Maintenance Manual
Excess Flow Servo F576 Series
Meggitt Fuelling Products Maintenance Manual
Excess Flow Servo – F576 Series
LIST OF EFFECTIVE PAGES On a revised page, the portion of text or illustrations affected by the change is indicated by a vertical line in the outer margin of the page. When a revision is issued, the entire document is reissued with the current revision number and date shown on all pages. For major revisions, the basic number is incremented. For minor revisions, the number following the decimal is incremented. Dates of issue for original and subsequent revisions are as follows: Original 1.0 12/15/2004 Revision 1.1 02/01/2006 The total number of pages in this technical document is 21 consisting of the following: Title, 2 – 21
TABLE OF CONTENTS
SUBJECT
PAGE
Introduction Description and Operation Fault Isolation Disassembly Cleaning Inspection Repair Assembly Adjustment Illustrated Parts List
3 3 7 9 10 11 12 13 14 17
Meggitt Fuelling Products Maintenance Manual
Excess Flow Servo – F576 Series
INTRODUCTION 1. General This manual provides component maintenance shop instructions for the Excess Flow Servo (servo). 2. Revision Service This manual will be revised as necessary to show the current information. 3. Weights and Measurements Weights and measurements in this manual are expressed in both English (U.S. customary) and selected Metric (SI) units.
DESCRIPTION AND OPERATION 1. Description The Excess Flow Servo (servo) (see Figure 1) provides the means of automatically and rapidly closing the hydrant valve in the event of a burst hose or similar emergency. 2. Operation (See Figure 2) A. When an excess flow servo is installed, the actuation air is supplied from the excess flow pilot air port. The 1/4-inch dry-break quick disconnect connects directly to the excess flow servo. As long as the sense pressure is low, the control poppet remains open, allowing more fuel to bleed downstream than enters through the fixed upstream orifice, allowing the piston to open. As the sense pressure approaches the control pressure, the control poppet closes, balancing the flows in and out of the hydrant valve piston cavity. The piston position is thereby controlled to maintain the preset control pressure.
Meggitt Fuelling Products Maintenance Manual
Excess Flow Servo – F576 Series
B. Should there be a sudden increase in downstream sense pressure, the fast closing poppet will open, allowing upstream pressure to flow rapidly into the main piston cavity. This will close the hydrant valve rapidly. C. Following an excess flow trip, operator action is required to manually reset the servo by rotating the reset arm. 3. Leading Particulars (Refer to Table 1) 4. Model Variations Refer to Table 2 for the available F576 series servo variations.
Table 1. Leading Particulars Service Automotive and Aviation Fuels Operating Pressure (maximum) 200 psi (13,6 bar) Fluid Temperature –40 to 165°F (–54 to 74°C) Ambient Temperature –40 to 165°F (–54 to 74°C)
Table 2. Excess Flow Servo Variations SERVO MOD LETTERS
Basic B E F G
DESCRIPTION
Ductliron body and single point connection to mate with F555 or F571 socket. Provides single flow setting and product selection Adds dual-flow setting selector Removes product selection pin Replaces single point connection with ¼-inch ANPT port Changes body to aluminum alloy
Meggitt Fuelling Products Maintenance Manual
Excess Flow Servo – F576 Series
FAULT ISOLATION 1. General A. Examine the servo to verify completeness of assembly, cleanliness, correct identification, and that no obvious damage is evident. B. Visually verify that all markings and nomenclature are complete and legible. C. Refer to Table 3 for fault isolation information. Locate suspected faulty component and take appropriate remedial action. D. All normal rules and procedures associated with good safety practices during performance of fault isolation must be observed and implemented at all times.
Table 3. Fault Isolation FAULT
Hydrant valve will not open
POSSIBLE CAUSE
CORRECTIVE ACTION
Insufficient air pressure
Check for the correct pressure at the servo AIR port. Remove the blockage. Cycle the valve to remove the contamination. Remove the servo and service the hydrant valve. Overhaul the servo.
