Damaged components should always be replaced with original parts. Adjustment of the safety valves shall only be carried out by authorised personnel

The compressor must not be used if the safety equipment is defective.

The compressor’s automatic control system includes a pressure switch which stops the compressor if the pressure of the lubricating oil falls below a specified minimum level.

INSTALLATION AND OPERATION

Installation instructions

All deliveries of compressor installations are accompanied by documentation of the installation’s dimensions and mounting points. The documentation will also include installation instructions, showing the recommended assembly of equipment and pipe connections.

To achieve problem-free operation, it is important that the base-plate is sufficiently rigid and free from vibrations caused by other machinery. The base of the compressor must lie flat on the base-plate. After installation of the compressor, the alignment between the compressor and its drive motor should be checked.

The compressor installation should be located where the ambient air is as cold as possible. Warm intake air reduces the capacity of the compressor and increases the risk of coking. The ambient temperature for the electrical components must not normally exceed 45°C. The base of the compressor must lie flat on the baseplate.

After tightening the fixings, the alignment between the compressor and motor must be checked as described in Section 5.6. (Even if the installation is mounted on vibration dampers, it is recommended that the alignment is checked after installation.)

The cooling water pipes must be installed in such a way the air pockets cannot occur.

The compressor installation should not be closely surrounded by other equipment which would hinder maintenance work.

Cooling water system

A reliable and adequate cooling water supply is important for the functioning and life-expectancy of the compressor. The necessary cooling water capacities are specified in Table 6.1, and apply both to seawater and freshwater cooling.

Whether the compressor is connected to a central cooling system or is equipped with a separate cooling water pump, it is important to ensure that cooling water circulation is maintained, and the indication of cooling water pressure by the manometer alone is not sufficient proof of this. It is recommended that the cooling water circulation be shut off when the compressor is not running, to avoid the precipitation of condensation in the crankcase.

Too low temperature of the cooling water entering the compressor may lead to an increase in internal condensation formation, and if this occurs, the temperature of the cooling water should be increased. If it is not possible to increase the temperature, for example by recirculation, condensation formation may be reduced by reducing the amount of cooling water within the limiting values specified in Table 6.2.

A thermometer is mounted in the cooling mantle on the cylinder head to monitor the cooling water temperature.

Start-up

In connection with the first start-up or after prolonged downtime, the following procedure should be used:

ACheck oil level.

BCheck that the oil does not contain water or other substances which will impair its quality.

CCheck the compressor valves and apply oil to the cylinders.

DTurn over the compressor by hand, removing the suction valve load by means of the manual unloader. (Set

the lever in the vertical position.)

ECheck the cooling water circulation.

FCheck that the non-return valve between the compressor and the air reservoir is open.

GSet the manual drain valves in the open position.

HStart the compressor.

IIf everything functions correctly, the drain valves and the unloader should be set to the operating positions. (Set the unloader lever in the horizontal position.)

The compressor should be allowed to run for a few minutes before subjecting it to maximum working pressure.

Operation

Under normal operation the pressure and temperatures should be as specified in Table 6.2. Minor deviations may exist for some of the values which are directly influenced by conditions at the working location.

The operation of the compressor is normally monitored by the starter installation’s automated system, which provides, for example, pressure switch monitoring of the lubricating oil pressure and thermostatic monitoring of the cooling water temperature and air temperature. However, it is recommended that the operation and automatic functions of the compressor be inspected regularly.

Under any operating conditions, condensation will precipitate from the compressed air in the HP cooler of the compressor. A water separator is integrated in the HP exhaust manifold to remove this condensation, which is drained through a solenoid valve each time the compressor is stopped. In areas of high atmospheric humidity it is recommended that the solenoid valve also be opened periodically during operation (for example two seconds of draining every ten minutes). It is not necessary to install a water separator in the pipe system between the compressor and the air tank in addition to the compressor’s integrated separator.

In areas of high atmospheric humidity, precipitation of condensed water may also occur in the LP cooler. It is important to prevent this condensation from accompanying the air flow into the high pressure cylinder, where some of the water may penetrate into the crankcase and contaminate the lubricating oil. The compressor is therefore fitted with a water separator after the low pressure cooler which effectively removes condensed water and prevents water droplets from accompanying the air flow into the HP cylinder. The water is drained automatically by a float chamber.

Stopping

To stop the compressor manually for short periods, the following procedure should be used:

AFlip the compressor’s manual unloader to the vertical position to unload the LP suction valve.

BOpen the drain valves.

CStop the compressor.

When stopping the compressor before prolonged downtime, use the following procedure:

ADrain old oil, clean the crankcase sump and fill with new oil.

BApply a suitable corrosion inhibiting oil to the compressor valves, non-return valves, cylinder walls and

open surfaces of the crankshaft.

CIf there is a danger of frost, drain the cooling water.

DSet the manual unloader in the horizontal position so that there is no load on the compressor’s suction

valve.

ETurn over the compressor by hand once a week.

FThe starter panel and other electrical equipment must be similarly protected against corrosion damage.

OPERATIONAL FAILURES

Some of the faults which may occur during operation are summarised below:

	Fault symptom Possible cause Remedy	Fault symptom Possible cause Remedy	Fault symptom Possible cause Remedy
A	The compressor has poor capacity and/or does not produce full pressure.	Dirty, worn or damaged valves.	Inspect and clean all valves. Replace defective parts.
Piston rings have stuck in the ring grooves, or are damaged/broken.	Disassemble the rings. Clean grooves and rings and replace defective parts. Reassemble, applying oil to the cylinder walls.
Leaking safety valve.	Replace safety valve.
Defective cylinder head gasket.	Replace gaskets.
Clogged air filter.	Clean filter.
B	LP safety valve blows.	HP suction valve damaged or dirty.	Inspect and clean valves and replace defective parts.
Leaking seal in HP suction valve.	Replace seal.
LP safety valve defective or damaged.	Replace safety valve.
C	HP safety valve blows.	Stop valve in the air line is closed.	Open the stop valve.
Clogged non-return valve.	Remove and clean non-return valve. Replace defective parts.
HP safety valve defective or damage	Replace safety valve.
D	Valves need overhauling too often.	Overheating.	Check cooling water circulation and temperature. Inspect and if necessary clean coolers.
Polluted intake air.	Inspect intake filter
Poor lubricating oil.	Change oil grade.
Valve clamp bolts not tightened enough.	Tighten the clamp bolts to the correct moment.
E	Overheating and/or abnormal noise in crankcase.	Defective bearings.	Inspect bearings and check clearances.
Low oil level or condensation in oil.	Drain and clean crankcase sump, fill with new oil.
Jamming crankshaft bearing.	Check bearing clearances. Replace defective parts.
F	Piston overheating and friction.	Incorrect fitting of piston or crosshead bearing.	Replace defective parts, check piston clearances, ring clearances and crosshead bearing.
Cooling malfunction.	Check cooling water circulation and temperature.
G	Increased oil consumption	Worn piston rings.	Replace piston rings.
Leakage.	Check the exterior of the compressor.
	H	Oil emission from crankcase ventilation.	Defective or worn piston rings.	Remove and check piston and if necessary replace defective piston rings.
	Defective ventilating valve.	Replace valve.
	I	Ruptured bursting disc.	Cooling water pressure too high.	Check that pressure is within the specified limits.
	Cooling water temperature too high.	Check that temperature is within the specified limits.
	Pressure pulses in cooling water system.	Determine what is causing pulses and eliminate.
	J	Worn rubber lamina in the coupling between compressor and motor.	Poor alignment of compressor and motor shafts.	Correct alignment of coupling.