COPMPRESSION UNIT FOR HIGH AND LOW PRESSURE SERVICES
A compression unit for supplying high and low pressure services to a plant including a single driver associated with two driver shaft-ends projecting apart from the driver, a first driver shaft end and a second driver shaft end, a first unit being operatively connected to the first driver shaft-end and a second unit being operatively connected to the second driver shaft-end.
1 . A compression unit for supplying high and low pressure services to a plant, the compression unit comprising:
a single driver associated with two driver shaft-ends projecting apart from the driver;
a first driver shaft end and a second driver shaft end; and
a first unit being directly operatively connected to the first driver shaft-end and a second unit being operatively connected to the second driver shaft-end,
wherein the first unit is an overhung impeller, and the second unit is an integrally geared-compressor arrangement comprising a bull gear and a plurality of pinions engaged with the bull gear, wherein the diameter of bull gear is larger than the diameter of pinions.
2 . The compression unit according to claim 1 , wherein the overhung impeller of the first unit is an impeller connected to the first driver shaft-end by a gear arrangement.
3 . The compression unit according to claim 1 , wherein the bull gear is connected by a flanged connection to the second driver shaft-end.
4 . The compression unit according to claim 1 , wherein the integrally geared-compressor arrangement comprises at least one driven shaft.
5 . The compression unit according to claim 4 , wherein at the opposite ends of the at least one driven shaft are provided overhung impellers.
6 . The compression unit according to claim 4 , wherein the bull gear comprises two driven shafts, a first driven shaft and a second driven shaft, each of the first and second driven shaft being provided at its ends with a couple of overhung impellers, respectively first overhung impellers and second overhung impellers.
7 . The compression unit according to claim 1 , wherein the first overhung impellers and the second overhung impellers are fluidly connected thus forming a first multi stage compression unit.
8 . The compression unit according to claim 1 , wherein an outlet of the first unit is fluidly connected to an inlet of the second unit, forming a second multi stage compression unit.
9 . The compression unit according to claim 1 , wherein the inlet of the first unit is fluidly connected to the outlet of the second unit, forming a third multi stage compression unit.
10 . The compression unit according to claim 1 , wherein the driver shaft-ends are the ends of a single driver shaft.
11 . The compression unit according to claim 1 , wherein the two driven shafts are configured to rotate at different rotary speeds.