
	Machinist's Mate	MM
	Machinist's mates operate and maintain steam turbines and reduction gears used for ship propulsion and auxiliary machinery such as turbogenerators, pumps and oil purifiers. They also maintain auxiliary machinery outside of main machinery spaces, such as electrohydraulic steering engines and elevators, refrigeration plants, air conditioning systems and desalinization plants. They may also operate and maintain compressed gas producing plants.

Machinist's Mate (Surface)

(MM) Machinist's mates operate and maintain steam turbines and reduction gears used for ship propulsion and auxiliary machinery such as turbo generators, pumps and oil purifiers. They also maintain auxiliary machinery outside of main machinery spaces, such as electro hydraulic steering engines and elevators, refrigeration plants, air conditioning systems and desalinization plants. They may also operate and maintain compressed gas producing plants.

What They Do

The duties performed by MMs include:

• aligning piping systems for oil, water, air and steam, and controlling the operation of ship boilers and steam turbines used for ship propulsion and service systems;

• controlling operation of turbo generators used to produce electrical power;

• cleaning, adjusting, testing and performing other preventive maintenance on a ship's boilers, main engines, turbo generators and other auxiliary machinery including steering engines, elevators, winches, pumps and associated valves;

• operating and maintaining desalinization plants (distilling plants) to make fresh water from sea water;

• maintaining refrigeration plants, air conditioning systems and galley equipment;

• repairing or replacing valves, pumps, heat exchangers, compressors, steam turbines and hydraulic or pneumatic control devices;

• making entries in and analyzing machinery operating records and reports.

Credit Recommendations

The American Council on Education recommends that semester- hour credits be awarded in the vocational certificate or lowerdivision bachelor's/associate's degree categories for courses taken in this rating on machinery maintenance, blueprint reading, air conditioning and refrigeration.

Qualifications and Interests

Machinist's mates should have clear speech, physical stamina, manual dexterity and the ability to work with others as a team. They should know how to use common hand and power tools and enjoy working with mechanical devices. Other helpful characteristics are resourcefulness and an interest in learning new ideas and skills. Normal hearing is required.

Working Environment

Machinist's mates work within the hull of a ship in fire rooms, boiler rooms, engine rooms or shops. These locations are sometimes hot and noisy. MMs may be required to perform some heavy physical work. They must be able to work closely with others and, in some cases, with limited supervision.

Opportunities

The Navy has a continuing need for qualified machinist's mates. Approximately 6,300 men and women perform duties in the MM rating aboard conventional steam-propelled ships and at shore stations. Opportunities for placement are good for qualified candidates.

Navy MM - Steam Plant/Auxiliary System Maintainer

Steam Plant Auxiliary Systems Maintainers operate and maintain steam turbines and reduction gears used for ship propulsion and auxiliary machinery such as turbo-generators, pumps and oil purifiers. They also maintain auxiliary machinery outside of main machinery spaces, such as electro-hydraulic steering engines and elevators, refrigeration plants, air conditioning systems and desalinization plants. They may also operate and maintain compressed gas producing plants. The duties performed include: aligning piping systems for oil, water, air and steam, and controlling the operation of ship boilers and steam turbines used for ship propulsion and service systems; controlling operation of turbo-generators used to produce electrical power; cleaning, adjusting, testing and performing other preventive maintenance on a ship's boilers, main engines, turbo-generators and other auxiliary machinery including steering engines, elevators, winches, pumps and associated valves; operating and maintaining desalinization plants (distilling plants) to make fresh water from sea water; maintaining refrigeration plants, air conditioning systems and galley equipment; repairing or replacing valves, pumps, heat exchangers, compressors, steam turbines and hydraulic or pneumatic control devices; making entries in and analyzing machinery operating records and reports. These maintainers work under the supervision of a mentor while learning a trade or skill.

Navy MM - Steam Plant/Auxiliary System Manager

Steam Plant Auxiliary Systems Managers operate and maintain steam turbines and reduction gears used for ship propulsion and auxiliary machinery such as turbo-generators, pumps and oil purifiers. They also maintain auxiliary machinery outside of main machinery spaces, such as electro-hydraulic steering engines and elevators, refrigeration plants, air conditioning systems and desalinization plants. They may also operate and maintain compressed gas producing plants. The duties performed include: aligning piping systems for oil, water, air and steam, and controlling the operation of ship boilers and steam turbines used for ship propulsion and service systems; controlling operation of turbo-generators used to produce electrical power; cleaning, adjusting, testing and performing other preventive maintenance on a ship's boilers, main engines, turbo-generators and other auxiliary machinery including steering engines, elevators, winches, pumps and associated valves; operating and maintaining desalinization plants (distilling plants) to make fresh water from sea water; maintaining refrigeration plants, air conditioning systems and galley equipment; repairing or replacing valves, pumps, heat exchangers, compressors, steam turbines and hydraulic or pneumatic control devices; making entries in and analyzing machinery operating records and reports. These managers have mastered a trade or skill and are qualified to mentor Steam Plant / Auxiliary Systems Technician(s) and Steam Plant / Auxiliary Systems Maintainer(s) and carry on the craft independently.

Navy MM - Steam Plant/Auxiliary System Technician

Steam Plant Auxiliary Systems Technicians operate and maintain steam turbines and reduction gears used for ship propulsion and auxiliary machinery such as turbo-generators, pumps and oil purifiers. They also maintain auxiliary machinery outside of main machinery spaces, such as electro-hydraulic steering engines and elevators, refrigeration plants, air conditioning systems and desalinization plants. They may also operate and maintain compressed gas producing plants. The duties performed by Steam Plant/Auxiliary System Technicians include: aligning piping systems for oil, water, air and steam, and controlling the operation of ship boilers and steam turbines used for ship propulsion and service systems; controlling operation of turbo-generators used to produce electrical power; cleaning, adjusting, testing and performing other preventive maintenance on a ship's boilers, main engines, turbo-generators and other auxiliary machinery including steering engines, elevators, winches, pumps and associated valves; operating and maintaining desalinization plants (distilling plants) to make fresh water from sea water; maintaining refrigeration plants, air conditioning systems and galley equipment; repairing or replacing valves, pumps, heat exchangers, compressors, steam turbines and hydraulic or pneumatic control devices; making entries in and analyzing machinery operating records and reports. This individual would be expected to perform work independently and mentor Steam Plant / Auxiliary Systems Maintainer(s) with very limited supervision.