2.5.1 Basics of the Screw Compressor
The screw compressor is a positive displacement rotary compressor. As shown in Figure 2-3 Compressor Mechanism, the refrigerant (gas) is continuously compressed by changing the volume between the casing and the male and female meshed screw rotors, which have different profiles. The rotor with 4 protruding lobe sections is called the M rotor (male rotor), and the rotor with 6 lobe depressions is called the F rotor (female rotor). Throughout this manual they are referred to as the M rotor and F rotor. The compressor M rotor shaft is driven by the two-pole or four-pole motor via the speed increaser gear.

2.5.2 Suction Process
As shown in Figure 2-4 Suction Process, the rotors’ different profiles mesh together. Also the volume enclosed between the M and F rotor lobes and compressor casing increases from the suction side as the rotors turn. As rotations continue, at a certain point the volume reaches its maximum, the rotors start to trap the gas between the lobes and compressor casing thereby isolating the gas from the suction port.

Figure 2-4 Suction Process
2202L5JE-DA-C5-N_2015.05.2 Compressor Specifications and Structure Compound 2-stage Screw Compressor 2.5 Mechanisms 1612LSC Speed Increaser Type 2-7

2.5.3 Compression Process
As the rotors further rotate, the sealing line between them moves toward the discharge side and the volume between the rotor lobes decreases and compresses the trapped gas. Figure 2-5 Compression Process Figure 2-6 Discharge Process

2.5.4 Discharge Process
Through the compression process, the volume between rotor lobes decreases to a predetermined value at the discharge port. Following rotor rotation, the compressed refrigerant gas is pushed out of the discharge port.

2.5.5 About Volume Ratio (Vi)
Volume ratios (Vi) of C-series screw compressors are indicated in performance tables or catalogs by using port symbols L and M. The volume ratio represented by each symbol is as follows: L=2.63, M=3.65.
Which volume ratio (L or M) should be used is decided according to operating conditions. If the compressor is used with a volume ratio that does not match operating conditions, operation will go inefficiently wasting the power. The relationship between volume ratios and generally used compression ratios is as follows: (Vi) κ= πi = Pd/Ps κ= Cp/Cv of refrigerant gas Vi = designed volume ratio πi = designed compression ratio The constant of the refrigerant gas also a factor, and the Vi value for the compression ratio will change according to the refrigerant gas used.

Figure 2-7 Volume Ratio Explanation
2202L5JE-DA-C5-N_2015.05.2 Compressor Specifications and Structure Compound 2-stage Screw Compressor 2.5 Mechanisms 1612LSC Speed Increaser Type 2-8
(A) When Vi matches operation conditions The required compression ratio and Vi are both low The required compression ratio and Vi are both high
(B) When Vi does not match operation conditions Vi is too low compared to the required compression ratio Vi is too high compared to the required compression ratio Figure 2-8 Relationship between volume ratio (Vi) and operation conditions 2202L5JE-DA-C5-N_2015.05.2 Compressor Specifications and Structure Compound 2-stage Screw Compressor 2.5 Mechanisms 1612LSC Speed Increaser Type 2-9

2.5.6 Capacity Control Mechanism
The capacity control structure involves the moving of a slide valve, bypassing suction gas just before compression on the suction side, which shortens the portion of the rotor used for compression. The slide valve is at the bottom of the casing where the rotors mesh together, and is constructed to move parallel to the rotor’s axis. This movement is changed by a cam mechanism into rotation movement, and as the position (capacity control ratio) is indicated externally, the electrical resistance value changes to provide feedback to the automatic control circuit.

Figure 2-9 Capacity Control Mechanism
The 1612LSC speed increaser type has capacity control on the low-stage block only. 2.5.7 Bearings and Balance Piston For the load created on the rotor perpendicular to the axle, a white metal-lined sleeve-type bearing is used. The bearing uses surface fitted ball bearings with angular contact for loads along the axis direction. In particular, axial load for the M rotor, which has one type of helical gear, is comparatively larger than that of the F rotor because of the thrust load from discharge pressure. This load for the M rotor is reduced by the use of a thrust bearing, along with a balance piston providing opposing hydraulic pressure.

