- Purpose
1.1. The purpose of this document is to establish procedures for the installation, protection, and commissioning of turboexpanders.
1.2. This document also outlines, in a guideline form, the responsibilities for carrying out those procedures.
- Scope
2.1. The equipment is an CryoMachinery skidded ETAPC-X with lube oil and seal gas systems.
2.2. The installation and erection includes unloading, setting, leveling, anchoring, and grouting the skid.
2.3. External process, cooling water, instrument air/nitrogen piping, supports, and hangers will be installed in accordance with the contract drawings.
2.4. Electrical connections must be made to the lube oil pump motor(s), lube oil heater, and electric actuator (if applicable). In addition, there are electrical connections to be made to the instrumentation on the skid. All connections except for pump motor(s), heater, and electric actuator (if applicable) are taken to terminal strips in junction boxes on the skid.
2.5. All electrical wiring and connections will be done by the Electrical Contractor. All instrumentation installation and calibration will be done by the Instrumentation Contractor.
2.6. Commissioning and start-up includes; field piping inspection, lube oil system inspection and flush, seal gas system inspection, instrumentation calibration, operational function checks, compander readiness inspection.
- Responsibilities
3.1. The Construction Field Superintendent has overall responsibility for the construction contract. He should be responsible for the implementation of these procedures and for the proper installation and start-up of the supplied equipment. He should coordinate the Contractor’s efforts and ultimately be responsible for accepting the compander skid from the Contractor.
3.2. The Construction Field Superintendent may delegate his authority in technical areas to the following individuals:
3.2.1. Machinery Engineer and/or Mechanical Technician
3.2.2. Instrument Technician
3.3. The Machinery Engineer should assist in the technical supervision required for the proper installation, erection and assembly of the CryoMachinery supplied equipment.
3.4. The Machinery Engineer should also have the following responsibilities:
3.4.1. To assist in any liaison between the site and the CryoMachinery office.
3.4.2. To take an initial inventory of the supplied equipment, and notify the Construction Superintendent of any shortages or part discrepancies throughout the job.
3.5. The Instrument Technician should report to the Construction Superintendent and assist in technical areas concerning the installation, inspection and calibration of instrumentation for the vendor supplied equipment.
3.6. The Construction Superintendent is responsible for ensuring that each of the tasks in this procedure have been properly completed.
3.7. The following drawings should be available for use during the installation, commissioning and startup of the equipment covered in this procedure:
- General Arrangement (Skid)
- Outline Turbo-Exp ETAPC-X
- Product Definition Specification
- Assembly Accessory System
- Instrument Termination and Wiring Diagram
- Plant P&ID
- Installation
4.1. Equipment Unloading and Storage
4.1.1. The Contractor will be responsible for the proper rigging and lifting of the equipment. The construction superintendent shall insure that the proper size fork truck or crane, cables, eyebolts, slings, etc. are available for the lift. He shall also inspect and APPROVE the rigging prior to any lift.
4.1.2. It is intended that the compander skid be lifted directly from the shipping container onto its foundation. The skid should be unloaded and stored until all possible CryoMachinery equipment field piping is fabricated.
4.1.2.1. The compander skid (if necessary) should be stored on a level plot. Preferable storage is indoors in a dry atmosphere. If indoor storage is not available, ensure that the packaging and crating are intact and try to store in a sheltered and dry area. If necessary, elevate equipment on cribbing to prevent equipment from resting in ground water.
4.1.2.2. The best preservation effort for the equipment is to ensure that the preservation techniques employed by CryoMachinery have not been compromised. Ensure that all connection ports remain plugged and the sealed, dry atmosphere plastic enclosure around the compander remains sealed. If the plastic enclosure has been opened, reseal to an airtight state.
4.2. Setting, Leveling, and Anchoring
4.2.1. Remove sealed plastic from around compander. Leave all process, oil and seal gas blanking flanges and plugs in place to avoid contamination of the internals of the compander.
4.2.2. Prior to the setting of the compander skid on the foundation, be certain that the grout area of the foundation has been roughened by chipping to the aggregate.
4.2.3. Lifting cables should be rigged so as to brace against the base frame and not against piping or panels. Wood chucks and appropriate spreader beams should be used as necessary.
4.2.4. Clean and degrease the bottom of the framework over the grout area. The framework should be free of rust, flaking paint, moisture and oil.
4.2.5. Place the skid on its foundation using the compander process connections to rough align placement of the skid. Any misalignment of process connections after skid placement will have to be made up in piping spools. The compander skid framework should be leveled to a .003 slope maximum. Allow for a nominal grout thickness of one inch (25 mm). Support the framework uniformly at least every three feet (.92 m) using wedges. Anchor bolt locations shall be laid out and anchor bolts (supplied by CryoMachinery) shall be installed in accordance with the manufacturer’s instructions.
