We have two options for you:
For first option we made a simulation and settle suction pressure with 380 RPM will be around 2.8 barg. In this condition we will have an increase of 2nd stage and 3rd stage temperatures of about 15-20 *C (absolute value will be around 120-127*C) which is fine because we are running lower capacity so cooler will still work properly.
We also checked the reverse pin load and still we have around 170 degree angle (limit is 30 to 50 degree). We want also to highlight that this speed is close to min speed where torsional vibration will appear so pls push SML to increase capacity.
We need to change the inlet PT set point (PALL and PSLL) to 2.5 and 2.3 barg respectively, set the inverter control system to “manual” and with fixed speed of 380 RPM (if you don’t change to manual compressor will increase immediately speed to 980 RPM because initially on delivery there is low pressure (we have to talk about this issue, we think we should implement a double PID system to bypass the problem of low capacity from SML).
Second option, which we prefer and suggest for various reasons (i.e. compressor efficiency, lower temperatures, less load, etc), is to remove HE (head effect) suction valves on 1st stage cylinders, this will allow the unit to run at 4-5 barg at 500 RPM processing 580 Sm3/h, basically the unit will compress only on the bottom side of the 1st stage cylinders. This operation involves compressor valves cover opening and valve internal part removal, it will take 1h to do this operation but I need to be there to supervise it and I need some mechanical technician, relevant wrenches and torque wrench to help me. After SML will increase the flow you can mount back the valve, it is very simple operation.
Kindly wait to startup the compressor up to 5 pm on the 15th so that I can be there and supervise all the activity, we don’t want problem to came up.
Best regards and see you tomorrow
PS kindly use my Get email and not my personal email otherwise I risk to miss some communication