Bitzer

The widest Screw Range Products Bitzer Screw Compressors Open Drive

- Marine - Ammonia

OS

Semi Hermetic

- Low temp. - Supermarket - Cold room - Industrial refrigeration

HS

Compact Screw

- Chiller

CSH CSW

Hermetic

- Transport - Train A/C

VSK Bitzer Intro_E –

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Today‘s focus...... Bitzer Screw Compressors Open Drive

- Marine - Ammonia

OS

Semi Hermetic

- Low temp. - Supermarket - Cold room - Industrial refrigeration

HS

( external oil separator )

Compact Screw

- Chiller

CSH (built in oil separator) Bitzer Intro_E –

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CSH Compact Screw with Integral Oil Separator High Temperature screw compressors (With built in Motor & Oil separator)

CSH

65 / 75 / 85 / 95 (Max 300HP)

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Screw Compressor Applications CSH Series 4-step Capacity Control

CR SU 25%* 50% 75% 100%

1

2

3

4

Infinite Capacity Control

Multiple Possibilities

CR1

CR2

CR SU

1

2

3

4


25 50  max min

CR3

CR4

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Screw Compressor Applications CSH Series Not advisable for > 2 circuits

+5oC

Water Cooled Liquid Chiller:

1 8

to

 Single Circuit Single Compressor System – The Simplification of Application  Compact

- 15oC

2

4

Bitzer-Software.lnk

3

7

6

5

simplified scheme Bitzer Intro_E –

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SITE VISIT REPORT

Date : Jan 2006

Thailand – Plate Ice Machine - CSH Application : Plate Ice Machine Operating Condition: -10oC SST / 40oC SCT Refrigerant : R22 Output : 25 tons plate ice per day Economizer : No Year Installed : 2005 Compressor : 1 pcs. CSH Bitzer Screw Bitzer Model : CSH 8551-125 x 1 pcs 20 tons per day (CSH 7571-90) Contractor offer 5 years warranty

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Today‘s focus...... Bitzer Screw Compressors Open Drive

- Marine - Ammonia

OS

Semi Hermetic

- Low temp. - Supermarket - Cold room - Industrial refrigeration

HS

( external oil separator )

Compact Screw

- Chiller

CSH (built in oil separator) Bitzer Intro_E –

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Screw Compressor Application Ranges Semi-hermetic Screw Compressors HSK & HSN

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Design of Bitzer HS. Screw Compressor Single housing

CR pistons are absolutely flush with flange & rotor contour

Very large cross sections during CR operation – minimum losses Bitzer Intro_E –

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HS 85 − Transparent View

Integrated oil filter Very solid bearing arrangement

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HS. Screws – Working Principle SL

SL

ECO SU/CR

DL

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Bitzer Screws – Profile & Discharge Port

Male Rotor

Female Rotor

Discharge Port Bitzer Intro_E –

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Application Range of Screw Compressors HSK/HSN with R22

Full Load Operation with & w/o Eco Additional cooling may be required, see Applications Manuals or Selection Software

Contact Freezer Chill water ColdFlake roomIcePlant Machine IQF, Blast freezers Bitzer Intro_E –

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Current Compressor Models – Semi-Hermetic HS..

K

N

HT & MT

LT

Displacement [m3/h @ 50 Hz]

HSK5343-30

HSN5343-20

84

HSK5353-35

HSN5353-25

100

HSK5363-40

HSN5363-30

118

HSK6451-50

HSN6451-40

140

HSK6461-60

HSN6461-50

165

HSK7451-70

HSN7451-60

192

HSK7461-80

HSN7461-70

220

HSK7471-90

HSN7471-75

250

HSK 8551-110

315

HSK 8561-125

359

HSK 8571-140

HSN 8571-125

410 Bitzer Intro_E –

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Screw Compressor Application Ranges

Open Drive Screw Compressors OSK, OSN

& OSKA, OSNA

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Application Range of Screw Compressors OSK/OSN with R22

Full Load Operation with & w/o Eco Additional cooling may be required, see Applications Manuals or Selection Software

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Current Compressor Models – Open Drive OS..

