KVF. Flow Control Servovalve (FCS) DESCRIPTION FEATURES ORDERING INFORMATION KVF X X X X X. BLN Issued: February 2004

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DESCRIPTION KVF Flow Control Servovalve (FCS) Issued: February 004 The KVF Flow Control Servovalve is a precision servovalve that provides an output flow rate proportional to a low power electrical

It features a torque motor-actuated, double-nozzle flapper pressure control pilot valve mated to a pressure-actuated, spring-centered boost valve module of a unique double-spool configuration.

1 DESCRIPTION KVF Flow Control Servovalve (FCS) Issued: February 004 The KVF Flow Control Servovalve is a precision servovalve that provides an output flow rate proportional to a low power electrical input signal. It features a torque motor-actuated, double-nozzle flapper pressure control pilot valve mated to a pressure-actuated, spring-centered boost valve module of a unique double-spool configuration. The design of this servovalve does not require a centering feedback spring and ball for spool position. The servovalve's pilot stage is a stand-alone, closed loop pressure control valve which uses internal hydraulic pressure reactions to achieve its closed loop control characteristics. This combination was selected to provide fabrication economies resulting in true servovalve performance at proportional valve pricing. The KVF Servovalve's steady state/dynamic response characteristics are compatible with industrial feedback control system applications. FEATURES Self-contained pressure feedback, eliminates requirement for feedback spring and ball for spool position ISO 4406 filtration rating of 8/5 (Nominal 0 micron filtering provides dependable performance) Standard manual operator assists with operation and system diagnostics Requires low power dc current to drive rated flow; ±0 ma, ±40 ma, ±00 ma, ±50 ma, or ±0 ma, are standard options. The ±0 ma, can be driven directly from PLC. Does not require PWM drive for dither but is directly compatible with other drives 4 to 0 ma version is configured such that 4 ma = 0 flow and 0 ma = maximum flow Unique two spool main body design allows for factory adjustment of null pressures at each working port Units available in standard line-to-line or overlapped configuration in all flows from /4 gpm to 0 gpm at no additional cost Installation dimensions common to all servovalves Pricing is independent of flow capability Four connector option: MS, -pin WP, 4-pin WP, or - pin WP Easily connected for unidirectional use from / gpm to 5 gpm at 000 psi rating Adaption maniflods available for conversion to other valve patterns Dual spool design provides added safety shut down if contamination causes failure of either spool Capability of separating control source from main stage supply to accommodate high back pressure applications ORDERING INFORMATION Device Identity Rev Supply Pressure Flow Rating % Lap Split Pilot Stage KVF X X X X X Ordering specifications for standard models. DEVICE IDENTITY The modle code for this device is KVF. MODEL CODE A C D E F G SUPPLY PRESSURE 500 to 000 psi 00 to 000 psi 500 to 000 psi with separate pilot drain 500 to 000 psi 500 to 000 psi w/o cylinder port orifices 500 to 000 psi w/o cylinder port orifices and with pilot drain Danfoss, 0-09 BLN