2.5.8 Shaft Seal
To prevent refrigerant gas and oil leakage, a reliable mechanical seal assembly is used for the shaft seal of the speed increaser gear spindle. Mechanical seal assembly is mainly composed of "rotating ring" installed on the rotor shaft and "stationary ring" installed in the seal cover. Rotating ring rotates with the shaft, and slides each other with the stationary ring while maintaining a micron class gap. The sliding each other place is called as the sliding surface. As an example, for the BBSE (Balanced Bellows Single Seal)-type, which is a standard seal currently in use, the fixed ring (mating ring) is cast iron, and the rotating ring is carbon, with an O-ring for the packing.

Figure 2-10 Slide Valve in the
Rotor Casing 2202L5JE-DA-C5-N_2015.05. 2 Compressor Specifications and Structure Compound 2-stage Screw Compressor 2.6 Gas and Oil Flow 1612LSC Speed Increaser Type 2-10 2.6 Gas and Oil Flow The screw compressor’s compression process is described earlier in this manual. Gas for the compound speed increaser type 1612LSC compressor passes from the evaporator and through the suction strainer and check valve, and is sucked into the center part of the compressor ①, and it is compressed at the low-stage ② .Then the compressed gas is discharged at ③. ③ and ④ are connected by piping through which gas used for super cooling is mixed in from the liquid cooler. Lubricating oil injected at the low-stage is, while kept mixed with gas, suctioned from ④ into the high-stage. After being compressed at ⑤, the gas mixed with lubricating oil is discharged from ⑥ to the oil separator, and then sent to the condenser. The oil is cooled even without intermediate gas cooling, so the high-stage discharge temperature can be maintained at below 90 °C. Oil Supply Route Lubricating oil is split into 4 flows as shown in Figure 2-12, and after providing lubrication, it is mixed with discharge gas and leaves the compressor. In standard configurations, oil injection is not performed at the high-stage.

 

5.2 Maintenance and Inspection List

5.2.1 Daily Management
As daily management, check the items listed in Table 5-1 "Daily Inspection Items" and record the results. Logging these operation data on a daily basis aid in finding out any abnormal conditions of the
compressor. This is significantly effective in preventing compressor failures. It is particularly important to check whether the temperature/pressure correlations related to the refrigerant evaporation and condensation is proper. This makes it possible to quickly find out problems in the compressor or the system. If a failure or accident should occur in the compressor or the system, the operation logbook will help determine the cause and take prompt and proper actions.

Daily Maintenance Items

1. Lubrication oil level
When the oil level in the oil separator reaches the lower limit, charge lubricating oil by referring to the instruction manual of the unit.

2. Replacing oil filter element
When the differential pressure between the inlet and out let ports of the oil filter exceeds 0.1 MPa, replace the oil filter element. At the beginning of the operation, the differential pressure of the oil filter may increase quickly.

3. Cleaning of suction strainer
When the compressor operating hours exceeds 500, check the suction strainer. If a temporary filter is installed for the initial stage of operation, remove it. At the beginning of the operation or after periodical check, the differential pressure between the front and back of the suction strainer may increase quickly. If the differential pressure becomes large, check and clean the suction strainer.

4. Lubricating oil leak rate from mechanical seal
If much oil leaks from the mechanical seal, determine the leak rate per hour. The following table shows guidelines for allowable leak rate and the rate at which inspection must be done. If any problem (damage, etc.) is found in mechanical seal, replace the mechanical seal.

5. Contamination on the cooling water side of the cooling pipes of condenser and oil cooler
Clogging and contamination of the cooling pipe is largely affected by the quality of cooling water. When the oil temperature and discharge pressure gradually rise during the initial stage of operation, inspect and clean the cooling water side of oil cooler and condenser even when the time has not yet come at which inspection must be done.

 

 

