Ola Energy Ethiopia Bole Aviation Site Specific Procedures for Pressure Control Checks and Tests PDF

**OLA ENERGY ETHIOPIA** **BOLE AVIATION** Logo, company name Description automatically generated Specific Procedures for Pressure Control Checks and Tests Contents {#contents.TOCHeading} ======== [**1.** **HOSE END PRESSURE CONTROL VALVE (HEPCV) TEST** 3](#_Toc102682695) [**1.1** **TEST ARRANG...

**OLA ENERGY ETHIOPIA** **BOLE AVIATION** Logo, company name Description automatically generated Specific Procedures for Pressure Control Checks and Tests Contents {#contents.TOCHeading} ======== [**1.** **HOSE END PRESSURE CONTROL VALVE (HEPCV) TEST** 3](#_Toc102682695) [**1.1** **TEST ARRANGEMENTS** 3](#test-arrangements) [**1.2** **PRELIMINARY CHECKS** 4](#preliminary-checks) [**1.3** **HOSE END PRESSURE CONTROL VALVE (HEPCV) TEST -- PROCEDURE** 4](#hose-end-pressure-control-valve-hepcv-test-procedure) [**2.** **IN-LINE PRESSURE CONTROL VALVE (ILPCV)** 7](#in-line-pressure-control-valve-ilpcv) [**2.1** **IN-LINE PRESSURE CONTROL VALVE (ILPCV) -- PROCEDURE** 7](#in-line-pressure-control-valve-ilpcv-procedure) [**3.** **CHECK VENTURI (COMMISSIONING & TROUBLE SHOOTING ONLY)** 9](#check-venturi-commissioning-trouble-shooting-only) [**3.1** **VENTURI SET-UP AND VALIDATION CHECKS** 9](#venturi-set-up-and-validation-checks) [**3.2** **CHECK VENTURI (COMMISSIONING & TROUBLESHOOTING ONLY) PROCEDURES** 10](#check-venturi-commissioning-troubleshooting-only-procedures) [**4.** **DEADMAN CONTROL** 11](#deadman-control) [**5.** **LEAK CHECKS AND END OF TEST CHECK** 13](#leak-checks-and-end-of-test-check) [**6.** **INTERPRETATION OF RESULTS AND PROBLEM SOLVING** 13](#interpretation-of-results-and-problem-solving) 1. **HOSE END PRESSURE CONTROL VALVE (HEPCV) TEST** ================================================ 1. **TEST ARRANGEMENTS** ---------------------  **PRELIMINARY CHECKS** ---------------------- Prior to conducting the pressure control test consider the following: - The vehicle availability - Customer refuelling demands - Correct tank / valve sequencing - Check the ullage (space available) of the receiving tank / tanker - Check for correct service tank - Other maintenance / operational activities at the facility - Cannot open hose end coupler handle when disconnected. When coupler connected and open cannot disconnect hose end coupler with handle open. - No leaks from all connections including test pressure gauge point. - Close any thermal relief bypass routes around the test rig valve(s). - No loose, broken or missing components. Check hose end controller has breather correctly fitted. Check hose is free of defects, cuts, abrasion showing nylon reinforcing, blisters and soft pots. - Test rig gauge(s) fit for service and within calibration period. *NOTE: Never use prover tank for conducting pressure control test* **Recommendation:** - All scheduled vehicle periodic checks (weekly, and monthly, quarterly) should be scheduled prior to running this test. Vehicle should be in good condition and free from defects. 3. **HOSE END PRESSURE CONTROL VALVE (HEPCV) TEST -- PROCEDURE** ------------------------------------------------------------- **Step 1 Preparation test** - Bond the equipment and attach the lanyard to the hydrant pit valve if appropriate. - Break seal/unlock and raise the air reference pressure/fuel sense on the secondary system to 6.9 bar (100 psi) or maximum setting if less. - Connect a single hose for product flow and block out the hose end control valve. - Establish maximum flow and then slowly close the test rig valve over 10 to 15 seconds. Note the pressure at zero flow. - The test pressure should be at least 4.8 bar (70 psi) for an optimum test of the various pressure control systems. Where 4.8 bar (70 psi) cannot be achieved then the site shall investigate before continuing with the test. Where the investigation confirms 4.8 bar (70 psi) can never be achieved then the maximum achievable pressure shall be recorded, and the test performed. - Remove a block out unit from HEPCV device and reset air reference pressure to normal setting. **Step 2 Testing the primary pressure control system, the HEPCV pressure control.