Fuel sense line blocked Hydrant valve seat contaminated or damaged
Hydrant valve is partially open and will not regulate
Poppets jammed by contamination Hydrant valve seat contaminated or damaged
Cycle the valve to remove the contamination. Remove the servo and service the hydrant valve. Service the hydrant valve. Overhaul the servo.
Hydrant valve contaminated Poppets jammed by contamination
Meggitt Fuelling Products Maintenance Manual
Excess Flow Servo – F576 Series
Table 3. Fault Isolation (continue) FAULT
POSSIBLE CAUSE
CORRECTIVE ACTION
Hydrant valve opens but regulated pressure is high Hydrant valve opens but regulated pressure is low
Fuel sense line leakage
Locate and repair the leak.
Insufficient pump pressure
Check pump capacity.
Air-to-fuel or fuel to air contamination
Worn or damaged packings or seals Other contamination sources in system Mounting screws loose
Overhaul the servo.
Leakage at servo/hydrant valve interface
Servo will not operate
Check and correct as necessary. Tighten the screws evenly and securely. Replace the packings.
Damaged or missing packings Incorrectly installed packings Damaged spring or piston
Replace the packings. Overhaul the servo. Replace the damaged parts.
DISASSEMBLY 1. Replacement Parts Kits Refer to the IPL section for information on the replacement parts kits. 2. Disassembling the Servo (Refer to IPL Figure 1) A. Remove the screw (2) and the selector (3) from the servo body (44). Remove the packing (4) from the servo body. If replacement is necessary, remove the pin (1) from the selector.
Meggitt Fuelling Products Maintenance Manual
Excess Flow Servo – F576 Series
B. Remove the plug (6) from the servo body (44). Remove the packings (5), the seat (7), the poppet (8) and the packing (9). NOTE: The pin (25), the hub (26), the shaft (29), the nut (36) and the setscrew (37) are used only on early production servos. C. Remove the screws (22) and separate the cover (23) and the shaft (45 or 29) and associated parts from the servo body (44). D. Remove the screw (19), the washer (20), the reset arm (21) and the washer (24) from the shaft (45) or the hub (26). E. Remove the lower pivot (35) and the arm (38) from the shaft (45) or the hub (26). Remove the setscrew (37) and the nut (36) from the arm. F. Remove the caps (33), the spring (34), the upper pivot (32), the button (31) and the retaining ring (30) from the servo body (44). G. Remove the venturi (12), the packings (10 and 13) from the servo body (44). H. Remove the piston (16) from the servo body (44). Remove the cap (14), the packing (15), the piston shuttle screw (17) and the spacer (18) from the piston. I. If replacement is necessary, remove the pin (11) from the servo body (44).
Meggitt Fuelling Products Maintenance Manual
Excess Flow Servo – F576 Series
CLEANING 1. Cleaning Materials Refer to Table 4 for recommended cleaning materials. Suitable equivalent cleaning materials may be substituted for the items listed.
Table 4. Recommended Cleaning Materials DESCRIPTION
Brush, Bristle, stiff, nonmetallic Dry Cleaning Solvent Pick, Teflon Plastic Bags Tissues, lint-free
SPECIFICATION
SOURCE
– – P-D-680, Type 2 – – – – – –
Commercially available Commercially available Commercially available Commercially available Commercially available
2. Cleaning Procedures WARNING: DRY CLEANING SOLVENT IS FLAMMABLE AND TOXIC TO EYES, SKIN, AND RESPIRATORY TRACT. SKIN/EYE PROTECTION REQUIRED. AVOID REPEATED/PROLONGED CONTACT. USE ONLY IN WELL VENTILATED AREAS. GOOD GENERAL VENTILATION IS NORMALLY ADEQUATE. KEEP AWAY FROM OPEN FLAMES OR OTHER IGNITION SOURCES. A. Clean all metal parts by washing thoroughly in dry cleaning solvent. Remove stubborn deposits by scrubbing with a nonmetallic stiff bristle brush. Use a Teflon pick to remove obstructions from ports, grooves and passages. NOTE: All of the parts must be free of corrosion, dirt, grease, oil, or any other foreign matter. WARNING: WEAR EYE PROTECTION WHEN DRYING PARTS WITH COMPRESSED AIR. DO NOT DIRECT AIRSTREAM AT PERSONNEL OR LIGHT METAL PARTS.