P/N Part name Part code No. Remarks Quantity 52/62 53/63 54
1-1 Main Rotor Casing (1) CS00100-160L 160L** 1 1 -
1-2 Main Rotor Casing (2) CS00100-1612C 1612*SC 1 1 1
2-1 Hexagon Socket Head Cap Screw NB35412-040 M12×40 52 52 52
2-2 Hexagon Socket Head Cap Screw NB35414-040 M14×40 36 36 36
3-1 Alignment Pin NE2013-040 Φ13×40 4 4 4
3-2 Alignment Pin NE2016-040 Φ16×40 4 4 4
4-1 Hanger Bolt NB600-16 M16 1 1 1
4-2 Hanger Bolt NB600-12 M12 1 1 1
5-1 Suction Cover (1) CS00500-1612C1 1612**C 1 1 1
5-2 Suction Cover (2) CS00500-1612C2 1612**C 1 1 1
6-1 Gasket, Suction Cover (1) CS00600-160N 160*** 1 1 1
6-2 Gasket, Suction Cover (2) CS00600-1612CN 1612**C 1 1 1
8 Spring Pin NE3204-010 Φ4×10 4 4 4
10-1A Plug NF06-010 R3/8 1 1 1
10-2A Plug NF06-008 R1/4 1 1 1
10-2B Plug NF06-010 R3/8 1 1 1
11-1 Bearing Head (3) CS01100-1612C3 1612**C 1 1 1
11-2 Bearing Head (2) CS01100-1612C2 1612**C 1 1 1
12-1 Gasket, Bearing Head (1) CS01200-160N 160*** 1 1 1
12-2 Gasket, Bearing Head (2) CS01200-1612CN 1612**C 1 1 1
13 Hanger Bolt NB600-12 M12 1 1 1
14 Spring Pin NE3204-010 Φ4×10 4 4 4
15-1A Plug NF06-004 R1/8 1 1 1
15-1B Plug NF06-004 R1/8 1 1 1
15-1C Plug NF06-015 R1/2 1 1 1
15-1D Plug NF06-020 R3/4 1 1 1
17-2 Gasket, Bearing Cover (2) CS01700-1612CN 1612**C 1 1 1
18-1 Hexagon Socket Head Cap Screw NB35414-040 M14×40 24 24 24
18-2 Hexagon Socket Head Cap Screw NB35412-040 M12×40 26 26 26
19-1 Alignment Pin NE2013-040 Φ13×40 2 2 2
19-2 Alignment Pin NE2013-040 Φ13×40 2 2 2
20 Spring Pin NE3203-010 Φ3×10 1 1 1
21 Plug NF06-004 R1/8 1 1 1
22 Balance Piston Cover CS02200-1612C 1612**C 1 1 1
23 Gasket, Balance Piston Cover CS02300-1612CN 1612**C 1 1 1
24 Hexagon Socket Head Cap Screw NB35410-035 M10×35 12 12 12
25-1 Male Rotor (1) CS02500-1612C1N 1612LSC speed increaser type 1 1 1
26-1 Female Rotor (1)
25-2 Male Rotor (2) CS02500-1612C2N 1612LSC 1 1 1
26-2 Feale Rotor (2)
27-1A Main Bearing /Side Bearing (1) A CS02700-1612C3 1612LSC speed increaser type 1 1 1
27-1B Main Bearing /Side Bearing (1) B CS02800-1610C1 1610SLC/1612**C 1 1 1
27-2 Main Bearing (2) CS02700-125 125*** 2 2 2
28-1 Main Bearing /Side Bearing (1) CS02800-1610C1 1610SLC/1612**C 2 2 2
28-2 Side Bearing (2) CS02800-125 125*** 2 2 2
29-1A Snap Ring (1) C type Internal NG11-112 H112 1 1 1
29-1B Snap Ring (1) C type Internal NG11-102 H102 3 3 3
29-2 Snap Ring (2) C type Internal NG11-080 H80 4 4 4
30 Balance Piston CS03000-1612C 1612**C 1 1 1 2202L5JE-DA-C5-N_2015.05.7 Related Documents

