)

PRINCIPLE OF OPERATION ( COMMON TO RS AND RR )・ Series-RS and -RR utilize a servo balanced system in which Supply -and Relief valves are operated by a pilot valve. The pilot valve is opened or closed byexpansion or contraction of a sensitive Measuring capsule.
・The regulated pressure is conducted into Control chamber and surrounds
Capsule, the "heart" of the regulator. Measuring capsule offers extreme stabilityof movement under all operating conditions.
・ A small amount of air flows normally through Pilot valve into Pilot pressurechamber and out through Bleed orifice to atmosphere, assuring the stable pilotpressure.
・ A small change in output pressure will cause Capsule to flex slightly and thus
move Pilot valve, resulting in a substantial change in the Pilot pressure.
・ In turn, this change upsets the force balance of Diaphragm assembly, whichcauses an appropriate movement of either Supply or Relief valve, thus correcting

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any small error in output pressure. Eventually, Capsule and Pilot valve return totheir initial equilibrium positions respectively.
・ The primary reason for the ultra high accuracy is the fact that the movement ofPilot valve, required to effect substantial changes in Supply valve position isextremely small. The high gain of this servomechanism permits desired output
pressure to be maintained with exceptional accuracy and repeatability.
・ Manual adjustment of Control knob provides sensitive setting of output pressure(Series-RS) or bias pressure (Series-RR).
RELAY FUNCTION (FOR SERIES-RR ONLY)
A change in Signal pressure to cause similar flexure of Measuring capsule requires
an exactly equal change in output pressure to return Capsule and Pilot valve totheir equilibrium position. This gives Series-RR its precise 1 : 1 ratio pressure relay
control characteristic with bias adjustment capability by external pilot operation.

RRRR

SERIESSERIES < with Bias Adjustmemt Knob BA >4

RS RRSERIESAPPLICATIONSFUJIKURA'S Super Precision Air Regulators and Air Relays (Series-RS and Series-RR)
are widely used in precision control applications such as :(1) Web Tension Control :Combined with Double - Action Super Cylinder(Model SCD, Ultimate low friction type ) and Electro= Pneumatic Transducer ( Series-RT ).
Printing machine, Paper Processing machine, Plastic Film Processing machine, Textile machine, etc.

(2) Push - down Pressure Control :Combined with Double -Action BF Cylinder (Model FCD) and Electro -Pneumatic Transducer (Series-RT ),Grinding machine, Abrasion Testing machine, Soil Texture Testing machine, Sheet Cutter, etc.

(3) Volume Boosting and Remote Loading :Valve control for instrumented equipment, etc.

(4) Different Settings of Secondary Pressure by Remote Control :(1) Web Tension Control( 2 ) Push-down Pressure Control (Grinder)( 3 ) Volume boosting and remote control( 4 ) Remote-controlled setting of Different pressures( Multiple outputs )< Note >FCD : BF Cylinder ( Standard Cylinder. Cat No. KS -570E )SCD : BF Cylinder ( Super Cylinder. Cat No. KS -570E )R P : Precision Air Regulator ( Cat No. KS -129E )R S : Super Precision Air Regulator ( Cat No. KS -128E )R R : Super Precision Air Relay ( Cat No. KS -128E )RR・HR : Super Precision Air Relay ( High Relief type, Cat No. KS -128E )R T : Precision Electro-Pneumatic Transducer ( Cat No. KS -130E )5

CAUTION
INSTALLATION AND PRECAUTIONSPRECAUTIONS COMMON TO SERIES - RS AND SERIES - RR
햲 Flush out all air lines throughly to remove dirt and scale before
installation is made.
햳 When plumbing connections, apply seal tape onto male threads
starting with 3rd. thread back away from end to avoid possibility ofgetting the tape or sealant into the regulator and air line.
SEAL TAPEYESNOSOLID OR LIQUID SEALYESNO햴 Drain and dirt in supply pressure line will cause malfunction ofRegulator. Be sure an Oil-mist separator together with an Air filter (of 5micron or less) are installed ahead of the regulator in the air line.
햵 Locate a Lubricator, if necessary, downstream beyond the regulator.
햶 Connect supply air to IN port and output to OUT port as marked onbottom of Body.
햷 A slight hissing sound of bleed air is the proof of normal air bleed
servo control action. Should bleed air be blocked shut, remove Bleed
screw and clean Exhaust vent for proper regulating operation.

INSTALLATION ( SERIES - RR ONLY )햲 A change in signal pressure effects a exactly equal change in output
pressure. In the input signal pressure line, use a Pressure regulator
with accuracy suitable for particular application.
햳 Connect input signal pressure pipe line to either one of two pilotpressure pipe ports on the top of Body.
햴 Excessive tightening of Bias adjusting screw may cause failure ofCapsule.

If you have any question or special application need, FUJIKURA are readyto assist you. Please consult us at the address printed on the back cover.

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