2 ORDERING INFORMATION (continued) FLOW RATING MODEL CODE FLOW RATING.5 gpm.5 gpm 5 5 gpm 6 0 gpm 7 5 gpm 8 0 gpm 9 0 gpm with 00 lb/in springs PILOT STAGE % LAP SPLIT MODEL CODE % LAP SPLIT 0 Line-to-line 50% Standard overlap, 50% Standard overlap, % Heavy overlap, 50% 4 Heavy overlap, % PILOT STAGE DEVICE NUMBER RATED CURRENT COIL(s) CONNECTOR TYPE SCALE FACTOR 0 * MCV6A0 ±50 ma ohms Packard.5 psid/ma 0 * MCV6A0 ±50 ma ohms MS.5 psid/ma 0 * MCV6A04 ±0 ma 6/9 ohms Packard 0.78 psid/ma 05 * MCV6A07 ±40 ma 69 ohms MS 4. psid/ma 06 MCV6A407 ±40 ma 06 ohms MS 5.5 psid/ma 07 MCV6A40 ±40 ma 06 ohms Packard 5.5 psid/ma 08 * MCV6A0 ±40 ma 69 ohms Packard 4. psid/ma 09 MCV6A50 ±0 ma 64 ohms MS.6 psid/ma 0 * MCV6A0 ±0 ma 6/9 ohms Packard () 0.78 psid/ma 4 MCV6A0 ±00 ma ohms MS.4 psid/ma 5 MCV6A0 ±0 ma 6/9 ohms MS 0.78 psid/ma 6 MCV6A0 ±60 ma 6/9 ohms Packard ().47 psid/ma 7 MCV6A0 ±60 ma 6/9 ohms MS.47 psid/ma *.5,.5, and 5.0 gpm only. TYPICAL APPLICATIONS % of supply pressure at C and C when servo valve is at null. 8 MCV6A0 ±00 ma ohms Packard.4 psid/ma 9 MCV6A50 ±0 ma 64 ohms Packard.6 psid/ma 0 MCV6A4 ±0 ma 6/9 ohms Deutsch 0.78 psid/ma MCV6A00 ±50 ma ohms No connector.5 psid/ma MCV6J407 Special, contact Danfoss MCV6A4 ±60 ma 6/9 ohms Deutsch.47 psid/ma 4 MCV6A5 ±40 ma 69 ohms No connector 4. psid/ma 5 MCV6A6 ±60 ma 6/9 ohms Deutsch.47 psid/ma Air cargo loading Motion simulators Asphalt pavers Saw setworks positioners Concrete pavers Manipulator arms / industrial robots Milling machines Soil stabilizers Material mixing machinery Synchronized knife carriage servodrives Edger in feed board positioners Paper mill machinery Injection molding machinery Platform leveling Edge guide control machinery Product testing machinery Marine deck machinery Rocket motor testing equipment Oil exploration equipment For steering applications, contact Danfoss

3 TECHNICAL DATA Electric current in torque motor coil creates a magnetic torque on armature Armature/flapper rotates about torsion pivot Flapper repositions towards one nozzle, which creates a differential pressure between P and P Each spool moves in the same direction opening the supply )Ps) to output (C or C) on one spool and the output (C or C) to return (PT) on the other spool Differential pressure between P and P causes the spools to move against the centering springs until the spring force balances with the differential pressure As the pressure torque on the flapper becomes equal to the magnetic torque on the armature, the flapper moves away from the closed nozzle to an equilibrium position producing a steady-state control pressure (PC or PC) on the ends of each valve spool Each valve spool stops at a position where the control pressure force on the end of each valve spool equals the spring force on each valve spool Therefore, valve spool position is proportional to input current and, with a constant pressure drop across the spool meter-in and meter-out edges, the flow rate to the load is proportional to spool position Control pressure (PC or PC) reflected to the flapper produces torque on the flapper in opposition to the magnetic torque on the armature DIMENSIONS CAUTION NULL ADJUST ACCESS MANUAL OPERATOR Silicone oil is present and may drip when null is adjusted. Utilize #/ Allen Wrench to adjust. /8 O.D. TUBE FITTING O-RING, PORT PER SAE - J54 9/6-8 UNF ( - PL) PLUGS INSTALLED 84,5 (7.) EXTERNAL PILOT DRAIN ON "D" MODEL ONLY 57,99 (6.). DIA.566 O.D. O-RING (4-PL),4 (.45) C PT C 8,89 (.5) 5,09 9,05 8, (.09) (.75) 4,9 (.50) 55,7 (.8) (.75) 8, (.50) 76, (.00) 99,06 (.90) Dimensions of the KVF in Millimeters (Inches). 48B