Compound 2-stage Screw Compressor 7.2 Parts Configuration Table 1612LSC Speed Increaser Type 7-6
P/N Part name Part code No. Remarks Quantity 52/62 53/63 54
31 Key, Balance Piston CS03100-125 125*** 1 1 1
32 Snap Ring C type External NG12-040 S40 1 1 1
33 Sleeve, Balance Piston CS03300-160 160*** 1 1 1
34 Hexagon Socket Head Cap Screw NB35406-015 M6×15 1 1 1
35 O-ring PA12-095 JIS B 2401 G95 1 1 1
37 Snap Ring C type Internal NG11-102 H102 1 1 1
38-1 Thrust Bearing (1) A CS03800-1612CP 7214B 1set 1set 1set
38-1 Thrust Bearing (1) B CS03800-160P 7212B 1set 1set 1set
38-2 Thrust Bearing (2) CS03800-125P 7209B 2set 2set 2set
39-1 Lock Nut (1) A NG31-014 AN14 1 1 1
39-1 Lock Nut (1) B NG31-012 AN12 2 2 2
39-2 Lock Nut (2) NG31-009 AN09 2 2 2
40-1A Lock Washer (1) A NG32-014 AW14 1 1 1
40-1B Lock Washer (1) B NG32-012 AW12 2 2 2
40-2 Lock Washer (2) NG32-009 AW09 2 2 2
41-1 Spacer, Thrust Bearing Outer Race (1) CS04100-160 160*** 1 1 1
41-2 Spacer, Thrust Bearing Outer Race (2) CS04100-125 125*** 2 2 2
42-1A Spacer, Thrust Bearing Alignment (1) CS04200-1612C 1612LSC speed increaser type 1 1 1
42-1B Spacer, Thrust Bearing Alignment (1) CS04200-B160 160*** Booster 1 1 1
42-2 Spacer, Thrust Bearing Alignment (2) CS04200-125 125*** 2 2 2
43-1A Thrust Bearing Gland (1) A CS04300-1612C3M 16LSC speed increaser type 1 1 1
43-1B Thrust Bearing Gland (1) B CS04300-1612C3F 1 1 1
43-2A Thrust Bearing Gland (2) A CS04300-1612C2F 1612**C 1 1 1
43-2B Thrust Bearing Gland (2) B CS04300-1612C2M 1612**C 1 1 1
45-1A Hexagon Head Bolt NB15512-035 M12×35 4 4 4
45-1B Hexagon Head Bolt NB15510-030 M10×30 4 4 4
45-2 Hexagon Head Bolt NB111008-030 M8×30 8 8 8
46-1A Spring Washer ND320-012 M12 4 4 4
46-1B Spring Washer ND320-010 M10 4 4 4
46-2 Spring Washer ND320-008 M8 8 8 8
48 Retainer, Oil Seal CS04800-160 160*** 1 1 1
49 O-ring PA12-090 JIS B 2401 G90 1 1 1
50 Oil Seal CS05000-160VD SA1J55 × 70 × 9 1 1 1
51 Seal Cover CS05100-160 160*** 1 1 1
52 Gasket, Seal Cover CS05200-160N 160*** 1 1 1
53 Hexagon Socket Head Cap Screw NB35408-025 M8×25 8 8 8
54 Unloader Slide Valve (L Port) CS05400-1612C 1612LSC 1 1 1
54 Unloader Slide Valve (M Port) - 1612LSC 1 1 1
58 Hexagon Socket Head Cap Screw NB35408-030 M8×30 4 4 4
59 O-ring PA11-016 JIS B 2401 P16 1 1 1
60 Unloader Cylinder CS06000-1612C 1612**C 1 1 1
61 Hexagon Socket Head Cap Screw NB35408-095 M8×95 8 8 8
63 O-ring PA12-095 JIS B 2401 G95 1 1 1
64 Unloader Piston CS06400-1612C 1612**C 1 1 1
65 O-ring PA11-075 JIS B 2401 P75 1 1 1
66 Cap Seal CS06600-125 CAP-1BE75 1 1 1
67 Push Rod (3), Unloader Slide Valve CS06700-1612C3 16LSC speed increaser type 1 1 1
68 Guide Pin NE2503-008 Φ3×8 1 1 1
69 Lock Nut NG31-005 AN05 1 1 1
70 Lock Washer NG32-005 AW05 1 1 1
71 Lock Nut NG31-006 AN06 1 1 1
72 Lock Washer NG32-006 AW06 1 1 1
73 O-ring PA11-021 JIS B 2401 P21 1 1 1
74 Unloader Cover CS07400-125S 125*** 1 1 12202L5JE-DA-C5-N_2015.05.7 Related Documents

