2205B0JE-DA-J-N_2014.05.
Screw Compressor J-series
Appendix 1.1 Precautions for Design of the Compressor Package
Appendix1-1
Appendix 1
Tips for Design, Manufacturing, and
Installation of the Compressor
Package
The J-series screw compressor is delivered as a package in standard. The appendix describes points
to be considered when designing or manufacturing the package or installing the compressor package.
Appendix 1.1
Precautions for Design of the Compressor
Package
Working Limits of the Compressor
Understand and adhere to the instructions in “2.3 Operation Limits” in this manual chapter 2, so that
the package is designed within the specified operating limits.
The following points are important for the compressor to operate within the operating limits.
Regulate the minimum differential pressure for lubrication within the specifications.
For life time of thrust bearing, sufficient lubrication.
Ensure appropriate flow rate of the lubricant (appropriate pipe diameter) for lubricating and
cooling bearings and seals and discharge gas.
Compressor Protection Function
When placing the compressor into a new or an existing system, always use the specified controller
to control and protect the compressor.
Set the following control values for compressor protection in consideration of the compressor
operating limits.
(1) Protection from abnormal high pressure
(2) Protection from abnormal low suction
pressure
(3) Protection from low supply oil pressure
(4) Protection from high supply oil temperature
(5) Protection from high discharge
temperature
(6) Protection from overcurrent
In addition, install safety valves to pressure vessels such as oil separator, condenser, and
evaporator.
Operating
Control
The specified controller (CP4) for the compressor incorporates the following operational controls
that allow the package to operate smoothly and safely.
1) Start-up preparation control
The following controls are performed before the compressor is started up.
•
The capacity control slide valve of the compressor is checked to see if it is at the minimum
load position.
•
The compressor is lubricated before start-up.
2) Operating control
In normal operation state, the following operational controls are performed.
•
The compressor capacity is controlled according to the load so that the predetermined
temperature or pressure is constant.
•
The compressor stops automatically when the operating conditions reach the set points.
•
Vi is controlled according to the compressor operating conditions.