4 INTERNAL WORKING SHEMATIC ARMATURE AIR GAP COIL POLE PIECE PIVOT PLATE FLAPPER NOZZLE PT ORIFICE PLATE P P P P P P C C 89C PERFORMANCE RATED SUPPLY PRESSURE 000 psi FLOW RATINGS AT 000 I VALVE DROP.5,.5, 5, 0, 5, 0 gpm RATED INPUT SIGNAL ±0 ma dc, ±40 ma dc, ±00 ma dc, ±50 ma dc, ±0 ma dc, FLUID Petroleum base INTERNAL LEAKAGE (PILOT and BOOST STAGES) <.0 gpm (<.5 gpm available on special models where leakage requirements are primary) THRESHOLD < % rated signal (except for,, and 4 lap) HYSTERESIS < ±5% rated signal LINEARITY < 5% rated signal SYMMETRY 5% (maximum) each direction PRESSURE RISE (BLOCKED OUTPUT PORTS) > 80% Ps at 4% rated signal (except for,, 4 lap) TYPICAL FREQUENCY RESPONSE (000 I VALVE DROP) 90 phase lag frequency > 0 Hz - db amplitude ratio frequency > 0 Hz RETURN PRESSURE Atmospheric to 00 psi ("D" model provides separate return for higher return ratings) FLUID/AIR RATED TEMPERATURE RANGE -0 F to 00 F RECOMMENDED SYSTEM FILTRATION 0 micron (in-line pressure filter) 4

5 LOAD FLOW GPM PERFORMANCE (continued) ELECTRICAL CONNECTION/PHASING Positive voltage at pin B or D with negative voltage at pin A Produces flow out port C SPACE/WEIGHT 7.5 inch high x.8 inch wide x.6 inch long; 6.6 lbs. ENVIRONMENTAL TEMPERATURE NULL SHIFT < 5% rated signal over rated fluid/air temperature range PRESSURE NULL SHIFT < 4% rated signal, 500 psi to rated supply pressure VIBRATION 5 Hz to 000 Hz freguency spectrum g to 46 g's acceleration (varies with frequency) SHOCK 50 g's ( millisecond duration) three mutually perpendicular axes SAND/DUST/HUMIDITY Per MIL-STD-80 current issue FLOW SIZING FORMULAE ( ) P S - P L Q V = Q r i i r 000 Q V is the valve flow at an operating point Q r is the rated flow at i r and P V = 000 psi) i is the operating current i r is the rated current P S is the supply pressure to the valve P L is the load pressure between the valve's control ports (P C - P C ) P V is the valve pressure drop across the valve (P S - P L ) Note: () The rated flow occurs at: P V = P S / (the maximum power transfer to load) () Higher flow rates will incur some saturation () The tank pressure is assumed to be zero (otherwise, substitute P S - P t for P S ) RATED SIGNAL FLOW VS. PRESSURE DROP 40 LOAD FLOW VS. LOAD PRESSURE gpm size 5 gpm size 0 gpm size 5 gpm size.5 gpm size.5 gpm size % -0 LOAD FLOW % - 5% LOAD PRESSURE DROP % SUPPLY % + 50% + 5% + 00% VALVE PRESSURE DROP I - 00% - 75%

6 ADJUSTMENTS The Servovalve is adjustable when re-centering of the output levels is required. The following steps are recommended while referring to the Servovalve drawing (see drawing below). Required tools: one large slotted screw driver & one / internal hex wrench. Locate the neutral adjustment access point. Using the slotted screw driver remove the access screw. See Caution #. See Caution # Insert the hex wrench a short distance into the access opening and engage the adjustment setscrew.. Some applications require observing the system load while adjusting the servovalve and some require observing an electrical deviation meter which measures closed loop feedback errors while adjusting the load. Adjustments are make by turning the hex wrench very slowly either CW or CCW. Most adjustments require less than / turn from the starting point to re-center the servovalve to achieve the desired results. 4. Upon completion ensure that the access screw is reinstalled. See Caution #. Caution # Once the access screw is removed a small amount of silicone fluid may leak form this opening; the amount of leakage depends on the valve orientation (see figure ) in reference to gravity. Ensure that the screw is replaced once the re-centering is completed Caution # To adjust neutral requires operating the hydraulic system; therefore, prior to the actual adjustment, take the necessary safety precautions, such as having unnecessary personnel stand away form the machine as the system load will likely move. Caution #, A small amount of silicone oil leakage is acceptable (approximately 5 % of the total 45 cubic centimeters). If excessive silicone oil is lost, restore the fluid using silicone oil replacing kit K46 for models MCV & KVF. For models MCV0, use kit K45. Do not reuse any silicone oil that leaks from the cover due to the possibility of contamination. NEUTRAL ADJUSTMENT ACCESS MANUAL OPERATOR MAXIMUM/MINIMUM OIL LEVEL ADJUSTMENT NEUTRAL SETSCREW SILICONE OIL LEVEL SERVOVALVE 00 6