4.2.6. After insuring that the base has been leveled and the anchor bolts are snug, the compander skid should be grouted using non-shrink grade grout in accordance with the appropriate grouting schedule. Pour grout in accordance with proper specification.
4.2.7. Allow grout to cure fully before removing wedges and tightening the anchor bolts. Patch wedge voids with grout after removal. Seal grout as required in the grout schedule.
4.3. External Piping Connections
4.3.1. The Contractor is responsible for the installation/erection of all loose piping and components (i.e., lube oil reservoir demister and associated piping) shipped with the accessory system. The most important of these loose piping items are the expander discharge diffusers. They must be installed in the outlet piping of the expander as shown on the CryoMachinery Outline TurboExp drawing.
NOTE: The Contractor should ensure that flex hoses or expansion joints, where used, are of the proper construction and pressure rating, and are installed such that they have no kinks, tight bends, damage, or rubbing against supports.
4.3.2. The Contractor is responsible for making the external piping ties to the inlet and discharge process connections to the turboexpanders . Proper protection shall be observed by covering the process connections to avoid getting weld slag, moisture and dirt into the machine. Use a 20 gage (0.9 mm [0.036 inch]) minimum sheet metal cover taped to these openings to seal the process connections. After the turboexpander has been used for piping fit- up, it should be sealed and secured properly until process, defrost and vent, and seal gas piping blowdown has been completed. Secure all connections including expander and compressor process connections.
4.3.3. The Contractor is responsible for piping the cooling water lines to the oil cooler.
4.3.4. The Contractor is responsible for piping any seal gas/instrument supply lines to the compander skid. The Contractor is responsible for piping any seal gas return lines away from the compander skid. Piping should not be connected to the accessory system until the lines going to the skid have been blown down and the cleanliness checked.
4.3.5. If applicable, the Contractor is responsible for mounting the rundown tank and check valve above the lube oil skid and piping the rundown tank supply and return lines. Piping should not be connected to the accessory system until the lines going to the skid have been blown down and the cleanliness checked. The Contractor should insure that the check valve in the return line is installed in the proper orientation as shown on the plant P&ID and that the return line is free draining.
4.4. Electrical and Instrumentation Installation
4.4.1. The Contractor is responsible for installing Miscellaneous instrumentation that may be shipped loose with the CryoMachinery package for reasons of protection.
4.4.2. Make the following electrical connections: Lube oil pump motor(s), lube oil heater, electric actuator (if applicable), main terminal box power supply, and other connections as indicated on the Instrument Termination and Wiring Diagram.
- Commissioning
5.1. Instrumentation and Electrical Calibration
5.1.1. Check that all pressure gauges and transmitters are calibrated and operational. (See CryoMachinery Product Definition Instrument Summary for listing of pressure devices.)
5.1.2. Check that all temperature gauges, elements and transmitters are calibrated and operational. (See CryoMachinery Product Definition Instrument Summary for a listing of temperature devices.)
5.1.3. Check vibration probe(s). Check DCS for proper connection and operation. Set the alarm and shutdown settings per the set points listed in the CryoMachinery Product Definition Instrument Summary.
5.1.4. Check/set gap of the vibration probe(s) per CryoMachinery Outline Turbo-Exp drawing notes.
5.1.5. Loop check the vibration system.
5.1.6. Check the speed indication, alarm, and shutdown system.
5.1.7. Check the tachometer for proper connection. The tachometer should be wired per CryoMachinery Instrument and Wiring Termination Diagram.
5.1.8. Check/set speed probe gap per the CryoMachinery Outline Turbo-Exp drawing notes.
5.2. Process Piping Blowdown
5.2.1. Before piping blowdown, remove inlet screens from piping upstream of compander. Apply the following guidelines to prevent blowing through the compander during process air line blowdown. Seal the process connections on the compander with a minimum of 20 ga. (0.036 inch [9 mm] ) thick sheet steel or 0.5 inch (12.7 mm) thick plywood blinds gasketed between the compander and the blinds. It is imperative that all connections remain sealed to prevent dirt from entering.
It is acceptable to tape the sealing gaskets and covers to the inlet and discharge flanges. Whether or not tape is used to hold the gasket and cover in place, cover the edge between the cover and the flange with tape.
5.2.2. The sealing of the process flanges of the turboexpander should be inspected and approved by the Construction Superintendent or Machinery Engineer.