K

N

HT & MT

LT R22 & HFCs

R22 & HFCs

NH3

OSK5343

OSKA5343

OSN5343

OSNA5343

84

OSK5353

OSKA5353

OSN5353

OSNA5353

100

OSK5363

OSKA5363

OSN5363

OSNA5363

118

OSK7441

OSKA7441

OSN7441

OSNA7441

165

OSK7451

OSKA7451

OSN7451

OSNA7451

192

OSK7461

OSKA7461

OSN7461

OSNA7461

220

OSK7471

OSKA7471

OSN7471

OSNA7471

250

OSK 8551

OSKA 8551

315

OSK 8561

OSKA 8561

359

OSK 8571

OSKA 8571

OSN 8571

NH3

Displacement [m3/h @ 50 Hz]

OSNA 8571

410



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Application Range of Open Drive Screws with NH3 Additional Cooling (oil cooler) required With Part Load Operation limited Application Range: see individual envelopes

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Comparison of Discharge Gas Temperatures with Single Stage Operation 260 240

to +5°C, tc 50°C

toh 20°C / *NH 3 ∆ toh 5 K Isentropic Efficiency: HFCs + HCs 0.7 (semi-hermetic) NH3 0.8 (open type compressor)

to -10°C, tc 45°C

Discharge Gas Temperature [°C]

220

to -35°C, tc 40°C

200 outside operating limits

180

outside operating limits

160 140 120 100 80 60 40 20 0 R22

R 134a

R 407C

R404A / R507A

R 410A

R 290

R 600a

R 1270

NH3*

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2-Stage Compressors & Systems Why 2-stage systems?  Low temp. application / very low evaporating temperatures  NH3 low mess flow charateristic will generate very high

discharge temperature at low temperature.  need 2 stage, cascade system or booster systems.

2-stage systems‘s Fact are: - Is a MUST for R22 and NH3 refrigerant with low temp application - Generally increase the system efficiency - become complicated system, need precise control or high risk of failure Bitzer Intro_E –

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Example of 2-Stage Recip Compressor

2 stages – 6 cylinders recips - No unload option

6 cylinders recips - possible 66% / 33% unload

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Systems of 2-stage Reciprocating Compressors incl. Subcooler

Condenser

T CPR

MP

HP

T

Receiver

M

LP Sub Cooler

Evaporator Bitzer Intro_E –

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Cascade System +40oC

Vereinfachte Darstellung Simplified Sketch

-15oC

-40oC

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Application Range of Open Type Screws with NH3 – general overview 60 Additional Cooling

50 tc °C 40

OSKA

OSNA

(oil cooler) requiered

30

With Part Load Operation limited

20

Application Range: see individual

10 0 -10 -20 -50

OSKAB (Booster)

NH3 ∆toh < 10K) (∆

with add. oil pump

-40

envelopes

-30

-20

-10

0 °C

10

to

20 Bitzer Intro_E –

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Einsatzgrenzen R22-Booster ohne Zusatzkühlung Application Limits R22 Booster w/o Additional Cooling 20

tc [°C] Verflüssigungstemperatur Condensing Temp.

10 externe Ölpumpe erforderlich

0

additional oil pump requirerd

-10

HSKB OSKB R22

-20

toh = 10 K -30 -55

-50

-45

-40

-35

-30

-25

to [°C]

-10

Verdampfungstemperatur / Evaporating Temp. vorläufige Werte / preliminary data

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Application Limits 2-stage Reciprocating Compressors 60

tc 50 R22

40 30 R507A Highest COP Low temp 20

R404A R507A

10 toh =20°C

0 -80

-70

-60

-50

-40

-30

-20 to

4.2 Bitzer-Software.lnk

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Booster screw Compressor Models HSKB

OSKB

semi

Open type

HSKB5343-15

OSK(A)B 5341-K

HSKB5353-17

OSK(A)B 5351-K

HSKB5363-20

OSK(A)B 5361-K

R22/R404 or Ammonia NH3

HSKB6451-40 HSKB6461-40 HSKB7451-40

OSK(A)B 7451-K

HSKB7461-40

OSK(A)B 7461-K

HSKB7471-40

OSK(A)B 7471-K

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General Highlights of Bitzer Screw Compressors BITZER HS. Screw Compressors are the result of more than 20 years of experience in research, development, production and application of screw compressors. The latest step in this evolution features:  Wide product range with the least No. of models  Robust & long term proven construction elements  3-step capacity control from smallest to largest model

50% / 75%

 Unique “low pressure bearing chamber”

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HS. Screws – Oil Management with Sealed Low Pressure Bearing Chamber Conditions: R404A / Oil POE 170 cSt SST -10°C / SDT 45°C DGT 80°C (w/o oil cooling)

Bitzer design with sealed bearing chamber: BCP 6.5 bar (abs) Solution < 5% R404A Viscosity > 20 cSt Standard design w/o seal BCP 16.5 bar (abs.) Solution 11% Viscosity 12 cSt

