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Confidential HITACHI OIL-FREE SCREW COMPRESSOR NEXT series Mechanical SERVICE MANUAL Air-Cooled DSP-45AT6N DSP-55AT6N DSP-75AT6N DSP-55VATN DSP-75VATN Water-Cooled DSP-45WT6N DSP-55WT6N DSP-75WT6N DSP-55VWTN DSP-75VWTN “Instructions for the use of this manual” Use this Service Manual in conjunction with Instruction Manual. DSP–017...
1. GENERAL DESCRIPTION 1.1 Appearance Air-Cooled [Front View] Enclosure E n c l o s u r e p a n e l s lower the sound level Air Exhaust Air Exhaust of the air compressor (Air Compressor Package) package. This panel discharges the hot air generated in the air compressor.
1.3 Appearance Water-Cooled [Front View] Enclosure Air Exhaust E n c l o s u r e p a n e l s Air Exhaust (Air Compressor Package) lower the sound level of the air compressor This panel discharges package. the hot air generated in the air compressor.
2. FLOW DIAGRAM 2.1 Flow Diagram Air-Cooled 2.1.1 Fix speed type Compressed Air Flow and Oil Flow Air exhaust Air exhaust Air exhaust Compressed air discharge MOHR Intercooler condensate Air intake for drain main motor Control air for OMR 63SV Air intake for compressed air Oil drain...
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2.1.2 Air-Cooled Compressed Air Flow and Oil Flow Air exhaust Air exhaust Air exhaust Compressed air discharge Intercooler condensate Air intake for drain main motor Control air for OMR 63SV Air intake for compressed air Oil drain Oil drain Aftercooler condensate drain Cooling air flow Compressed air flow Lubricating oil flow...
2.2 Flow Diagram Water-Cooled 2.2.1 Fix speed type Compressed Air Flow and Oil Flow Air exhaust Air exhaust Compressed air discharge MOHR Intercooler condensate Air intake for drain main motor Control air for OMR 63SV Air intake for compressed air Oil drain Oil drain Aftercooler condensate drain...
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2.2.2 Water-Cooled Compressed Air Flow and Oil Flow Air exhaust Air exhaust Air exhaust Compressed air discharge Intercooler condensate Air intake for drain main motor Control air for OMR 63SV Air intake for compressed air Oil drain Oil drain Drain discharge Cooling air flow Compressed air flow Lubricating oil flow...
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Cooling Water Flow Intercooler Aftercooler 2nd-stage airend Oil cooler 1st-stage airend Motorized water isolation Water relief pet cock valve (WIVM) Cooling Cooling water water outlet inlet Cooling water outlet Compressed air flow Cooling water flow...
2.3 Capacity Control System Standard Air-Cooled Water-Cooled 2.3.1 Fix speed type (Load-Unload Operation) The unloading process occurs when the compressed opens and exhausts the internal compressed air to air demand decreases and the discharge pressure rises atmosphere. as high as cut-out pressure. The pressure sensor (PS) The loading process occurs when the compressed air detects the high pressure and energizes the 3-way demand increases and the discharge pressure dropped...
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2.3.2 Fix speed type (AUTO Operation) Air-Cooled Water-Cooled AUTO operation is the Auto start - stop function in When the load ratio is less than 30%, CPU stop the main addition to a standard on-off line, 0% or 100% capacity motor.
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2.3.3 Capacity Control System Air-Cooled Water-Cooled Air intake Purging Air Flow and Action of Blowoff Solenoid Valve Blowoff solenoid Blowoff solenoid Operation phase Air Intake filter 1st-stage blowoff solenoid valve (2) valve (1) valve (2) Starting Fully opened Fully closed Loading Fully closed Fully closed...
3. MAINTENANCE 3.1 Standard Maintenance Schedule Maintenance Schedule A (for 8,000 hours/year or less operation) Follow this schedule (A) if the MAINT.SCHEDULE : A appears on the LCD monitor. ○●… Replace △○… Complete service in house △▲… Clean or check ▲●…...
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Category Part or Item Action Type Remarks 1-year 3-year Check / Clean Fixed / V Clean as required. Orifi ce- Aftercooler condensate ▲ Orifi ce and check valve- Intercooler condensate Check / Clean Fixed / V Clean as required. ▲ Check / Clean Fixed / V Aftercooler/ Intercooler/ Oil cooler...