** - To test HEPCVs, the secondary control system must be deactivated. - Before deactivating the Secondary System, record the reading on air controls pressure gauge. - Break seal/unlock and raise the air reference pressure/fuel sense on the secondary system to 6.9 bar (100 psi) or maximum setting if less. - For non-air reference systems adjust pressure control valve to maximum setting. For dual HEPCV systems proceed to Step 3. - For compensated (Venturi) ILPCV systems, increase the air reference pressure to 6.9 bar (100 psi). **Step 3 Testing For HEPCV surge control** If more than one hose is connected, ensure all poppet handles are closed, then for each HEPCV in turn: - Open the poppet handle and fully open the test rig valves to establish full flow, and record flow rate. - Adjust the test rig ball valve to the point at where the test rig reference gauge pressure begins to rise which will indicate the HEPCV is beginning to control the flow rate or a back pressure of at least 2bar (30psi) is indicated on the test rig gauge. - Close the test rig ball valve smoothly in 2 seconds to stop flow completely. - Record the peak pressure (surge) indicated briefly on test rig reference gauge. This should not exceed 8.3 bar (120 psi). - Open the test rig ball fully to release the locked in pressure. **Step 4 Testing the HEPCVs for pressure control** - When flow has stabilized, slowly close the gate valve on the test rig over a period of about 30 seconds. Note the maximum observed control pressure during the closure from the test rig manifold gauge typically occurring at about 5% of full flow and record the result. - For consistent results, keep closing the gate valve to adjust the flow rate. Do not adjust by opening and closing. - The pressure indicated on the test rig reference gauge should not exceed 3.5 bar (50 psi) during closure except at very low flow rates (just before shut down) where pressures between 3.5 bar (50 psi) and 3.8 bar (55 psi) are normal. - The HEPCV should control pressure smoothly over the closure. Any unusual pressure fluctuation shall be investigated. **Step 5** - At shutdown, the test rig ball valve should also be closed. - With the test rig valve fully closed, observe final pressure on test rig gauge and record the result. - The pressure test rig reference gauge should not exceed 3.8 bar (55 psi). **Step 6 Testing for HEPCV leakage** - After waiting for 30 seconds, record the test rig reference gauge again. - An increase in pressure at no flow conditions is known as pressure creep and indicates that the HEPCV seals may be faulty. - The maximum allowable pressure creep is 0.35 bar (5 psi). - If the results are outside the specified limits at any stage, the test should be repeated. If the repeat tests confirm the original results they should be discussed with the supervisor and appropriate adjustments and retest made or unit replaced. **Step 7** - Shutdown operation and relieve any locked in pressure by opening test rig ball valve - Repeat steps (2) to (6) for each HEPCV **Step 8** - Finally, prior to proceeding to ILPCV tests, if the air reference pressure has been increased, reduce it to the normal level and lock/seal it to protect it against subsequent alteration by unauthorized personnel. **Step 9** - Complete the documentation. If any HEPCV exceeds the specified limits replace with a properly functioning unit. - Record any changes and adjustments that were made to the HEPCVs. **IN-LINE PRESSURE CONTROL VALVE (ILPCV)** ========================================== - This test needs to be done only once per ILPCV for each vehicle to ensure that pressure is controlled over the full range of flow rates from maximum achievable flow to shutdown. - Each venturi/hose combination should be tested separately beginning with the highest flow rate system (e.g., deck hoses). - If the air reference pressure is altered during the test, it must be re-locked/sealed to protect it against subsequent alteration by unauthorized personnel. - The objective is to check that whilst underwing refuelling, the ILPCV is able to protect the aircraft tank from damage by limiting the delivery pressure even if the HEPCV does not function correctly. 