LP 4.4 bar (abs.)

from oil separator

HP 20.5 bar (abs.) Viscosity 9 cSt (14% R404A) Bitzer Intro_E –

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General Highlights of Bitzer Screw Compressors BITZER HS. Screw Compressors are the result of more than 20 years of experience in research, development, production and application of screw compressors. The latest step in this evolution features:  Wide product range with the least No. of models  Robust & long term proven construction elements  3-step capacity control from smallest to largest model

50% / 75%

 Unique “low pressure bearing chamber”  Suitable for highly efficient Economiser operation  Comprehensive extent of delivery  Advanced protection system  Complete program of accessories (incl. oil separators, oil coolers)  Independent engineering & production “know how” Bitzer Intro_E –

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General Highlights of Bitzer Screw Compressors BITZER HS. Screw Compressors are the result of more than 20 years of experience in research, development, production and application of screw compressors. The latest step in this evolution features:  Wide product range with the least No. of models  Robust & long term proven construction elements  3-step capacity control from smallest to largest model  Unique “low pressure bearing chamber”  Suitable for highly efficient Economiser operation  Comprehensive extent of delivery  Advanced protection system  Complete program of accessories (incl. oil separators, oil coolers)  Independent engineering & production “know how” Bitzer Intro_E –

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Semi-hermetic Screw Compressor Oil Circuit with HS. Series (Option)

Oil separator NO oil Deliver inside compressor

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General Highlights of Bitzer Screw Compressors BITZER HS. Screw Compressors are the result of more than 20 years of experience in research, development, production and application of screw compressors. The latest step in this evolution features:  Wide product range with the least No. of models  Robust & long term proven construction elements  3-step capacity control from smallest to largest model  Unique “low pressure bearing chamber”  Suitable for highly efficient Economiser operation  Comprehensive extent of delivery  Advanced protection system  Complete program of accessories (incl. oil separators, oil coolers)  Independent engineering & production “know how” Bitzer Intro_E –

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Semi-hermetic Screw Compressor Oil Circuit with HS. Series (Option)

Built in Motor Overload protector Oil sol valve Oil flow switch

Oil level control

Oil filter Oil thermostat Bitzer Intro_E –

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Protection & Control Devices for Screw Compressors SE-E1 (INT69VSY-II) (has to be connected as first item in the control/protection circuit)  Motor Protection with Manual Reset 



PTC sensors for monitoring of motor temperature

Discharge Gas Temperature Protection 

Monitoring of Discharge Gas Temp. (PTC Sensor located in the Compressor Discharge Chamber)

 Fail Prove of PTC-Sensor(s) 

Checking of PTC Sensor Cycle (open circuit, broken line)

 Checking Direction of Rotation & Phase Failures  Interrupts control current and locks-out with wrong direction

Reset: Short interruption of supply voltage (L/N) for at least 5 sec. Further Details: See Applications Manual SH-100 / SH-170 / SH-500

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Protection & Control Devices for Screw Compressors

INT389R

New Generation (SE-C1) is planned to introduce early next year Bitzer Intro_E –

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Protection & Control Devices for Screw Compressors INT389R 

Motor Protection with Manual (or Auto-) Reset 



Function - same as INT69VSY-II

Manual reset: Short interruption of supply voltage



Auto-reset by removing link between B1/B2: 5 faults / 24h accepted

Single phasing / Phase asymmetry protection



automatic start repetition after each 30 minutes

Discharge Gas Temperature Protection 

Function - same as INT69VSY

Manual reset: Short interruption of supply voltage



Auto-reset by removing link between B1/B2: 5 faults / 24h accepted Bitzer Intro_E –

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Protection & Control Devices for Screw Compressors INT389R (cont‘d) 

Limitation of switching frequency  The total of operating & off-time is limited to a minimum of 7 minutes Signal lamp “H2”  Shortening of pause time (for service) by linking Z/B1 for approx. 2 sec.  Minimum starting delay: 30 sec after shut-off (independent from running period)

Further Details: See Applications Manual SH-100 / SH-500

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Protection & Control Devices for Screw Compressors S2 B2 F5 P> F6 P< L1 L2 L3 1 2

11

L

Z

INT 389R 14

24

N

B1 12

S3

B2

H2

Alarm Signal „Possibilities“ K1

K3T

H1

0.5 s Bitzer Intro_E –

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Protection & Control Devices for Screw Compressors Discharge Gas Sensors (Oil Temp Sensor)

