Maintenance: Shift Your Approach to Abandoned Equipment

Almost all plants have provided abandoned equipment in place. This type of equipment can still appear in piping and instrumentation (P & ID) diagrams with a notation such as "OOS" or "AIP" (left in place). The team is left in place for two main reasons: money and uncertainty.

Money. Extraction equipment costs time and money. Changes must often occur during the same change in routine maintenance activities and modifications to the plant. Disconnection and drag the team could extend the duration of a change, which can increase costs even more than the direct cost of removal.

However, many do not realize that leaving the team up is usually not free. You can increase costs by preventing operations and maintenance efforts and future projects. Removing the on-site equipment immediately at the waiting place is almost always cheaper.

Uncertainty. If the computer is still running, often the question of whether it can serve another purpose in the future. For potential savings or ways to avoid additional costs has become so entrenched in the minds of many managers and engineers who are not willing to part with a concern for assets that end up regretting ridding.

However, over the years I found that teams usually left broken in their place due to lack of maintenance and rarely used again.

Therefore, if you are working on a renewal or modification of the plant that will be obsolete equipment, frame the options acting automatically if the team has been eliminated. Include P & ID demolition work in the field as a matter of course, so the removal becomes the default. Make sure that any decision to leave the team has abandoned the place is deliberately and only go after a full safety review.

Following this decision, it is essential:

• Delete all inventory processes. This includes liquids, solids and gases. Unexpected accumulations of solids and liquids in abandoned tanks and exchangers have resulted in numerous security incidents.
• Remove all sludge deposits, scale and corrosion. These often contain residual treatment chemicals and may react unexpectedly.
• Disconnect and empty all hoses.
• Ensure that there is no space available for the water to accumulate and potentially cause an explosion due to frost in cold weather or corrosion failure.
• Limit staff access to confined spaces to avoid inadvertent access.
• Lock the access of animals and birds if necessary.
• Abandoned in an equipment of the operating unit must remain in the P & ID. The P & ID should note that the equipment is out of service and the date it has been taken out of service.

Also, always consider the dangers of abandoned equipment during planned revisions and security risks. These risks may include:

• Obstruction - Difficult access and exit around the team during regular maintenance, emergency evacuation, firefighting and other situations.
• Landslide: Mechanical damage due to corrosion and physical integrity defects.
• Oxygen - the out of service equipment is always exposed to air. Sometimes the equipment voluntarily left open to avoid the formation of steam products. In addition to causing corrosion, oxygen often catalyses reactions. Even chemicals that react very slowly can create problems. The volume of progressive liquid polymerization has opened more than one exchanger. Such incidents can, after the equipment is out of service occur decades.
• Firefighting: Empty computer does not process liquid to evacuate heat. Thus, during a fire, it warms the equipment quickly abandoned. Mechanical failure can occur long before equipment in service. The team collapsed difficult fire fighting and endangering the staff.
• Leaks: abandoned instrumentation ducts can provide routes for liquid and steam are in unexpected places. The underground pipeline can carry materials hundreds of feet from a leak location. This resulted in severe fires.

The best way to manage is to remove the abandoned material. Once you have removed, check the cleaning of the equipment and put some effort into the preparation for storage or get rid of it. If you want to keep your computer, move it to an ossuary plant “boneyard” or spare equipment area.