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Maintenance Schedule B (for 4,000 hours/year or less operation) Follow this schedule (B) if the MAINT.SCHEDULE : B appears on the LCD monitor. ○●… Replace △○… Complete service in house △▲… Clean or check ▲●… Ask your distributor to service Daily Schedule (for 4,000 hours/year or less operation) Part or Item...
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Part or Item Action Category Type Remarks Check / Clean Fixed / V Clean as required. (Air-cooled 125psi (0.86)MPa type) Hi-Precooler ▲ Check / Clean Fixed / V ▲ Demister - Drain separator Check Fixed Replace as required. 3-Way solenoid valve & capacity control system ▲...
3.2 Maintenance Schedule for Oil Mist Remover ① To ensure long and successful operation of the Oil ③ These maintenance inter vals are not considered Mist Remover, follow the standard maintenance warranty. schedule attached below. ④ If an inspected par t is worn, faulty or damaged, ②...
4. HOW TO SERVICE THE AIR COMPRESSOR Before servicing the air compressor, stop it, disconnect the power (turn off the earth leakage (ground) circuit breaker) and verify that the compressor’s internal pressure has dropped to atmospheric pressure. The maintenance intervals shown refer to the standard Maintenance Schedule (A). 4.1 Replacement of Air Intake Filter (Bi-Annually) A pressure sensor is provided on the suction throttle valve to detect the pressure differential across the air...
4.2 Condensate drain port (Intercooler/Aftercooler) (Daily check) Clean the strainer elements (Bi-Annually) & Orifices (Annually) ■ Check the condensate drain Moisture in the intake air, especially in hot and humid environments, is condensed inside the air compressor during compression. Daily inspect intercooler/aftercooler condensate drain to verify that there is a discharge of compressed air (with condensate) when the air compressor is loaded.
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■ Depressurizing the System Before cleaning the drain pipe, intercooler, Aftercooler side aftercooler, control line filter, or replacing the check Ball valve (2) Three-way change valve valve, reduce the internal pressure to 0 (zero) by opening the condensate drain. Stop the air Ⓔ...
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◆ Cleaning of strainer ■ Cleaning of strainer element The strainers for both the intercooler and aftercooler shall be cleaned. ① Discharge the compressed air in the procedure in page 20. ② Loosen the plug of strainer slowly with release the Element internal pressure.
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■ C leaning the strainer element during operation I f the strainer needs to be cleaned while the air Aftercooler side compressor is running, contact the local HITACHI distributor/master dealer or representative office. Ball valve (2) Three-way change valve While the air compressor is running, strainer is Ⓔ...
⑭ M ake sure no oil leaks from the oil drain valve and clogging of the oil strainer and a fire. plugs. ● Be sure to use genuine Hitachi GL-68 DSP compressor. Absolutely DO NOT mix different types of lubricating oil.
4.4 Cleaning of Oil Strainer (Primary Side) (Bi-Annually) ① Drain the lubricating oil in the procedure described in page 23. ② Remove the front door (1) [Ref. No. 904] and left door [Ref. No. 991]. ③ Remove the strainer cover. Then remove the oil strainer and clean it.
4.6 Operation Check of Air Relief Valve (Bi-Annually) ① Maintain the rated maximum discharge pressure (ex. 100psi(0.70MPa)). Relief valve ring [Rear view] ② P ull the ring connected to air relief valve. ③ Verify that the air relief valve operates properly and get a hand off of the ring.
③ Generally, there are 3 kinds of dust and dirt particles. ・ Light dust particles ・ Heavy dust particles ・ Greasy dust particles Contact the local HITACHI distributor/master Rear panel (3) Rear panel (2) Rear panel (1) dealer or representative office for the detail.
4.9 Replacement of Check Valve (2-Yearly) Depressurizing the System Air-Cooled ① Discharge the compressed air in the procedure in Gasket (1) page 20. Gasket (2) Removing the Enclosure Panels Check valve cover (upper) Remove the enclosure panels, such as front door (1) Gasket [Ref.
③ Close the front door. IMPORTANT ● Contact the local HITACHI distributor/master dealer or representative office for the grease detail. ● Greasing must be done while the main motor The bearing on the opposite side is shield type; filling operating.