PTC100 (HS, OS) PTC120 (CSH) PTC140 (Recips) PT1000 (Recips CIC) Bitzer Intro_E –

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Protection & Control Devices for Screw Compressors Oil flow switch

6 l/min (HS/OS53) 10 l/min (HS/OS64/74) Special versions for NH3 Bitzer Intro_E –

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Semi-hermetic Screw Compressor Oil Circuit with HS. Series (Option)

Water cooled oil cooler Bitzer Intro_E –

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Shell & Tube Condensers Sea Water Version TD 15 K 6,6 to 780 kW TD 10 K 4,5 to 524 kW

Standard Version TD 15 K 8 to 913 kW TD 10K 5,3 to 609 kW Bitzer Intro_E –

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Production Process - Brazing of the Tubes

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Structure of Bitzer Tubes

=> High performance because of tube‘s low fouling behaviour Bitzer Intro_E –

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HS/OS Compressor Models – Capacity Ranges

HSK (-10/45)

11 models

R404A

9 models

R404A

9 models

NH3

9 models

HSN (-35/40) OSK (-10/45)

7 models

OSN (-35/40) OSKA (-10/40) OSNA (-35/40)

7 models 0

50

100

150

200

250

300

350

400

450

500

Cooling capacity range [kW] Bitzer Intro_E –

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Bitzer HS & OS Screw Compressors The Ideal Products for Parallel Operation !!  High pressure oil return  Can be horizontal or vertical mount  Can up to 6 compressors or more

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HS/OS – Capacity Ranges ( maximum 6 units in a rack)

Capacity ranges from 1 x HS./OS.53 >> 6 x HS./OS.7471 HSK (-10/45)

R404A

HSN (-35/40) OSK (-10/45)

R404A

OSN (-35/40) OSKA (-10/40)

NH3

OSNA (-35/40) 0

200

400

10,000 MT Cold room

600

800

1000

1200

1400

1600

1800

Cooling capacity range [kW] Bitzer Intro_E –

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Screws vs. Large Recips.

Screw compressor Or Large Reciprocating compressor?

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Screws vs. Large Recips. Advantages of Screws vs Large Recips 1) Higher Specific Capacity -- based on Displacement - higher running speed 2900 RPM vs. 1450 rpm - much smaller and compact in size, lower weight 0.56 M

75 HP motor 2 4 3

1

0.47 M

2..3 mm

6 5 7

7 Bitzer Intro_E –

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Screws vs. Large Recips. Advantages of Screws vs Large Recips 2) Potential for Economiser Operation for better efficiency - very flat performance characteristic with varying CT - higher COP hence save operating cost

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BITZER Screw Compressor Technologies Compression Process SL

SL

ECO

DL

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SL

SCREW Compressor – Compression Process DL

ECO

p

pc

po

peco

Process with Economiser Standard Process

s

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ECO Oil separator Screw compressor

TXV

Liquid subcooler

TXV Bitzer Intro_E –

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Economiser-System with Heat Exchanger 30 50°C

ECO

20

40 30

Pressure [bar]

20 10 10

8

R404A R507A

0

6 5

-10

4 -20

3

-30

2

∆h Standard

-40°C

∆h with ECO

1 0

50

100

150 200 Enthalpy [kJ/kg]

250

300

350 Bitzer Intro_E –

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SCREW Compressor Technology Arrangement of the ECO Suction Line

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HSK 7461 vs Recip with Identical Displacement -Comparison of Refrigeration Capacity 180

Refr. Capacity [kW ]

160 140 120 100 80 HSK 7461 HSK 7461 ECO Recip

60 40 20

3

VG 220 m /h SST -10°C SH 10 K R 22

0 30

40 SCT [°C]

50 Bitzer Intro_E –

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Performance Data of Reciprocating Compressors vs. Screw Compressors − Refrigerant R404A Refrigerating Capacity [kW]

100 80

VG 100 m3/h SCT 40°C SH 20 K

60 40

RECIP 20

+60%

SCREW SCREW+ ECO

10 -10

-20

-30

-40

SST [°C] Bitzer Intro_E –

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Capacity Increase with reduced SCT [%]

Performance Behaviour οf Screw Compressors with Economizer vs. Reciprocating Compressors 200 190 180 170 160 150 140 130 120 110 100

SST - 35 °C SH 20 K R 404A

RECIP SREW +ECO

20

30

40

50

SCT [°C] Bitzer Intro_E –

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Screws vs. Large Recips. Advantages of Screws vs Large Recips 3) Best parallel system – possible for rack system - simple part load 50% / 75% / 100% - Can start unload - Energy saving, low operating cost - Rack has less risk as not depend on one compressor

Note that oil equalizing is very difficult for recips rack!

