1 Operation & Maintenance Manual Bubble Level Transmitter Power Hydraulic Engineers Operation & Maintenance Manual Bubble Level Transmitter Major components: 1. Air Filter and Regulator -12 bar,14micron Filteration 2. Rotamter 0-20 lpm 3. Pressure Gauge 0-500mb 4. DP Type Smart Transmitter 5. Ball Valve ½ ” BSP 6. Needle Valve ¼” BSP 7. Control Panel 600mmx600mmx250mm
2 Operation & Maintenance Manual Bubble Level Transmitter Description and control of the components Air Filter and Regulator Part No. MS6-LFR-1/2-D7-E-R-M-AS. Technical Specifications : Connection: G 1/2 Filtration: 40 μm Drain: Manual rotating drain Bowl: Polycarbonate with plastic bowl guard Maximum condensate volume: 38 ml Operating pressure: 0.8–20 bar Pressure regulation range: 0.5–12 bar Nominal flow: approximately 4,500 L/min Medium: compressed air / inert gas Temperature: approximately −10 to +60 °C Regulator characteristic: constant outlet pressure with secondary venting Pressure hysteresis: maximum approximately 0.25 bar. Rotamter 0-20 lpm Type: Panel mount Acrylic Rotameter with control valve at bottom Make: From URL japsin.co.in - Japsin Instrumentation Scale: LPM AIR - Liters Per Minute for Air Range: 0 to 20 LPM Tube: Clear Acrylic body with SS float inside Connection: Threaded top + bottom Bottom has control knob for flow adjustment Use: Measuring and controlling air flow How it works: The float rises to the flow rate Read at the center of the float. Right now it's at 0 LPM Pressure Gauge 0-500mb Brand:"Ji" Japsin Instrumentation Product Type:Capsule Pressure Gauge Dial Size:4" (100 mm) Pressure Range:0 to 5000 mmWC Secondary Scale:0 to 500 mBar Mounting Type: Direct Mounting Entry Type: Bottom Entry Connection Size:3/8" BSP (M) Case Material: Stainless Steel Wetted Parts Material:Stainless Steel Pointer Type: Micro Adjustable Pointer Measuring Element: Capsule Element
3 Operation & Maintenance Manual Bubble Level Transmitter DP Type Smart Transmitter Make: Instrument &Systems Type: DP Transmitter - 2 wire, 4-20mA + HART Supply Volt : 24V DC (2 wire) Output : 4-20 mA (HART) Display: Digital LCD on top with blue protective cover Medium: Air / Nitrogen Range: 0to0.6bar Accuracy : ±0.075%of calibrated span Diaphragm: SS316L Ball Valve ½ ” BSP Type: Ball valve. Lever handle = on/off Body: SS316, square block body, panel mount with bracket Connections: Double ferrule compression fitting on top and bottom Handle: Flat SS lever. Parallel to pipe = OPEN, Perpendicular = CLOSED Needle Valve ¼” BSP Type: 2-way, Straight pattern Needle Valve Body: SS316 Handle: T-bar / lever handle for fine throttling Connections: Double ferrule compression fitting 1/4" x 12mm OD tube Use: Isolating pressure gauges, transmitters, fine flow control and tight shut-off
4 Operation & Maintenance Manual Bubble Level Transmitter Standard Operating Procedure Pre-Start Checks Visual Check: Ensure Ball valves (5.1 ,5.2 & 5.3 ), Needle valve (6.1 & 6.2 ) should be in CLOSED position. Air Supply to panel : Confirm Instrument Air from Compressor is clean, dry, oil-free and at 0.4 bar to 0.5 bar. Connect T1 to the compressor through flexible pneumatic tubing or suitable SS Tubing’s. Dip Tube: Confirm dip tube is installed in vessel to required depth. Tube end should be 50-100mm above vessel bottom. DP Transmitter: Confirm DP transmitter is mounted and the pressure line is connected as shown in the lay out. Confirm the Transmitter is calibrated for 0-100% level of fluid level. Drain Pot: Ensure drain pot’s vent line is connected to T3 through flexible pneumatic tubing or suitable SS Tubing’s. Air Supply to drain Pot: The dip tube inlet port has to be connected to T2 of the panel through flexible pneumatic tubing or suitable SS Tubing’s. 5.1 5.2 5.3 6.1 6.2 T 1 T2 T3
5 Operation & Maintenance Manual Bubble Level Transmitter Panel Start-Up Open Air In: Slowly open the ball valves (5.1 & 5.3) and the needle valve 6.2. Set FRL: Adjust Air Filter Regulator (1) to set pressure = 1.5 x Max expected level head in bar considering the maximum fluid level in the drain pot and its specific gravity. Flow regulation: Adjust the Rotameter (4) to control the air flow to around 6-10 lpm just to create slow air bubble formation at the tip of the dip tube inside the drain pot. The goal is Just enough to maintain bubbles, not waste air. Check Pressure Gauge (3): Open the needle valve 6.2 – the Gauge will show the back pressure which is the liquid head, note the reading. Verify DP Transmitter: Check DP transmitter LCD reading. It should match actual vessel level. Normal Operation Monitor: Keep Rotameter flow constant. If flow drops, check filter clogging. DP Reading: DP transmitter converts back pressure to 4-20mA. 0% = 4mA, 100% = 20mA. Drain Pot: Condensate will collect and vent out. Drain periodically if needed. Shut Down Procedure Close the ball Valve (5.3) first to stop purge air. Close Ball Valves (5.1) for AIR IN Vent: Leave "AIR TO DRAIN POT" open to depressurize. Important Notes / Safety Do NOT over-pressurize: FRL pressure should always be > max liquid head, but < tube burst pressure. No Bubbles = Wrong Reading: If Rotameter = 0, DP will read wrong. Check for dip tube choking. Too much flow: Wastes air and gives unstable reading. Keep bubbles slow and steady. Calibration: Since DP is already calibrated, 0% = empty vessel, 100% = max level. Do not change FRL pressure after calibration. Troubleshooting DP reads 0% but tank has liquid : Dip tube is choked or there is no air flow. Check the Rotameter if needed blow through the dip tube. Fot this close the ball valve 5.1&5.3 and both the needle valves 6.1 and 6.2 and let air to pass through the dip tube if needed the pressure may be increase directly prom the compressor control valve to clear the dip tube choking. DP reads 100% always : The ball valve 5.3 is closed air is not coming to dip tube inlet. Open this ball valve and then check the bubble formation takes place slowly and smoothly. Unstable reading : Too much air flow, Foaming inside the drain pot , reduce LPM on Rotameter and ensure bubble formation takes place slowly and smoothly.