7 SERVOVALVE (KVFXXXXXX) O-RING REPLACEMENT Pilot Stage Orifice Boost Item 4 5 Part Number K0080 K0089 K008 K0849 K07006 Qty 6 6 I.D..46 ± ± ± ± ±.005 Dimensions O.D Width Durometer 75 ± 5 75 ± 5 75 ± 5 90 ± 5 70 ± 5 5 Material Viton Viton Viton Viton Nitrile Pilot Stage Bottom Boost Stage Top Boost Stage 04 7

8 Servovalve Manifold Options Use this drawing and the chart listed below to determine servovalve manifold mounting. Top View Side View E A D F B C 0 Danfoss Dimensions in Inches (Millimeters) Part Number A B C D E F K Pilot Pressure Plate (95,5) (66,04) (,4) (8,) (76,) (5,56) Separate PCP Supply & Tank K Pilot Pressure Plate (95,5) (66,04) (,4) (8,) (76,) (5,56) Separate Supply to PCP K Blanking Plate (0,6) (80,0) (9,05) (8,) (76,) (7,6) KK NA NA NA D0 Porting Adapter Plate (0,6) (57,5) (5,4) KK NA NA NA D0 Porting Adapter Plate (07,95) (6,5) (5,4) KK NA NA NA 0.65 Dia. Port Circle Adapter Plate (0,6) (57,5) (,7) KK NA NA NA Dia. Port Circle Adapter Plate (99,06) (50,8) (9,05) KK ±0.06.5± NA NA NA Dia. Port Circle Adapter Plate (07,95) (8,55) (,) KK NA NA NA KVF to V7059 Adapter Plate (0,6) (50,8) (9,05) KK Valve Manifold (5,9) (7,0) (50,8) (05,0) (9,9) (8,5) KK Single Valve Manifold (7,0) (76,) (5,4) (56,9) (07,7) (7,4) KK Valve Manifold (5,4) (7,0) (50,8) (05,0) (8,4) (8,5) KK Valve Manifold (79,4) (7,0) (50,8) (04,9) (55,5) (8,5) KK Valve Manifold (406,4) (7,0) (50,8) (04,9) (8,5) (8,5) SAE Fittings on Sides KK Single Valve Manifold (7,0) (76,) (8,) (6,5) (4,) (7,4) SAE Fittings on Bottom 8

9 CUSTOMER SERVICE NORTH AMERICA ORDER FROM Danfoss (US) Company Customer Service Department 500 Annapolis Lane North Minneapolis, Minnesota Phone: (76) Fax: (76) DEVICE REPAIR EUROPE ORDER FROM Danfoss (Neumünster) GmbH& Co. Order Entry Department Krokamp 5 Postfach 460 D-45 Neumünster Germany Phone: Fax: For devices in need of repair or evaluation, include a description of the problem and what work you believe needs to be done, along with your name, address and telephone number. RETURN TO Danfoss (US) Company Return Goods Department 500 Annapolis Lane North Minneapolis, Minnesota

MCV102A. Pressure Control Servovalve DESCRIPTION FEATURES ORDERING INFORMATION. BLN Issued: October 1998

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