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Screws vs. Large Recips. Advantages of Screws vs Large Recips 4) Less Noise - Twin screw rotors not touching each other, can even rotate a 75HP screw with hand - less wear and tear, hence longer life time - less vibration – run like a smooth 10 cylinders recips - reduce chance of pipe fracture and system leakage - no need discharge muffler

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Screws vs. Large Recips. Advantages of Screws vs Large Recips 5) Less moving parts - No working valves to fail - more tolerence to liquid slugging - Improve reliability and durability - BITZER screw‘s design life is 15 years!

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Screws vs. Large Recips. Advantages of Screws vs Large Recips 6) Easy Maintenance - Oil cleaness - oil temperature check - bearing check

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Screw Compressors (HS & OS) Service and Maintenance Works 

Oil Filter – & Replacement 

change after first 50...100 h (operating hours) recommended



check all 5.000 h (or yearly respectively) 



must be replaced when pressure drop > 0.5 bar

Oil Change 



with HCFC and HFC refrigerants 

not necessary when using suction line fine filter (10 µm)



mandatory with contaminated systems and with acid formation

with NH3 (unsoluble lubricants) 

first change after 100 h (oil and oil filter)



add oil if requested -- change all 5.000 h (or yearly respectively)

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Screw Compressors (HS & OS) Service and Maintenance Works 

Oil Solenoid Valve 

 



Check diaphragm all 5.000 h (or yearly respectively) 

when deformed: change diaphragm and back-up ring (fitting position !!)



check system and eliminate causes of oil migration into compressor

Replacement after 100.000 h recommended

Oil Flow Switch 

Check all 5.000 h (or yearly respectively)



Replacement after 100.000 h recommended

Discharge Check Valve 

Check all 5.000 h (or yearly respectively)



Replacement after 20.000 .. 40.000 h recommended Bitzer Intro_E –

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Screw Compressors (HS & OS) Service and Maintenance Works 

Shaft Seal 

Leakage tolerable up to 0,05 cm3/h



Check intervalls -- depending on application







AC all 5.000 h



MT & LT all 10.000 h

Replacement after 20.000 .. 40.000 h recommended

Pressure Relief Valve 

Maintenance free  



Opening pressure differential ∆p = 28 bar Tightness check recommended after actuation ( High pressure cut-out)

Replacement after 100.000 h recommended

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Screw Compressor Ball Bearings Inspection and Replacement Intervalls Replacement Intervals for a preventive maintenance see table on next slide 

The total life span potential for normal operation of the bearings is not reached



Due to occasional deviations from normal operating conditions like 

Lack of oil



Less oil viscosity caused by wet operation



Insufficient suction superheat



Thermal Overload

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Screw Compressor Ball Bearings Inspection and Replacement Intervalls Inspection / replacement intervall recommendations -- operating hours (h) Refrigerant

AC application

MT

LT

R134a

1)

10.000 / 50.000 --

10.000 / 50.000

--

R22, R407C

1)

10.000 / 40.000

10.000 / 40.000

10.000 / 50.000

R404A, R507A

1)

10.000 / 40.000

10.000 / 40.000

10.000 / 50.000

R717

1)

10.000 / 40.000

10.000 / 40.000

10.000 / 50.000

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Screws vs. Large Recips. Disadvantages of Screws vs Large Recips Cost!! Usually higher investment cost for small capacity but more economy for larger capacity But BITZER‘s screw is relatively small in sizes hence sometimes it‘s not more expansive than Large Recips compressors

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Lubricants for Screw Compressors – Overview Oil type

Refrigerant

Compressor type

Oil injection temperature

B 100 (Alkyl Benzene)

R22

HS.53/64/74 OS.53/74

max. 80 °C max. 80 °C

B 150 SH (Complex Ester)

R22

HS.53/64/74 OS.53/70/74

max. 100 °C max. 90 °C

R22

CSH, HSKC

inside: max. DGT 120°C

R134a/R404A/R507A

HS.53/64/74 OS.53/74 CSH, HSKC

max. 100 °C max. 90 °C inside: max. DGT 120°C

OS.A 53/74 OS.A 53/70/74 OS.A 53/74

max. 50 °C max. 60 °C max. 60 °C

B 320 SH (Complex Ester) BSE 170 (Polyol Ester)

R134a, R407C Clavus 32/46 (MO) Clavus 68 (MO) SHC 226E (PAO)

NH3

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