Meggitt Fuelling Products Maintenance Manual
Excess Flow Servo – F576 Series
B. Dry parts with clean lint-free tissues or clean, dry compressed air. C. Package clean parts in plastic bags.
INSPECTION 1. General A. Under strong light and magnification, visually check all parts in accordance with the general criteria specified in paragraph 2 below. B. Repair minor damage in accordance with local standard procedures. If damage is major or beyond simple repair, replace the part rather than attempt any extensive repairs. 2. Component Checks (Refer to Table 5)
Table 5. Component Checks DESCRIPTION (IPL Figure 1 Item No.)
General
Piston (16)
Compression Spring (34)
CHECK CRITERIA
1) Visually check all parts as applicable for nicks, cracks, cuts, burrs, corrosion, breaks, scoring, deformation, dents, thread damage, or any other obvious defects. 2) Make sure that the ports, passages, recesses and sealing grooves are clean and unobstructed. 3) Check all sealing and seating surfaces for damage or corrosion which would affect sealing. 1) Replace the piston if there is scoring on the outside diameters of the piston body. 2) Replace the piston if bare metal shows through the anodized surface. Check for: 1) Deformation or permanent set. 2) Free length of approximately 0.932 inch (23,7 mm).
Meggitt Fuelling Products Maintenance Manual
Excess Flow Servo – F576 Series
Table 5. Component Checks (continue) DESCRIPTION
CHECK CRITERIA
(IPL Figure 1 Item No.)
Servo Body (44) (stainless steel)
Servo Body (44) (aluminum alloy)
Check for: 1) Scoring on the inside diameters of the bores. 2) Damage to the seating surfaces. 3) Raised burrs on the seating surface for the hydrant valve. The surface must be flat (may be repaired). 4) Scoring on the seal groove surfaces for the packings. Minor damage may be repaired. Replace the body if there is extensive scoring, corrosion, or other damage. Check for: 1) Scoring on the inside diameters of the bores. 2) Damage to the seating surfaces. 3) Raised burrs on the seating surface for the hydrant valve. The surface must be flat (may be repaired). 4) Scoring on the seal groove surfaces for the packings. Replace the body if bare metal shows through the anodized surface. Replace the body if there is extensive scoring, corrosion, or other damage.
Meggitt Fuelling Products Maintenance Manual
Excess Flow Servo – F576 Series
REPAIR 1. General Repairs normally will consist of replacing damaged or malfunctioning parts with new parts, however, this section outlines minor repair procedures permissible for component parts, and specifies mandatory replacement parts. 2. Repair Materials Refer to Table 6 for recommended repair materials. Suitable equivalent repair materials may be substituted for the items listed
Table 6. Recommended Repair Materials DESCRIPTION
Cloth, Abrasive, Crocus, 600-grit
SPECIFICATION
SOURCE
P-C-458
Commercially available
3. Repair or Replacement A. Replace all parts which are obviously cracked, worn, deformed, damaged beyond repair, or which do not meet check requirements and cannot be restored to serviceable condition by allowable repair. B. Polish out minor corrosion and surface damage on stainless steel parts with crocus abrasive cloth. C. Polish out minor scoring on piston (16) with crocus abrasive cloth. D. After polishing, re-clean parts as specified in the CLEANING section. E. Clear minor thread damage with a thread restoring tool; replace all threaded components having crossed or stripped threads.