◎ ◎ ◎ ○ Burnt motor coil NOTE 2 ◎ ◎ ◎ ○ Contact the local Hitachi distributor. ○ ○ ○ NOTES) 1. ◎ : Close relationship between the cause and type of problem. 〇 : Relationship between the cause and type of problem.
4.12 Maintenance of Oil Mist Remover 1. Replacement of remover element 3. Maintenance of Relief Valve (See Fig. A.) ① Remove the pipe provided at the top of the remover ① T urn the nut at the top of the relief valve and remove if required.
Confidential to Customer 4.13 Maintenance of Cooling fan and cooling fan motor A picture and a drawing below indicate the structure of the cooling fan, fan motor and their fastening. Cooling fan and fan motor is fastened by the left hand screw (L-bolt). Take care so that cooling fan is not damaged when it is removed from the air compressor.
Confidential to Customer 4.14 The procedure to attach the motor cover Water-Cooled (1) Fixed the thermostat on the DE side of end bracket. Treat the cable with particular caution. The temperature sensing Be sufficiently careful not to portion is brazed into the damage the temperature sensor.
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Confidential to Customer (3) Fix the motor cover 1 and 2 to the motor cover fixing bracket by M6 bolt and motor eyebolt. 55kW Motor Cover 2 Notch Motor Cover 1 Pull out the temperature sensor Motor eyebolt Temperature Rubber Bush Sensor 5×M6-25 Be sufficiently careful not to...
Confidential to Customer 4.15 Maintenance of Oil Pump 4.15.1 Removal from the Gear Case Outer Rotor Remove the oil piping from the oil pump. Then, detach Inner Rotor the oil pump from the gear case. (When detaching the Inner Key Snap Ring oil pump, be careful not to damage the gear.) Housing...
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Confidential to Customer 4.15.3 Cleaning and Checking ① Clean the oil pump body, inner rotor, outer rotor, ③ Attach the inner key to the pump side of the shaft. and bearing housing. Then check the sliding Then fit the inner rotor and the outer rotor in this sur faces of the components.
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Confidential to Customer ■ Oil Pump Model ■ Tool Air-Cooled Fix speed type 50Hz : TOP-N340FAM Fix speed type 60Hz/ Vtype : TOP-N330FAM Water-Cooled ALL : TOP-N320FA ■ Replacement Parts When re-assembling, the parts shown in Table 1 must be replaced with new ones. Fig.
Confidential to Customer 4.16 Maintenance of Suction Throttle Valve Unloader Body Air Intake Duct 4.16.1 Removing the Suction Throttle Blowoff Valve Assembly Air Cylinder Silencer Assembly ① Remove the air intake filter. See the air intake filter maintenance manual for details. ②...
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Confidential to Customer 4.16.2 Disassembling the Air Cylinder ③ Mark the matching position along the circumference ⑨ Remove the backup ring (F28), and pull out air of the air cylinder. cylinder cover 1 (504), cover 2 (505) from both sides of air cylinder tube (503).
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Confidential to Customer 4.16.3 Cleaning and Checking ① Clean the STV body. In particular, sand the valve ② Fit seal packing (3) (518) to piston (517). Then seat surface with sandpaper until the machining attach air cylinder piston gasket (537) to spindle surface is visible.
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Confidential to Customer ⑦ Attach valve plate (C) (515), spacer (542), and valve ⑩ Attach air cylinder packing (511) to the STV body, plate (A) (514) in this order to the STV body of the and then mount the air cylinder assembly. Check the air cylinder.
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Confidential to Customer ■ Replacement Parts When re-assembling, the parts shown in Table 1 must be replaced with new ones. Table 1 Air cylinder replacement parts list Valve sheet of blowoff valve piston O-ring (2) 40615070 × 1 40615490 × 2 Fluorine-containing rubber Fluorine-containing rubber A : 1.97inch(50mm)
Confidential to Customer 4.17 Oil Pump motor and Airend removal 4.17.1 Oil Pump motor removal Drain the lubricating oil from the gear case. After that, disconnect the oil piping and remove the oil pump from the gear case. (When removing the oil pump, be careful not to damage the gear.) Oil Pump 4.17.2 Airend removal...