Compound 2-stage Screw Compressor 7.2 Parts Configuration Table 1612LSC Speed Increaser Type 7-7
P/N Part name Part code No. Remarks Quantity 52/62 53/63 54
75 O-ring PA12-085 JIS B 2401 G85 1 1 1
76 Hexagon Socket Head Cap Screw NB35406-035 M6×35 8 8 8
77 Indicator Cam CS07700-1610C 1610SLC 1 1 1
78 Ball Bearing CS07800-200 #6000 1 1 1
79 Snap Ring C type External NG12-010 S10 1 1 1
80 Bearing Gland CS08000-200 200*** 1 1 1
81 Hexagon Socket Head Cap Screw NB35406-015 M6×15 3 3 3
82 V-ring CS08200-200B 20×10×12 1set 1set 1set
83 Spring CS08300-200 200*** 1 1 1
84 Retainer, Indicator Cam Spring CS08400-200 200*** 1 1 1
85 Oil Injection Pipe CS08500-160SUK 125L**/160S** 1 1 1
86 O-ring PA11-016 JIS B 2401 P16 1 1 1
87 Guide Block CS08700-160 160*** 1 1 1
88 Stem, Guide Block " 160*** 1 1 1
89 O-ring PA11-016 JIS B 2401 P16 2 2 2
91 Shaft Key (Coupling Key) CS09100-160 160*** 1 1 1
92-1 Suction Flange (1) CS71400-125 MYK 125A (5") 1 1 1
92-2 Suction Flange (2) CS71400-080 MYK 80A (3") 1 1 1
93-1 Gasket, Suction Flange (1) CR72000-125N MYK125A (5") 1 1 1
93-2 Gasket, Suction Flange (2) CR72000-080N MYK 80A (3") 1 1 1
94-1 Hexagon Head Bolt NB12020-055 M20×55 8 8 8
94-2 Hexagon Head Bolt NB12020-055 M20×55 4 4 4
95-1 Discharge Flange (1) CS71400-080 MYK 80A (3") 1 1 1
95-2 Discharge Flange (2) CS71400-065 MYK 65A (2"1/2) 1 1 1
96-1 Gasket, Discharge Flange (1) CR72000-080N MYK 80A (3") 1 1 1
96-2 Gasket, Discharge Flange (2) CR72000-065N MYK 65A (2"1/2) 1 1 1
97-1 Hexagon Head Bolt NB12020-055 M20×55 4 4 4
97-2 Hexagon Head Bolt NB12010-055 M16×55 4 4 4
100 Mechanical Seal Assembly CS10000-160BT BOS-T1 160V** 1set 1set 1set
100 Mechanical Seal Assembly CS10002-160EBS BBS-E 160 1set 1set 1set
120 Unloader Indicator Assembly CS12000-1612F 1612LSC 1set 1set 1set
151 Driven Sleeve 1610**C 1 1 1
152 Drive Hub 1610**C 1 1 1
153 Driven Hub 1612**C 1 1 1
154 Stopper, Drive Sleeve 1610**C 2 2 2
155 Stop Ring RR-293(#10 用) 4 4 4
157 Key, Driven Hub 1 1 1
158 Key, Drive Hub 1 1 1
159 Set Screw NA83606-015 M6×15 1 1 1
160 Lock Nut NG31-008 AN08 1 1 1
161 Lock Washer NG32-008 AW08 1 1 1
162 Hexagon Socket Head Cap Screw NB35406-035 M6×35 5 5 5
163 O-ring PA12-025 JIS B 2401 G25 1 1 1
164 Retainer, Oil Injection Pipe CS16400-1612C 1 1 1
165 O-ring PA11-021 JIS B 2401 P21 1 1 1
166 Hexagon Socket Head Cap Screw NB35406-025 M6×25 4 4 4
168 Pipe Guide, Oil Injection CS16800-1612C 1612LSC 1 1 1
169 Speed Increaser Gear Casing CS16900-1610C 1610SLC 1 1 1
170 Gasket, Speed Increaser Gear Casing CS17000-1612CN 1612LSC 1 1 1
171 Speed Increaser Gear Casing Cover CS17100-1610C 1610SLC 1 1 1
172 Gasket, Speed Increaser Gear Casing Cover CS17200-1610CN 1610SLC 1 1 1
174-1 Speed Increaser Drive Gear (4P) CS17400-1610C52 52-2610rpm 62-3150rpm 1 - --2202L5JE-DA-C5-N_2015.05.7 Related Documents