4. **IN-LINE PRESSURE CONTROL VALVE (ILPCV) -- PROCEDURE** ------------------------------------------------------- **Step 1** - Ensure that the air reference pressure is at normal operating level. - Select an ILPCV, activate all appropriate nozzles downstream and open relevant test rig valves. Normally there is only one ILPCV so select the set of nozzles that would give the highest flow rate -- probably the deck hose nozzles deployed together. **Step 2** - To test the ILPCV the Primary control system shall be deactivated. To achieve this the HEPCVs are either: - Blocked out by using a hose type block out device. - Blocked out by using a by-pass connection. - Stow other hoses not in use. **Step 3** - Fully open the test rig valves and establish maximum vehicle flow rate available at full vehicle pump speed or maximum hydrant pressure as applicable and record maximum flow rate achieved. **Step 4** - Record the ILPCV hydrant inlet pressure gauge (P.1). - This pressure should be greater than 4.8 bar (70 psi) to ensure that there is adequate pressure in the system for the ILPCV to be fully tested. **Step 5** - Adjust the test rig gate valve (V.2) to the point at which the flow rate starts to reduce. **Step 6 Test ILPCV for pressure control** - Slowly, over about 30 seconds, close the test rig gate valve (V.2) and record the highest pressure observed on the test rig reference gauge (P.3) during closure from maximum flow to zero flow. - The ILPCV should control pressure smoothly over the closure. Any unusual pressure fluctuation shall be investigated. - The recorded pressure should not exceed 3.8 bar (55 psi) during closure and 4.2 bar (60psi) at shut down. **Step 7** - The pressures indicated on the venturi gauge should be within 0.35 bar (5 psi) of the recorded pressures on the test rig gauge in the range of 2.4 to 3.8 bar (35 to 55 psi) (This is for information only). - If venturi is not fitted go to step (8) **Step 8** - When flow stops, close the test rig ball valve (V.1) and observe final pressure on test rig gauge (P.3) and record the result which should be the same as (P.V). **Step 9 Testing for ILPCV valve slippage** - After waiting for a further 30 seconds, record the test rig gauge (P.3) again. - An increase in pressure at no flow conditions is known as pressure creep and is an indication that the ILPCV seals may be faulty. The maximum allowable pressure creep is 0.35 bar (5 psi). - If the results are outside the specified limits at any test stage, the test should be repeated. If the repeat tests confirm the original results they should be discussed with the supervisor and, appropriate adjustments made, and retests performed. **Step 10** - Shutdown operation and relieve any locked in pressure by opening test rig ball valve. **Step 11** - Remove block out devices from the system under test and repeat steps (2)-(10) for any remaining ILPCV and/ or each venturi/hose configuration. **Step 12** - Complete the documentation - If any ILPCV exceeds the specified limits adjust/overhaul and retest until within limits. - Record any changes and adjustments that were made to the ILPCV and controls. - The In-line pressure control valves without pressure loss compensation (direct sensed) an alternative test protocol can be used for existing non-compensated systems to permit pressure at the pump outlet or entry to the delivery hoses to be limited to a present maximum of 5.5 bar (80psi). - While this system is simple to test and adjust, it is not flow-rate sensitive. Maximum flow performance may be limited due to pressure losses downstream of the control point. - On many applications, the control point is remote from the valve, connection being made via the fuel sense line. - The ILPCV should control pressure smoothly during test rig valve closure. Any unusual pressure fluctuation shall be investigated. - For a non-compensated ILPCV system, the recorded pressures indicated on the fuel sense gauge should not exceed 3.8 bar (55 psi) over the full flow range and shall not exceed 5.5 bar (80 psi) at shutdown. 