Meggitt Fuelling Products Maintenance Manual
Excess Flow Servo – F576 Series
ASSEMBLY 1. Replacement Parts Refer to the IPL section for information on the replacement parts kits. 2. Assembly Materials Refer to Table 7 for recommended assembly materials. Suitable equivalent materials may be substituted for the items listed. 3. Lubrication Prior to assembly, LIGHTLY lubricate all of the packings and seals with silicone grease (DC1292) . Table 7. Recommended Assembly Materials DESCRIPTION
Masking Tape Silicone Grease
SPECIFICATION
– DC1292
SOURCE
Commercially available Dow Corning Corporation (V71984) 2200 West Salzburg Road Auburn, Michigan 48611 Voice Telephone: 517-496-4388 Fax Telephone: 517-496-5324
4. Assembling the Servo (Refer to IPL Figure 1) A. If removed, install the pin (11) in the servo body (44). Make sure that the pin is fully seated in its bore.
Meggitt Fuelling Products Maintenance Manual
Excess Flow Servo – F576 Series
B. Install the spacer (18) and the piston shuttle screw (17) in the piston (16). Install the packing (15) and the cap strip (14) in the seal groove of the piston. Install the piston in the servo body (44). C. Install the venturi (12) and the packings (10 and 13) on the servo body (44). Retain the parts with masking tape. D. Install the button (31), the upper pivot (32) and the retaining ring (30) in the servo body (44). NOTE: The pin (25), the hub (26), the shaft (29), the nut (36) and the setscrew (37) are used only on early production servos. E. If equipped, install the setscrew (37) and the nut (36) in the arm (38). Install the lower pivot (35) and the arm on the shaft (45) or the hub (26). F. Install the cover (23), the washer (24) and the reset arm (21) on the shaft (45) or the hub (26). Install the screw (19) and the washer (20) to secure the reset arm. G. Install the spring (34), the spring caps (33), the shaft (45 or 29) and associated parts, and the cover (23) on the servo body (44). Secure the cover with the screws (22) . H. Install the packing (9), the poppet (8), the seat (7), the packings (5), and the plug (6) in the servo body (44). I. Install the packing (4) in the packing groove of the selector (3). Install the selector on the servo body (44) and secure it with the screw (2). Install the pin (1) in the selector.
Meggitt Fuelling Products Maintenance Manual
Excess Flow Servo – F576 Series
ADJUSTMENT 1. Adjustment Setup A. Install the hydrant valve in an adjustment setup as shown in Figure 3. The hydrant valve should be on a flanged riser, connected to a suitable hydrant servicing vehicle and a fuel receiver tank.
B. The riser supply must have pressure and flow capacity to provide 1300 gpm (for F368) or 1100 gpm (for F372) through the hydrant servicer to the receiver tank. C. There must be a manually operated valve between the hydrant servicer and the receiver tank for flow control. A pressure gage at the connecting hose adapter(s) upstream of the flow control valve is recommended. An accurate flow rate meter is required (counting gallons timing with a stopwatch is ineffective due to the rapid change in flow rates as the system valves open). D. The hydrant valve (F368 or F372) must be set up correctly for pressure control and opening time before setting the excess flow servo. 2. Factory Settings for Excess Flow Trip F368 hydrant valve with single-flow F576 1100 (±75) gpm F368C hydrant valve with dual-flow F576B High flow 1100 (±75) gpm Low flow 700 (±75) gpm
Meggitt Fuelling Products Maintenance Manual
Excess Flow Servo – F576 Series
F372 hydrant valve with single-flow F576 700 (±75) gpm F372C hydrant valve with dual-flow F576B High flow 900 (±75) gpm Low flow 700 (±75) gpm Different flow rates may be used if desired, with the following limitations: A. The maximum setting must not exceed 1200 gpm. B. The minimum setting should not be less than 600 gpm. C. The difference between the High and Low flow trips should not be less than 200 gpm. NOTE: Pressure surges in the supply line may cause premature tripping of the excess flow servo. 3. Dual-Flow Servo Operation (Refer to Figure 4) A. High Flow The lever (41) is positioned so that the setscrew (40) rests on the button (31), and is held in place by the F571 socket. B. Low Flow The lever (41) is rotated away and clear of the button (31). 4. Adjustment Procedure A. With the excess flow reset arm (21) held by a restraint in its OPEN position, start the fuel flow using the deadman handle. B. Adjust the flow control valve to set the system flow rate to the excess flow trip point plus (+) 100/150 gpm.