Compound 2-stage Screw Compressor 7.2 Parts Configuration Table 1612LSC Speed Increaser Type 7-8
P/N Part name Part code No. Remarks Quantity 52/62 53/63 54
174-2 Speed Increaser Drive Gear (2P) CS17400-1612153 53-3610rpm 63-4350rpm - 1 -
174-3 Speed Increaser Drive Gear (2P) CS17400-1612154 54-4350rpm - - 1
175 Key, Speed Increaser Gear Shaft CS18000-1610CD 1610C 1 1 1
176 Gland, Speed Increaser Gear CS18100-1610CD 1610C, 4P 2 - -
179-1 Speed Increaser Driven Gear (4P) CS17900-1610C52 52-2610rpm 62-3150rpm 1 - -
179-2 Speed Increaser Driven Gear (2P) CS17900-1612153 53-3610rpm 63-4350rpm - 1 -
179-3 Speed Increaser Driven Gear (2P) CS17900-1612154 54-4350rpm - - 1
180 Key, Speed Increaser Driven Gear CS18000-1610CI 1610C 1 1 1
181 Gland, Speed Increaser Driven Gear CS18100-1610CIB 1610C, 4P 2 - -
183 Side Bearing Speed Increaser Driven Gear CS02700-125 125*** Main bearing 1 1 1
184 Spring Pin NE3204-010 Φ4×10 1 1 1
185 Roller Bearing, Speed Increaser Driven Gear Spindle CS18500-1612C NU2212 1 1 1
186 Snap Ring C type Internal NG11-110 H110 1 1 1
187 Snap Ring C type External NG12-060 S60 1 1 1
188 Speed Increaser Gear Spindle CS18800-1612C 1 1 1
189 Thrust Bearing CS03800-200 200*** 1set 1set 1set
190 Gland, Thrust Bearing CS19000-1610C 1 1 1
191 Hexagon Head Bolt NB111012-035 M12×35 4 4 4
192 Conical Spring Washer CS04600-200 M12 4 4 4
193 Lock Nut NG31-013 AN13 1 1 1
194 Lock Washer NG32-013 AW13 1 1 1
195 Hexagon Socket Head Cap Screw NB35412-040 M12×40 21 21 21
196-1 Oil Flow Control Throttle CS19600-M408 M4×8×Φ1.5 1 1 1
196-2 Oil Flow Control Throttle R1/8×Φ1.5 2 2 2
197 O-ring PA11-032 JIS B 2401 P32 1 1 1
237-1A Torsional Slip Washer (1) A CS23700-1612CB 1612**C 1 1 1
237-1B Torsional Slip Washer (1) B CS23700-160 160*** 2 2 2237-1 C Torsional Slip Washer (1) C CS23700-200 200*** 1 1 1237-1D Torsional Slip Washer (1) D CS23700-250 250*** 1 1 1
237-2 Torsional Slip Washer (2) CS23700-125 125*** 2 2 2
250-1 Thrust Washer CS25000-1612C3 1612LSC speed increaser type 1 1 1
267 Special Spring Washer ND330-08 M8 4 4 4326 Gland, O-ring CS32600-1612C 1612LSC speed increaser type 1 1 1
335 Special Spring Washer ND330-06 M6 1 1 1
456 Hexagon Socket Head Cap Screw NB35405-010 M5×10 4 4 4
605-1 Plug NF06-015 R1/2 1 1 1
605-2 Plug NF06-008 R1/4 1 1 1
607 Plug NF06-004 R1/8 1 1 1

The part code of the O-ring is the one assigned to NBR which is standard material. When the material of the O-ring is other than NBR, a different part code is used for each material. If you are using O-rings made from other than the standard material, please contact Mayekawa when placing an order. 2202L5JE-DA-C5-N_2015.05. 7 Related Documents

Compound 2-stage Screw Compressor 7.3 Tightening Torques for Bolts and Nuts
1612LSC Speed Increaser Type 7-9
7.3 Tightening Torques for Bolts and Nuts
7-2 List of Tightening Torques

Hexagon socket head cap screw
P/N Tightening point Tightening torque Qty. Size N·m kgf·cm
2-1 Main Rotor Casing (1) to Suction Cover (1) and Bearing Head (1) 90 900 52 M12×40
2-2 Main Rotor Casing (2) to Suction Cover (2) and Bearing Head (3) 140 1400 36 M14×40
18-1 Speed increaser gear casing to Bearing Head (3) 140 1400 24 M14×40
18-2 Bearing Head (2) to Speed Increase Gear Casing 90 900 26 M12×40
24 Balance Piston Cover to Suction Cover (2) 50 500 12 M10×35
34 Balance Piston Sleeve 10 100 1 M6×15
53 Seal Cover to Speed Increaser Gear Casing Cover 25 250 8 M8×25
58 Unloader Slide Valve Unloader Slide Valve (2) 25 250 4 M8×30
61 Unloader Cylinder to Speed Increaser Gear Casing 25 250 8 M8×95
76 Unloader Cylinder Cover to Unloader Cylinder 10 100 8 M6×35
81 Bearing Gland 10 100 3 M6×15
162 Push rod, Unloader Slide Valve 10 100 5 M6×35
166 Oil Injection Pipe Gland 10 100 4 M6×25
195 Speed Increaser Gear Casing Cover to Speed Increaser Gear Casing 90 900 21 M12×40
456 O-ring Gland to Bearing Head (3) 6 60 4 M5×10