3. **CHECK VENTURI (COMMISSIONING & TROUBLE SHOOTING ONLY)** ========================================================= 5. **VENTURI SET-UP AND VALIDATION CHECKS** ---------------------------------------- - A venturi compensated system smoothly controls the in-line pressure control valve (ILPCV) or pit coupler. - There are two types of venturis: - Non-adjustable venturis - Adjustable venturis - Venturi do not generally require routine adjustment and hence this test segment does not form part of the quarterly check. - Venturi tubes are not subject to significant wear rates and most problems are due to: - blocked lines/ sense line valves, loose component parts - changes in downstream equipment such as hose length or diameter changes - change of nozzle or nozzle screen mesh size - Adjustment may therefore be required when downstream equipment is changed. - There are three situations where venturi checks shall be conducted: 1. Fuelling unit commissioning 2. Change of equipment downstream of venturi sense point (e.g., different hose length/ diameter, different HEPCV, different nozzle screen mesh size, etc.) 3. Failure to achieve the ILPCV/ pit coupler pressure control limit values - The venturi indicates, via a venturi pressure gauge on fuelling equipment panel, the pressure at the aircraft adaptor. - The fuelling equipment venturi pressure gauge shall be checked against a calibrated gauge before the start of the test. 6. **CHECK VENTURI (COMMISSIONING & TROUBLESHOOTING ONLY) PROCEDURES** ------------------------------------------------------------------- **Step 1** - Air reference pressure should be set to normal position. **Step 2** - Install block out devices on all HEPCV nozzles. **Step 3** - Select a venturi, open all associated nozzles downstream and open relevant test rig valves ensuring any other nozzles and test rig valves are closed. **Step 4** - Establish full flow with deadman. **Step 5** - Slowly close test rig ball valve to achieve the target test rig gauge pressure (anywhere in the range 2.4 to 3.8 bar (35-55psi). Record the actual test rig pressure gauge reading and record corresponding venturi gauge pressure reading on fuelling equipment panel. **Step 6** - Fully close the test rig ball valve and record the test rig pressure gauge reading and the corresponding venturi gauge pressure reading on the fuelling equipment panel. **Step 7** - Calculate the differences and record the results. - If the pressure on the panel gauge varies by more than +/- 0.35 bar (+/- 5 psi) of the pressure, as measured by the test rig pressure gauge, then the venturi is not set up correctly and will require adjustment, overhaul or replacement. **Step 8** - Shutdown operation and relieve any locked in pressure by opening test rig ball valve. **Step 9** - Repeat steps (2)-(8) for each remaining venturi and associated nozzles. - Reset air reference pressure back to normal setting. **Step 10** - Complete the documentation. **DEADMAN CONTROL** =================== - This test is intended to check the controlled rapid shut-down in the event of an emergency and the controlled opening of the system for fuelling. - Deadman systems are fitted to facilitate the shutdown of fuel flow through the vehicle in an emergency. Valves must act quickly to minimize the spill potential however not so quickly to induce surges in the system. - Similarly, for fueller loading facilities, the deadman control shall be performance tested at least monthly. - Annually, check to confirm the intermittent feature of the deadman initiates shutdown of the flow is no more than 2 minutes. **Step 1** - Circulate the fuel at the maximum flow rate. - If the check is carried out during a refuelling, select an aircraft that will accept a high flow rate. Observe bonding procedures. **Step 2 Deadman Opening Time** - Operate the deadman handle and measure the time from when flow first starts until it reaches maximum and record. - The valve opening time should be: - min. 5 seconds for vehicles with flow rates \>2000 LPM - min. 3 seconds for vehicles with flow rates \ 6-inch diameter, gauge at lower level than nozzle; vent port restricted.   ILPCV Restriction in fuel sense line (e.g., closed isolation valve). For venturi systems - sticking \'leaky\' non-return or pilot operated venturi selection valve; excessive venturi compensation. **Result** **Problem Solving Chart -- Interpretation / Possible Cause** Control pressure and flow rates much lower than normal/permitted maximum General Inlet pressure too low; control reference (spring or air pressure) too low. ILPCV Restriction/leakage of air supply; fuel sense pressure inside valve higher than indicated due to internal leakage (displaced seal/broken diaphragm). For venturi systems - isolation of non-active venturi not effective; insufficient compensation. Control pressure and creep at zero flow exceeds set limits General As for during flow + leaking seals; scored seal surface on piston; porous casting, allowing leak past seals.   