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I. Starting a reciprocating compressor: 1. Preparation work: A. The installation personnel check whether all components of the main unit have been installed properly, and ensure that the clearances between all moving parts meet the required standards. B. Notify the electrician to check whether the motor insulation (above 0.4M) and the technical condition of the electrical switches meet the requirements; also notify the instrumentation team to check whether the measuring instruments and control protection devices are in good working condition. C. Clean the area, removing all dust and oil from the surfaces of the equipment and workbenches. D. Inspect or clean the circulating oil system (including the oil tank, crankcase, oil pump, filters, cooler, oil pipes, valves, and oil circuits for moving parts). In particular, the iron shavings and hard debris in the oil circuit system should be thoroughly cleaned out. After thorough cleaning, pour fresh lubricating oil into the tank, start the oil pump, and check its operation as well as for any leaks in the oil circuit (the oil pressure must not be lower than 0.25 MPa). E. Inspect or clean the oil injector to ensure proper operation, unobstructed oil flow, no leakage points, appropriate oil dosage (10 drops per minute), and clean oil quality. F. Open the main cooling water valve, as well as the inlet and outlet valves for the cooling water in the cylinder water jackets, packing, and oil cooler, and check whether the water pressure, quality, and volume meet the requirements. 2. Testing steps: A. Open the cooling water valve and adjust the water flow. B. Start the circulating oil pump, adjust the oil pressure to above 0.25 MPa, and check whether the pressures at all pressure measurement points are equal (including springs, pressure gauges, electrical contacts, and pressure relays). Apply sufficient lubricant to all friction surfaces of the transmission, then stop the pump. C. Manually operate or start the oil injection pump to fill the cylinder with an adequate amount of lubricating oil, then stop the pump. D. Rotate the crankshaft several times to form a layer of lubricating oil film on all the friction surfaces and the cylinder wall surfaces. (When using the cranking mechanism to crank the shaft, first move the handle to the cranking position before starting the cranking motor. Run it for 3–5 minutes; there should be no dead points when cranking in either direction, and the cranking mechanism must be sensitive and reliable.) Then move the turning gear to the startup position and stop the turning gear motor. ) E. Notify the main substation by phone to supply power to the host. F. Start the circulating oil pump, oil injection system, and circulating fan. G. Starting the host 3. Precautions for starting up: 1. Do not turn the machine while it is under pressure. 2. The increase in pressure and dosage must be gradual. 3. Operate the valves slowly, without haste, and pay close attention to changes in current. II. Precautions for normal shutdown: 1. Shutdown is prohibited when there is pressure remaining (the gauge pressure in each section has not been reduced to zero). 2. The circuit valves at all levels should not be opened too quickly or to a maximum extent, in order to prevent backflow of gas and liquid. 3. The main unit must be shut down first, followed by the auxiliary unit. III. Ten Common Faults and Their Solutions Fault 1: Abnormal noises from the crankcase. Causes: (1) Loose crosshead pins or crosshead pin caps ； (2) Wear or looseness of the main shaft bearings, crosshead bearings, and connecting rod bearings ； (3) Low oil pressure ； (4) Low oil temperature ； (5) Incorrect oil type ； (6) Cylinder noise. Exclude: (1) Check whether the crosshead pin and crosshead pin cover are loose; tighten any loose components ； (2) Check the clearances of the main shaft bearings, crosshead bearings, and crosshead shaft bearings to determine if there is wear or looseness; tighten or replace the relevant components ； (3) Check whether the oil pressure is low and for any leaks; increase the oil pressure and repair the leaks ； (4) Check whether the oil temperature is too low; increase the oil temperature under loading conditions, and reduce the flow rate of cooling water to the oil thermostat ； (5) Check whether the oil is correct; replace it if it is incorrect ； (6) Check whether the piston nut is loose and tighten it if necessary. Reason for fault 2: Compressor will not start. (1) Drive unit failure ； (2) Startup disk switch failure ； (3) Fault in the hydraulic start switch ； (4) Control panel failure ； (5) Excessively high pressure in the cylinder ； (6) The starting device is locked. Exclude: (1) Check whether there is a fault with the drive motor, and readjust the power ； (2) Check the circuit ； (3) Check the oil pressure, adjust or replace the switch ； (4) Check the circuit connections and settings of the control