Mechanical Engineering Jobs: Petrochemical Plants

This article describes in detail the type of work which a mechanical engineer should expect while working at a petrochemical plant. Be it entry level mechanical engineer or a senior engineer the list of engineering maintenance jobs that are done at a petrochemical facility are:

Petrochemical plants generally have agitators/mixers and other equipment that employ gears. They are used to change the speed of the output shafts depending upon the application. Several types of gears are used.

Maintenance Engineers have to make sure that preventive maintenance plans are followed for these gearboxes. Each gearbox employs specially designated oil recommended by OEM. The selection of oil is based on the variables like maximum speed of gearbox and the temperature.

Another responsibility of maintenance engineer is to send the oil for inspection. Oil is checked mainly for moisture, sulfur content and ferrous levels.

Oil loses its viscosity and lubrication efficiency if moisture increases above the allowable limits. Ferrous levels are monitored to make sure that the gears are running properly and are not grinding each other out. Small backlash of gear is to be blamed for higher levels of iron in the oil.

Oil analysis gives a very clear indication about the problem with gearbox. Maintenance Engineer can decide to increase backlash if he finds increased levels of iron in the oil.

Maintenance Engineer many a times supervise the welding jobs that are carried out within the vicinity of the plant. There are various types of weldings that can be done in one single facility. Of all the different types of weldings, the two basic types are:

1. SMAW or Shielded Metal Arc Welding
2. GTAW or Gas Tungsten Arc Welding

SMAW is also called stick welding and is generally done on carbon steels of thickness greater than 6mm. Structural steels are welded using SMAW.

GTAW is done on thinner metals. It is also used to make high quality welds.

Maintenance engineer has to decide in consultation with Inspection Engineer as to which type of welding and electrodes should be used on a particular application.

Safety at any petrochemical facility comes first. Plants are so dangerous that if maintenance activities are not carried out safely many lives can be lost.

Safety is integral part of any maintenance activity that is carried out within the plant. Whether its simple bearing replacement of pump or mechanical seal replacement of a large agitator, safe work practices are given utmost importance in order to prevent injuries.

For activities that are carried out rarely, job safety analysis is done. Its Maintenance Engineer's responsibility to do the complete analysis. He/she lists down all the steps of the job that is to be carried out. All associated hazards are listed against those steps along with all possible consequences. JSA is to let everybody know what is to be done and what hazards all technicians/engineers will possibly come during the course of the job. It reduces the chances of any mishap.

Maintenance Engineer's job also involves keeping piping systems, structures, platforms and stairs providing access to top of silos, supports rust-free by adhering to strict preventive maintenance schedules. Corrosion and rust makes pipes susceptible to leaks and ruptures while it undermines the structural integrity of structures.

Adhering to PM plans makes pipes to last over the complete life time of plant for which it has been commissioned. PM plans lists down activities that are to be carried out and mention the intervals with which these plans will be implemented.

Plants can be unpredictable at times. Sometimes several equipment breakdown simultaneously. Now work force is always kept lean. So mechanical engineers have to make decisions and prioritize their tasks in order to rectify the problems in the equipment on time. They have to decide the number of persons necessary for doing particular job and how to allocate the workforce for rectifying several problems simultaneously.

Maintenance Engineer has to be on the lookout for the down-times taken by the Operations or any other department.There are several problems that can only be rectified while plant is in shut down. Jobs that were left out for annual shut down can be done in the shut downs that were either caused accidentally or done for some other reasons.

Effectiveness of Maintenance department is reflected by the numbers of PMs (preventive maintenance) and CMs(corrective maintenance). If the ratio of CM/PM is high than this means that either the equipment is being abused by the Operations OR Maintenance is not carrying out preventive maintenance on the schedules that were initially established.