5.2.3. During the blowdown, the Contractor should supply appropriate fittings/shielding to direct the blowdown outside of the box.
5.2.4. Blowdown and piping connection to compander should be done in the presence of the Machinery Engineer.
5.2.5. The Machinery Engineer is to inspect and approve the cleanliness of any loose piping spools which were removed during the piping blowdown prior to their installation.
5.2.6. The Machinery Engineer should inspect the inlet screens for the compander. The screens should be checked for proper mesh size, materials, structural integrity and cleanliness.
5.2.7. The Machinery Engineer should witness the installation of the inlet screens to insure that the screens are installed in the proper orientation and to see that cleanliness is maintained.
5.2.8. The Machinery Engineer should make certain the sheet metal diffusers are properly installed and gasketed in the expander and/or compressor discharge flanges. See CryoMachinery Outline Turbo Exp drawing for details.
5.2.9. Prior to installation of the compressor inlet spool(s), the Machinery Engineer should check to ensure that the rotor turns freely. Manually rotate the turbine rotor. The rotor should be capable of being turned readily by fingertip pressure at the eye of the compressor wheel.
NOTE: The ETAPC-X is available with fixed geometry taper land bearing or tilt pad bearings. If the bearings are taper land, there will be a difference in feel depending on the direction of rotation. The rotor will spin most freely in the proper operating spin direction. In the opposite direction of rotation, the taper land journal bearings cause a characteristically greater resistance to spin. If the bearings have tilting pads for journals and thrust faces, there will be the same resistance rotating in either direction.
5.2.10.The process and defrost gas piping should now be reconnected. The Machinery Engineer should check all inlet and discharge flange loads on the turboexpander to ensure no cold-pull is incorporated into the final installation. That is, when the mating flange of the piping is set, the flange bolts should be able to drop through both sets of flange holes (piping and turboexpander) without any force fitting. Never use crowbars, chain hoists, pipe wrenches, etc. to assemble process piping to the turboexpanders.
NOTE: Exercise extreme caution when removing the protective covers from the turboexpanders so that no dirt or rock wool enters the pipe or the machinery.
5.3. Seal Gas and Instrument Air Piping Blowdown
5.3.1. Instrument and seal gas piping to the compander skid should be blown down with the seal gas filter cartridges removed. Blow down the pipe in sections. Remove all regulators and solenoid valves from the piping and open all vent or bleed valves. Do not connect the piping at the compander skid. Blow out all sections of the pipe in the presence of the Machinery Engineer. Upon Machinery Engineer approval, close all vents and bleeds, replace removed components and remove all seal gas pipe covers at the compander. Connect seal gas piping to the compander skid. Seal gas piping on the compander skid has been cleaned and does not require blowdown unless it has been contaminated during shipping storage, or field piping installation.
All threaded seal gas supply connections on the compander should be sealed with pipe dope, not Teflon tape. Be careful to ensure a minimum amount of pipe dope is used and the first few threads entering the machine do not have any sealant. This is to ensure that seal passages will not become plugged.
5.4. Lube Oil System Setup/Installation
5.4.1. Ensure coalescing filter housing (demister) is installed on reservoir. Drain tube should run from filter housing to the proper connection on the top of the reservoir. Ensure coalescing filter elements are installed properly and not damaged.
5.4.2. Fill tank to proper operating level with correct grade oil (See Product Definition Specification Lube Oil System section for the oil grade). NOTE: If accessory system is equipped with a reservoir level switch, check functioning of low level alarm and permissive start of the reservoir heater as reservoir is filled. Record oil type used during filling if the oil is to remain the operating oil after the flush is complete or if there is no flush.
5.5. Lube Oil System Flush
5.5.1. The lube oil flush should be performed under the supervision of the Machinery Engineer.
5.5.2. Connect a jumper line from the lube oil supply line to the lube oil drain line. Install a blind on the turbine drain to prevent oil migrating into the unit if the drain piping is to be left connected to the compander. It is permissible to leave a small section of the drain line near the compander out of the flushing circuit. Inside diameter of the jumper line is to be no less than that of the normal oil supply piping.
5.5.3. Install 100-mesh wire screen in the oil supply line where it connects to the jumper line. Under the supervision of the Machinery engineer, remove oil supply piping not in the flush circuit. After the lube oil flushing is complete the remaining piping can be flushed clean with solvent, approved for cleanliness and re-installed to the turboexpander.
5.5.4. Ensure oil filter element(s) are installed in filter housing(s) and internals of oil filter are clean.
5.5.5. Heat oil to a temperature of 130o F (55o C).
5.5.6. Jumper turbine seal gas switches as required or establish seal gas to the compander.
5.5.7. Bump oil pump(s), check for proper rotation.
5.5.8. Start oil pump and check to see that oil is circulating satisfactorily. Run both pumps at the same time, if dual pumps are supplied. Listen for any unusual sounds from the pump(s).