Hexagon head screw
P/N Tightening point Tightening torque Qty. Size N·m kgf·cm
45-1A Thrust bearing gland (1) M 50 500 4 M12×35
45-1B Thrust bearing gland (1) F 40 400 4 M10×30
45-2 Thrust bearing gland (2) 30 300 8 M8×30
94-1 Suction cover flange (1) MYK125A 140 1400 8 M20×55
94-2 Suction cover (intermediate piping) flange (2) MYK80A 140 1400 4 M20×55
97-1 Discharge cover (intermediate piping) flange (1) MYK80A 140 1400 4 M20×55
97-2 Discharge cover flange (2) MYK65A 110 1100 4 M16×55
191 Thrust bearing gland ( speed increaser gear spindle) 50 500 4 M12×35 2202L5JE-DA-C5-N_2015.05. 7 Related Documents

Compound 2-stage Screw Compressor 7.3 Tightening Torques for Bolts and Nuts
1612LSC Speed Increaser Type 7-10

Locknut P/N Tightening point Tightening torque N·m Regular Qty. Size use Maximum
39-1A Thrust bearing (1) M 656 820 1 AN14
39-1B Thrust bearing (1) F Speed increaser driven gear 408 510 2 AN12
39-2 Thrust bearing (2) 206 258 2 AN09
69 Unloader piston 80 — 1 AN05
71 Unloader slide valve 49 61 1 AN06
160 Intermediate gear coupling, drive hub 90 113 1 AN08
193 Thrust bearing, speed increaser gear 522 653 1 AN13
269 Speed increaser drive gear 1186 1483 1 AN17

Note: When tightening a lock nut, if it is difficult to use a torque wrench, manage the tightening torque of the lock nut controlling the tightening angle range as explained below.

Tightening Angle Range of Lock Nuts for Rotors
a) After tightening the lock nut by hand, further tighten the lock nut by using a lock nut wrench until the rotor starts to turn. Take care not to over-tighten.
b) Put a mark on the lock nut at the right side edge of the rotor groove where the stopper tongue of the lock washer fits in, as shown in Figure 7-9.
c) From this marking position, tighten the lock nut in such a way that rotation can be stopped within the tightening angle range shown in Table 7-3 (2016**C【39-1】,【39-2】and【160】: 30° to 40°(first time tightening), 20° to 30°(second time tightening). When measuring the angle, use an angle gauge which is set to the diameter of rotor shaft.

Table 7-3 Tightening Angles Specified for Lock Nuts of Rotor
* When tightening lock nut, tightening start position differs between the first time tightening and the tightening for the second time or after. Therefore, angle ranges are specified also for the second time tightening.

Figure 7-11 Position where mark is put
Angle Gauge (example) Model Angle range First time tightening 125 to 250 30° to 40° Second time Marking tightening 125 to 250 20° to 30° Rotor groove (slot) where stopper tongue of the lock washer fits 2202L5JE-DA-C5-N_2015.05.

Compound 2-stage Screw Compressor 7.4 O-rings for Use 1612LSC Speed Increaser Type 7-11
7.4 O-rings for Use
7.4.1 List of O-rings for Use Table 7-4 List of O-rings for Use P/N Used locations JIS-B2401 attached place description in function aspect (mm type)
35 Balance Piston Sleeve same as left G95
49 Oil Seal Retainer same as left G90
59 Oil Injection Pipe Guide Oil Injection Pipe P16
63 Speed Increaser Gear Casing Unloader Cylinder G95
65 Unloader Piston same as left P75
73 Unloader Push Rod Unloader Piston P21
75 Unloader Cover same as left G85
86 Oil Injection Pipe same as left P16
89 Guide Block Stem same as left P16
163 Special specification only for the LLC
type, Guide Block Stem same as left G25
165 Unloader Slide Valve (1) same as left P21
197 Bearing Head (3) Unloader Push Rod P32
7.4.2 List of O-ring Materials for Screw Compressor

Table 7-5 List of O-ring Materials for Screw Compressor (except for mechanical seal) Operation fluid O-ring materials Ammonia NBR Hydrofluorocarbon (HFC) Carbon dioxide (CO2) FKM HNBR Triflorofluoromethane (R23) FKM Propane Propylene Natural gas City gas Helium