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Confidential to Customer ① Be sure to remove the Cap nut (313), O-ring (311), Fitting (312) and Oil nozzle (320) from gear casing (301) before removing the airends.; Fig. 4.17.2 (1). WARNING Complete removal of the Oil nozzle (320) and associated components is necessary to prevent damage during the airends removal.
Confidential to Customer 4.18 Oil casing and Gear casing removal 4.18.1 Oil casing removal ① Attach a eyebolt (M12), and hoist the oil casing. ② Remove the bolt, and detach the oil casing. Oil casing weight ; 73 lbs (33 kg) 4×...
Confidential to Customer 4.19 Main motor removal Prepare the additional 2×M16 eyebolts for this procedure. 55kW Motor Weight : 864 lbs (392 kg), 4.19.1 Main motor removing for the fixed speed type. 75kW Motor Weight : 1186 lbs (538 kg) ①...
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Confidential to Customer 55kW Motor Waight 441lbs (200 kg), 4.19.2 Main motor removal for the Vtype. 75kW Motor Waight 507 lbs (230 kg) ① With hanging the motor by using a two motor eyebolts, remove the 8×M16-45 bolt for the gear casing and shaft seal cover, and remove the 2×M16-60 for the motor and base plate ②...
Confidential to Customer 4.20 Replace the Bushing 4.20.1 Main motor removal (Ref. 4.19 Main motor removal) 4.20.2 Oil pump motor removing (Ref 4.17 Oil Pump motor and Airend removal) 4.20.3 Oil pump gear shaft removal Oil Pump Gear Shaft ① Remove the 6×M10 bolts. ②...
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Confidential to Customer 4.20.5 Bushing replacement ■ Removal procedure ① Loosen the 10×M16 bolts and remove the shaft seal cover from the main motor. ② Remove the 4×M8 flat head bolt. For the Vtype, remove the M6 set screw. ③ Remove the bushing, O-ring (inside) and collar together by using the general pulley remover.
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Confidential to Customer 4.20.6 Attach the bull gear ① Attach the key. Bull gear Gear retaining plate ② Apply the anti seizing paste between the motor shaft and the bull gear. Anti seizing paste shall be the molybdenum disulfide basis. ③...
Confidential to Customer 4.21 Pinion Gear Replacement Procedure 4.21.1 Removing the Air End Remove the air end. see p. 43 “4.17 Oil Pump motor and Airend removal” 4.17.2 Airend removal) 4.21.2 Pulling Out the Pinion Gear Attach the pinion gear pull-out tool. When attaching Max Oil Pressure the tool, ensuring that the O-ring is not stuck.
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Confidential to Customer ■ Tool (1) Dimensions of the removing tool dimension • 1st-stage side Part code No : 59031290 1. Thermal refining required (quenching at 850°C to 950°C(1562℉ to 1742℉), Material : SCM415H (mm) tempering at 550°C to 650°C(1022℉ to 1202℉)) Hardness: HRC 32 to 40 PS1/4, 15 deep 2.
Replacement Battery replacement display on LCD monitor criteria Approx. 1 year with power off Life Approx. 6 years under ordinary service conditions ● The batteries is an exclusive part. Contact the local HITACHI distributor/master dealer or representative office.
Confidential to Customer 4.23 Inspection of Thermistor and Pressure Sensor If the thermistor or pressure sensor shows any sign of failure during operation, replace the part in accordance with the part name listed below. Table 1 Thermistor/pressure sensor part name list Code Sensor type Remarks...
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Confidential to Customer ■ Sensor position for air-cooled type [Fixed speed type] ■ Connection position on the PCB side LCD PCB side CPU PCB side (See the back side of instrument panel.) (control panel side) CN10 CN16 (From TH2) (From PS2) CN13 CN11 (From TH3)
5. PARTS LIST Air End Assembly Ref. Description 100 1st-Stage Air End (new) 132 1st-Stage Air End Discharge Cover 133 1st-Stage Air End Jacket Cover 134 Gasket, 1st-stage air end discharge cover 135 Gasket, 1st-stage air end jacket cover 138 Knock pin, 1st-stage air end 143 Pinion Gear, 1st-stage air end 200 2nd-stage Air End (new) 232 2nd-Stage Air End Discharge Cover...