panel ； (5) Adjust the pressure inside the cylinder to the normal value ； (6) Check whether the starting device is locked, and release the lock. Cause of fault 3: Crankshaft oil seal leakage: (1) Incorrect installation of the oil seal ； (2) The oil drain hole is blocked. Exclude: (1) Reinstall the oil seal according to the inspection standards ； (2) Clean the oil seal drain hole and remove any blockages. Cause of fault 4: Oil scraper leakage: (1) Wear of the oil scraper ring ； (2) The oil scrapper ring is not installed correctly ； (3) Piston rod wear or scratches ； (4) The ring side clearance is incorrect. Exclude: (1) Replacing the oil scrapper ring ； (2) Check whether the oil scrapper ring is installed correctly, and install it in accordance with the inspection standards ； (3) Repair or replace the piston rod ； (4) Replace piston rings and support rings. Cause of fault 5: low oil pressure. (1) Air entrainment in the oil pump ； (2) The rotating part slaps the oil surface to create foam ； (3) Low oil temperature ； (4) The oil filter is dirty ； (5) Loss of lubricating oil in the engine ； (6) Excessive leakage from main bearings ； (7) The pressure setting of the pressure regulating valve is too low ； (8) Oil pressure gauge failure ； (9) Oil pressure control valve failed ； (10) The oil tank inlet is blocked. Exclude: (1) Repairing or replacing the worn oil pump ； (2) Lower the oil level in the oil tank ； (3) Use a crankcase immersion heater or electric tracing for heating ； (4) Clean the oil filter or replace the filter element ； (5) Check the oil circuit ； (6) Adjust the main bearing clearance ； (7) Reset the pressure of the pressure regulating valve ； (8) Replace the oil pressure gauge ； (9) Adjust, repair, or replace the oil pressure control valve ； (10) Clean the inlet pipe of the oil tank. Cause of abnormal noise in cylinder 6: (1) Loose piston ； (2) Piston impacts the outer end or inner end ； (3) Crosshead lock nut is loose ； (4) Air valve leakage or damage ； (5) Damaged piston rings ； (6) The valve sealing air cushion is damaged. Exclude: (1) Check whether the piston nut is loose; tighten any loose nuts ； (2) Check the clearance at the outer or inner end of the piston, and adjust it to the correct position ； (3) Tighten the crosshead lock nut ； (4) Check whether the air valve has leaks or damage; repair or replace the valve ； (5) Replace damaged piston rings ； (6) Replace the sealing air cushion. Cause of seal overheating in fault 7: (1) Lubrication failure ； (2) The lubricating oil fails to meet the standards or the amount of oil is insufficient ； (3) Insufficient cooling water (especially for water-cooled gaskets) ； (4) The gap is incorrect. Exclusions: (1) Replacing the lubricating oil check valve or lubricating oil pump ； (2) Use qualified lubricating oil and increase the amount of lubricant ； (3) Reduce the cooling water inlet temperature ； (4) Adjust the gap. Cause of seal leakage in faulty disk 8: (1) Wear of the seal ； (2) Lubricating oil is substandard or the oil level is low ； (3) Dirty packing ； (4) Excessive rapid increase in pressure ； (5) The packing is not installed correctly ； (6) Incorrect opening or side gap ； (7) Packing drain plug ； (8) Scratches on piston rod ； (9) The roundness of the piston rod is out of tolerance. Exclude: (1) Replace the gasket ； (2) Replace with qualified lubricant and increase the amount of lubricant ； (3) Clean the packing box and pipelines ； (4) Reduce the pressure increase gradient ； (5) Install the gasket correctly in accordance with the inspection standards ； (6) Check and adjust the clearance ； (7) Check that the packing drain is open to allow drainage at the lowest point ； (8) Repair or replace the piston rod ； (9) Adjust the crosshead shims to the appropriate position to reduce the roundness error of the piston rod. Cause of excessive carbon buildup on valve 9 in case of failure: (1) Excessive lubricating oil in the cylinder ； (2) Cylinder lubricating oil failed inspection ； (3) Carbon carried by oil at the point of import or supply ； (4) Valve leakage or damage, resulting in high temperature ； (5) Excessive pressure gradient in the cylinder, high temperature. Exclude: (1) Reduce fuel supply ； (2) Use qualified lubricating oil ； (3) Install a filtration separator or sewage discharge system ； (4) Repair or replace the valve assembly ； (5) Check the air valves inside the cylinder and clean the water jacket. Cause of fault 10: High exhaust temperature: (1) Leakage in the intake valve ； (2) Exhaust valve or piston ring leakage ； (3) High intake air temperature ； (4) Blocking water in the water tank jacket ； (5) The cylinder lubricating oil is substandard or the flow rate is insufficient. Exclude: (1) Repairing or replacing the faulty intake valve or piston rings ； (2) Repair or replace the intake valve or piston rings ； (3) Clean the air cooler ； (4) Clean the cylinder water jacket ； (5) Use qualified lubricating oil and the correct flow rate.