HEPCV / ILPCV Closure of second rig valve compresses product in enclosed volume.   ILPCV Shock alleviator, if fitted, relieves high pressure into system; inlet pressure higher than design limit of the valve (piston held off its seat). -------------------------------------------------------------------------- -------------------------------------------------------------------------------------------------------------------------------------------------------- ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ +-----------------------------------+-----------------------------------+ | **Result** | **Problem Solving Chart -- | | | Interpretation / Possible Cause** | +-----------------------------------+-----------------------------------+ | Locked in pressure rises and | Test rig valves leaking. | | falls in a | | | | | | rhythmic manner | | +-----------------------------------+-----------------------------------+ | Flow instability - Rapid rise and | Air in fuel sense line, valve | | fall | chamber or filter vessel; | | | SPCV/HEPCV control settings too | | | close together; vacuum in inlet | | | hose (before opening deadman | | | inlet coupler); deadman opens too | | | quickly. | +-----------------------------------+-----------------------------------+ | Deadman opens too quickly, closes | Vacuum in inlet hose; air | | too slowly and overshoot too | pressure too high; fuel | | high. Continued low flow after | restricting orifice in valve too | | \'closure\'. | large or stuck open. | +-----------------------------------+-----------------------------------+ |   | Air restricting (exhaust) orifice | | | too small; air pressure too high; | | | restriction in fuel sense line; | | | excessive delay between deadman | | | release and air exhaust; | | | excessive flow rate \> normal | | | maximum (use rig valve to reduce | | | flow rate - max. 1.4 bar (20 | | | lb/in2) on P.3) | +-----------------------------------+-----------------------------------+ |   | Damaged seal or piston; product | | | level in receiving tank lower | | | than vehicle (fuel continues to | | | flow by gravity, hoses may | | | flatten, air may enter filter | | | vessel); inlet pressure higher | | | than design limit for the valve. | +-----------------------------------+-----------------------------------+ ---------------------------------------------------------------------------------------------------------------------------------------------------------- -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- **Result** **Problem Solving Chart -- Interpretation / Possible Cause** Deadman opening /closing time is outside limits. Opening and closing time is controlled by pilots that have adjustable orifices. Adjusting these will allow fuel to flow in an out of the ILPCV at differing rates that will change the valve opening and closing times. Adjusting the deadman characteristics may change the performance as a pressure control valve and sometimes a compromise is necessary Deadman volume overshoot is too high. The ILPCV will not start to close until the control air pressure has vented from system. To reduce the overshoot volume, increase the rate at which air bleeds when the deadman handle is released. The upstream fuel pressure may also have an impact. ILPCV does not control hose end pressure correctly as measured at test rig gauge. Test rig and venture pressures do not agree when valve is controlling. Adjust the air control pressure as necessary. The venture is normally set when refuelling equipment is first commissioned. The Venturi should only need adjustment if hose lengths / diameters have been changed or components downstream of the Venturi have been modified. ILPCV does not control surge pressure to less than 120 psi.  Ensure that the "effective" closing speed of the test rig valve is not too fast. The 2 seconds should be measured from the time the ILPCV begins to control, i.e. about 35 psi Rig pressure. ---------------------------------------------------------------------------------------------------------------------------------------------------------- --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------