5.5.9. With one pump operating, be sure that the lube oil supply PSV and PCV are set per the CryoMachinery Product Definition Instrument Summary and check for any leaks in the lube oil piping and components.
5.5.10. Crack open any air vents on top of oil filter and oil cooler. Regularly check oil temperature and differential pressure across filter. A complete set of spare filter elements should have been delivered to site. If the oil filter system has dual housings, alternate the flow through both housings during the flush.
5.5.11. Make sure that the cooling water is not flowing through the cooler. This will allow the oil to flow through the cooler.
5.5.12.Flush the rundown tank or accumulator (if applicable) several times during the oil flush. To do this, stop the pump. The rundown tank or accumulator should provide positive oil pressure for several seconds as the pressure decays.
5.5.13.The oil flush should be done with both pumps operating, if dual pumps were provided. Circulate the oil for 8-12 hours while occasionally rapping on the piping throughout the system to loosen any internal scale, rust or contamination. Occasionally remove, inspect, and clean the 100-mesh screen. Continue the flush until the Machinery Engineer is satisfied that the 100-mesh screen indicates that the oil system is clean of all foreign matter.
Note: The 100 mesh screen is to be supplied and installed by the Contractor.
5.5.14. During lube oil circulation, start coolant flowing through the lube oil cooler. Use the supplied coolant vent and drain valves to flush out any contaminants that may be present. Verify correct operation of the oil temperature control valve. The valve should maintain a constant oil discharge temperature as listed on the CryoMachinery Product Definition Instrument Summary. Shut off the coolant for the remainder of the oil flush.
5.5.15.When lube oil flush is complete, rack out lube oil pump motor(s). Drain oil and replace with new oil if flushing oil was used or if it is deemed necessary by Machinery Engineer. Record the oil type used.
5.5.16. Inspect oil filter. Drain, clean and install new filter element(s).
5.5.17. Reset the lube oil reservoir heater to the setting listed in the CryoMachinery Product Definition Instrument Summary.
5.5.18. Prepare the turboexpander for operation after any flushes or initial commissioning. Remove any seal gas bypasses. Reconnect all seal gas tubing. Clean as necessary. Ensure that the oil supply and drain lines are installed and any blanks or screens, if used during a flush, are removed.
5.6. Adjustable Inlet Nozzles
5.6.1. Stroke the inlet nozzles to ensure nozzles are free to move and are calibrated correctly. Note that nozzle stops are pre-set and should not be altered.
5.6.2. Check the functional operation of the actuator, any I/P converters, as well as local and remote hand controls and nozzle position indicators.
5.7. Alarm and Shutdown Logic Checkout
5.7.1. Inspect compander to ensure all oil and seal gas lines are properly connected.
5.7.2. Establish seal gas to the compander. Set the startup seal gas regulators to their appropriate settings per the CryoMachinery Product Definition Instrument Summary. If possible, also feed the compander using the operating seal gas regulators so that they can be set. Ensure that seal gas is being fed to the compander.
5.7.3. Check to ensure that the lube oil in the reservoir is at least 60o F (20o C). Energize the lube oil pump(s) and start the lube oil system to circulate oil to the compander.
5.7.4. Make sure that the inlet and discharge manual block valves for the compander are closed. Open the turbine trip valve(s). If the turboexpander has a compressor recycle valve, close the valve.
5.7.5. For skids with dual oil pumps, start one pump and slowly decrease the lube oil supply pressure by adjusting the oil pressure control valve. Check that the low oil pressure alarm alerts and the other oil pump starts at the appropriate pressure shown on the CryoMachinery Product Definition Instrument Summary. Stop the first pump, and repeat with the second pump. Rack out one pump for the next operation.
5.7.6. Slowly decrease the lube oil supply pressure by adjusting the oil pressure control valve. Check that the low oil pressure alarm alerts at the appropriate pressure shown on the CryoMachinery Product Definition Instrument Summary. Continue to decrease the lube oil pressure until the low lube oil pressure shutdown set point, as shown on the CryoMachinery Instrument Summary, is reached. At this point the shutdown notification should occur and the turbine inlet trip valve(s) should close fully within one second.
Caution: The inlet trip valve(s) must operate from fully open to fully closed in 1-2 seconds max. before operating the compander.
5.7.7. Reset the oil pressure control valve to its proper setting. Reset/reopen the turbine inlet trip valve(s).
If the accessory system is equipped with dual pumps, have both pumps running for the following section.