Meggitt Fuelling Products Maintenance Manual
Excess Flow Servo – F576 Series
C. Using the deadman handle, stop the fuel flow. D. Remove the restraint from the excess flow reset arm. E. Using the deadman handle, start the fuel flow. F. Note the flow rate at which the excess flow servo closes the hydrant valve. G. Actuate the excess flow reset arm (21) to reset the servo. H. Repeat steps A through G at least two more times. Calculate the average excess flow trip point. I. If the servo will not trip, or the excess flow trip point is not as required, adjust the servo as follows: 1) To adjust a single-flow servo, or the Low flow on a dual-flow servo: CAUTION: WHEN ADJUSTING THE UPPER PIVOT, HOLD THE BUTTON (31) WITH A BACKUP WRENCH TO PREVENT ROTATION. ROTATION OF THE BUTTON MAY CAUSE ITS RETAINING RING TO COME OFF. Using a 1/8-inch hex key, turn the upper pivot (32) (inside of the button (31)). Turn the pivot inward (clockwise) to increase the trip point. Turn the pivot outward (counterclockwise) to decrease the trip point. 2) To adjust the High flow on a dual-flow servo: NOTE: On a dual-flow servo, the Low flow MUST be adjusted first. Using a 1/8-inch hex key, turn the setscrew (40) (in the lever (41)). Turn the setscrew inward (clockwise) to increase the trip point. Turn the setscrew outward (counterclockwise) to decrease the trip point. 3) Following adjustment, repeat steps A through H above, to check the settings. If necessary, repeat the adjustments until the settings are correct.
Meggitt Fuelling Products Maintenance Manual
Excess Flow Servo – F576 Series
J. Actuate the excess flow reset arm (21) to reset the servo. K. Using the deadman handle, start the fuel flow. L. Adjust the flow control valve to set the system flow rate to the excess flow trip point minus (–) 100/150 gpm. The excess flow servo must not trip. NOTE: Pressure surges in the supply line may cause premature tripping of the excess flow servo.
ILLUSTRATED PARTS LIST
1. General This section lists, describes, and illustrates all detail parts required for maintenance support of the Excess Flow Servo. 2. Scope of Information A. The parts list is arranged in the general order of disassembly. The listing is indented to show the relationship between each part and its next higher assembly. Item numbers used in the parts list are keyed to the corresponding numbers of the accompanying illustration. B. MODIFICATION CODE The modification code indicates the parts usage with respect to the end item. When the MODIFICATION CODE column is blank, the part usage is applicable to all versions unless otherwise specified in the DESCRIPTION column. C. How to Identify a Part 1) When the part number is known: Refer to the parts list for the item number, description, modification codes, and quantity. Refer to the illustration to verify the physical appearance and location of the part.
Meggitt Fuelling Products Maintenance Manual
Excess Flow Servo – F576 Series
2) When the part number is not known: Review the illustrations to identify the part by physical appearance and location. Refer to the accompanying parts list to obtain the part number, description, modification codes, and quantity. D. Abbreviations ASSY FIG. IPL MOD
Assembly. Figure. Illustrated Parts List. Modification.
Meggitt Fuelling Products Maintenance Manual
Excess Flow Servo – F576 Series
IG.
