45 Heales Road, Lara VIC, Australia 3212 Phone +61 3 5275 6644 Facsimile +61 3 5275 3333

Oil Cooler Maintenance (General)

Oil Coolers are designed to give maximum life with minimum maintenance, thus providing efficient reliable service to the end operators. There are environmental conditions however, which reduce the efficiency of the oil cooler both internally and externally, thus reducing the performance. The following information gives a brief description of the various procedures and methods involved in internal and external cleaning. CLEANING & TESTING

A) External Cleaning of Oil Cooler It is essential that the air passages through the oil cooler core be kept reasonably free from obstruction. Excessively fouled oil cooler cores could cause a significant drop in cooling air quantity, with a resultant increase in oil temperatures. Regular inspection will determine the regularity of external cleaning necessary.

Cleaning Methods: 1. When dust accumulation is not severe,

brushing down of the approach air side of the core faces in recommended. A soft type of brush is recommended so as not to damage or deform the core fins. If necessary, this could be followed by blowing compressed air at no greater than 700 kPa through the air side of the oil cooler panels in the opposite direction to the normal air flow until loose material is blown free.

2. If the fin and tube exterior surfaces

become caked with dirt, through neglect, washing and hosing down with detergent and hot water may clean stubborn areas. Shell Teepol or Turco Sokleen (diluted in water) are suitable for this purpose, or

one of many other equivalent detergents. A low pressure (175 kPa) steam jet is also effective in removal of external stubborn dirt.

B) Internal Cleaning of Oil Cooler

If quality oil is used, within the temperature range specified by the oil and equipment manufacturers, little or no internal cleaning should be necessary. However, if due to neglect or equipment failure, scale or foreign material has entered the inside of the oil cooler core it generally follows that the whole system will need cleaning internally. Cleaning Method:

Remove system from oil cooler panel and drain remaining oil. Connect a pump/filter system to reverse flush the oil cooler panel with a flow rate up to 11.36 l/s (150 GPM) filtered to 10 microns. Procedure:

1. Flush the unit with approved cleaning agent filtered to 10 microns.

2. Forward and reverse flush. 3. Purge excess cleaning agent. 4. Oil fog all interior surfaces. 5. Seal unit for storage, shipment or re-

install oil cooler panel.

Air Radiators TECHNICAL INFORMATION BULLETIN No. 50 31st May, 2001 Page 1 of 2

Oil Cooler Maintenance

It is strongly recommended that unless suitable cleaning equipment is available, the oil cooler is sent to a recognised oil cooler repair company, suitably equipped to handle industrial oil cooler equipment. FAILURES

Throughout the design and production phases, oil coolers are subjected to rigorous testing procedures. Therefore, failures are investigated with great interest to identify the cause. Most failures can be attributed to:

1. Poor or incorrect installation, and/or mounting.

2. Operating unit above pressure rating of oil cooler.

3. High and sudden pressure spikes. 4. Using incorrect oil.

5. Operating outside oil and equipment manufacturer's specification.

6. Poor maintenance of oil cooler. 7. Operating environment. SUMMARY

Oil coolers correctly installed, mounted and maintained will offer long life without major cost to the operator. Oil coolers by themselves will not fail - most failures are the result of lack of maintenance of the system, causing erosion and corrosion of the oil cooler panel. Therefore, regular checks are essential to minimise both the cost of repair and down time.

For further information, contact Air Radiators. Ph: +61 3 5275 6644 Fax: +61 3 5275 3333 Email: mail@airrads.com.au

Issue: 1 Date: 31/05/01 ECN: Approval:

Uncontrolled Document - This copy will not be automatically updated.

Air Radiators TECHNICAL INFORMATION BULLETIN No. 49 31st May, 2001 Page 2 of 2