5.7.8. Caution: The following procedure is to be performed carefully. Slow gentle adjustments must be made to the seal gas regulators. Do Not simply shut off the seal gas. Doing so would impose a totally artificial condition on the systems which could result in lube oil migration along the shaft contaminating the process lines and the turbine nozzle mechanism.
Slowly adjust the appropriate seal gas regulator(s) to reduce the seal gas pressure to the turbine. Check to see that the low seal gas pressure alarm sounds at the appropriate pressure. Continue to slowly reduce the pressure until the low seal gas shutdown set point is reached, at this point, the lube oil pump(s) should stop, the inlet trip valve should close and the rundown tank or accumulator should supply approximately ten seconds of flow of oil to the turbine. Be sure all of these actions occur properly before continuing.
5.7.9. With the seal gas pressure 2-5 psi below the low shutdown value (but not off!), try to restart oil pump(s) at this point. The oil pump(s) should not restart. Readjust seal gas regulator(s) to correct set point per the CryoMachinery Product Definition Instrument Summary.
5.7.10.To function check the rundown tank (if applicable), start the pump and run until oil is detected by the flow indicator in the rundown tank return line. While watching the lube oil supply pressure, shut off the pump. There should be a sudden drop of pressure, and then there should be a positive pressure of at least 0.07-0.14 barg (1-2 psig) for a minimum of 10 seconds. If this does not occur, check that the check valve in the return line is installed and functioning correctly, that the return line is free draining, and that the rundown tank is mounted at the correct height (approximately 12 m above compander’s centerline).
WARNING: Proper functioning of the rundown tank is critical to machine reliability during certain shutdowns. The rundown tank test must be done correctly to ensure that the rundown tank is functioning properly.
5.7.11. Check speed alarm and shutdown settings listed on the Product Definition Instrument Summary by inputting a signal to tachometers as follows:
5.7.11.1. Check the alarm and shutdown set points of the tachometer internal relay(s). Verify the set points by connecting a signal generator to the input signal terminals of the tachometer. The proper frequency signal is found using the following formula:
Frequency(Hz) = RPM /10
For example, the frequency corresponding to 30,000 rpm is 30,000 rpm/10 = 3,000 Hz
5.7.11.2. Slowly increase the frequency to simulate shutdown speed. Check to see that the high- speed alarm and shutdown occur at the correct speeds. When shutdown notification occurs, the turboexpander inlet trip valve should close, and the compressor recycle valve (if applicable) should open.
5.7.11.3. Repeat 5.7.11.2, except this time quickly ramp up to verify that there is no delay on the high speed shutdown. The shutdown notification should immediately occur once passed the frequency corresponding to the shutdown speed.
5.7.11.4. Simulate a speed of 1000 rpm. After a period of about 30 seconds, the low speed alarm should activate.
5.7.12. Check vibration alarm setpoint. Be sure the alarm sounds at the appropriate setpoint.
5.7.13. Check vibration shutdown setpoint. At correct setpoint shutdown notification should occur and turbine inlet trip valve should close fully within one second.
5.7.14. Check that the compressor inlet temperature will alarm and shutdown the turboexpander at high inlet temperature as defined on the Product Definition Instrument Summary.
5.7.15. Check that the turboexpander lube oil supply temperature will alarm at high inlet temperature as defined on the Product Definition Instrument Summary.
5.8. Preservation: The compander skid is suitably preserved for a minimum of six months outdoor storage as long as all covers shipped on the unit are maintained. After a six month period, nitrogen or dry air purges on the seal gas and oil systems are recommended. The purges should be connected to ensure that the reservoir, as well as all piping and components will be protected. Introduce the nitrogen or dry air purge at start-up seal gas inlet on the skid. Be sure the start-up seal gas regulators are set to allow flow through the compander. Allow purge to exit the reservoir through the demister vent or break a connection (such as the oil fill cap), but under no circumstances should this bleed allow dirt or moisture to enter the reservoir. Purge should be done in this manner so purge gas cannot pick-up any oil mist or vapor from residual oil in the reservoir or piping and blow it into the nozzle mechanism or process areas of the compander and seal gas piping.
Important: The appropriate purges (if used) should be disconnected prior to filling the lube oil reservoir with oil or performing any work on the oil or seal gas systems under purge. Adequate warning signs shall be placed on the skid to indicate the equipment is under purge.
Safety note: Discontinue any purges on the turboexpander, the oil reservoir, or the associated piping before opening the reservoir. Open lube oil reservoir and clean out any dirt or loose particles. Close reservoir inspection cover.