DESCRIPTION
MOD
UNITS
1234567
CODES
PER ASSY
PART NUMBER
ITEM
1 1
F576 125-0500HCP
2
CMS16996-14
3
CMS16996-10 2691498
SERVO, EXCESS FLOW ∙ PIN, SPIROL (Not used with Mods E and F) Product Selection Pin: Position A Turbine Fuel Position B Avgas Position C Miscellaneous Position F Turbine Fuel B Position G Bonded Fuel ∙ SCREW, SOCKET HEAD CAP (Not used with Mod E) ∙ SCREW, SOCKET HEAD CAP ∙ SELECTOR, PRODUCT (Not used with
CMS29513-014 CMS29513-013 2691497 2681936 2681938 2793007-101 CMS29513-029 CMS16562-211 2681848 CMS29513-030 S11338-119 CMS29513-119 2681941 2681939
Mod F) ∙ PACKING, PREFORMED ∙ PACKING, PREFORMED ∙ PLUG (Not used with Mod F) ∙ SEAT (Nylon) ∙ POPPET ∙ PACKING, PREFORMED ∙ PACKING, PREFORMED ∙ PIN, SPRING ∙ VENTURI ∙ PACKING, PREFORMED ∙ STRIP, CAP ∙ PACKING, PREFORMED ∙ PISTON ∙ SCREW, PISTON SHUTTLE
4 5 6 7 8 9 10 11 12 13 14 15 16 17
REF 1
2 F
2 1
1 2 1 1 1 1 1 1 1 1 1 1 1 1
Meggitt Fuelling Products Maintenance Manual
Excess Flow Servo – F576 Series
FIG. ITEM
18 19 20 21 22 23 24 25 26 27 28 29 30 31 1 32 33 34 35 36 37 38 39 40 41 42
DESCRIPTION
MOD
UNITS
1234567
CODES
PER ASSY
PART NUMBER
2681935 CAN500D8-8 CAN935C8 2681970 NK500D8-6M LP500D8-6 2681949 2681999 2681998 2681931 2661058BD010 2661058BD009 2681930 5103-31H 2682000 2681942 2851002-101 2681944 2681940 CMS35649-264 ? CAN565E6H8 ? 2681943-2 2681943-3 2681994 LP565F524H10 2681993-2 2682047
∙ SPACER ∙ SCREW, MACHINE ∙ WASHER, LOCK ∙ ARM, RESET ∙ SCREW, SELF-LOCKING ∙ SCREW, SELF-LOCKING (Alternate) ∙ COVER ∙ WASHER ∙ PIN (Old style) ∙ HUB (Old style) ∙ PACKING, PREFORMED ∙ PACKING, PREFORMED ∙ SHAFT (Old style) ∙ RING, RETAINING ∙ BUTTON ∙ PIVOT, UPPER ∙ CAP, SPRING ∙ SPRING, COMPRESSION ∙ PIVOT, LOWER ∙ NUT, JAM (Old Style) ∙ SETSCREW (Adjustment) (Old style) ∙ ARM, ACTUATING (Steel) ∙ ARM, ACTUATING (Aluminum alloy) ∙ PLUG ∙ SETSCREW ∙ LEVER ∙ BOLT, SHOULDERED
G F B B B
1 1 1 1 3 3 1 1 1 1 1 1 1 1 1 1 2 1 1 1 1 1 1 1 1 1 1
Meggitt Fuelling Products Maintenance Manual
Excess Flow Servo – F576 Series
FIG. ITEM
43 44 45
DESCRIPTION
MOD
UNITS
1234567
CODES
PER ASSY
B
1 1 1 1
PART NUMBER
CAN960-516L 2681929-2 2681929-3 2841000
∙ WASHER, FLAT ∙ BODY, SERVO (Ductliron) ∙ BODY, SERVO (Aluminum alloy) ∙ SHAFT, ACTUATING
G
SERVO REPAIR PARTS KITS AVAILABLE KIT PART NUMBER
DESCRIPTION
ITEMS IN KIT (IPL Figure 1)
KITF576-101
Overhaul
1, 4, 5, 9, 10, 13, 14, 27, 28, 30
