Engineering Training

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ASSIGNMENT SHEET

Assignment Sheet Number 64P7-101

INTRODUCTION

LESSON TOPIC LEARNING OBJECTIVES

TERMINAL OBJECTIVE:

ENABLING OBJECTIVE:

STUDY ASSIGNMENT

1. Read Information Sheet 64P7-101.

2. Outline Information Sheet 64P7-101 using the enabling objectives for lesson 64P7-101 as a guide.

3. Answer the study questions.

STUDY QUESTIONS

1. How many major auxiliary spaces are on an FFG 7 class ship?

2. What equipment is located in the Main Engine Room (MER)?

3. Describe the location of the APUs relative to the Pilot House?

4. Describe the methods of normal GTE control and the console from which it is available?

INFORMATION SHEET

Information Sheet Number 64P7-101

INTRODUCTION

REFERENCES

(a) FFG 7 Propulsion Plant Manual/S9234-BL-010

INFORMATION

1. FFG 7 Program

1. The Navy of the mid-seventies was being designed to consist of a limited number of very expensive, very capable warships (high mix) and many less capable warships (low mix), fully capable of performing certain tasks. This was known as the "High mix - Low mix concept. The FFG 7 class represents the low mix end of the spectrum.
2. Program objectives: The requirement to minimize changes in the class was implemented by a lead ship undergoing testing and evaluation to expose technical issues. This led to the "fly before buy" concept where the lead ship of the class was delivered two years prior to completion of the class. The ship design was required to be produced industry wide rather than depending on a specific construction site and method of construction. Standardization was stressed throughout the class because of the significant benefits to be obtained, particularly in view of the unique design and building concepts.

2. Ship Characteristics: The FFG 7 class can be divided into two distinct groups. Later ships in the class were built with an extended stern and increased displacement as a result of installation of the SQQ-89 system. Some earlier ships of the class were backfitted with this modification, although some did not receive the entire SQQ-89 package resulting in a difference in length and displacement throughout the class. Consult the Ships Information Book for your specific platform to determine which modification applies to you. Listed below is a summary of ships characteristics both with and without the modifications mentioned above.

Without SQQ-89 With SQQ-89

Displacement

full load 3736 tons 3898 tons

limiting 3830 tons 3900 tons


Length between 408 feet 408 feet

perpendiculars


Length overall 445 feet 453 feet


Beam 47 feet 47 feet


Navigational Draft 24 ft 6 in 25 ft 6 in


Accommodation 17 Officers 19 Officers

15 CPOs 15 CPOs

153 Enlisted 185 Enlisted


Fresh Water capacity 8800 gallons 8800 gallons


Fuel oil capacity

F-76 205,000 gallons 205,000 gallons

JP-5 21,000 gallons 21,000 gallons


Main Engines 2 LM2500 Gas Turbine Engines (GTE), 1 shaft, 40,000 Shaft Horse Power (SHP)

NOTE: The accomodations increase is not a result of the addition of the SQQ-89 system. Some ships have made the crew lounges into berthing compartments to support the greater crew requirements. If these modifications have not been made you can expect to have fewer crew members.

3. Ship operational requirements:

1. Speed - Ship trials have shown the ship capable of speeds in excess of 30 knots. Acceleration is from 0 to 30 knots in 43 seconds, and from back full (12 - 15 knots) to ahead flank (30 knots plus) in less than 2 minutes.
2. Endurance - The FFG 7 class is capable of traveling 4500 nm at 20 knots without refueling.

1. Ship engine control modes:

1. Manual control - This control mode requires the operator to separately position the GTE throttles, as well as the appropriate feet of propeller pitch in order to make the ordered ship’s speed.
2. Programmed control - This mode of control takes a single ship’s speed input via an integrated throttle and using a computer processor automatically schedules GTE throttle position and propeller pitch to obtain the ordered speed.

2. Engineering control consoles:

1. Ship Control Console (SCC) - Located in the pilot house. In addition to the multiple systems that can be controlled at the SCC, the center section contains an integrated throttle which allows the bridge to control the speed of the ship. This is the most remote station where ship’s speed is controlled, and is normally the station that has engine control while underway. Only programmed control is available at this console.
2. Propulsion Control Console (PCC) - Heart of the PCS (Propulsion Control System). This console is located in Central Control Station (CCS), the space comparable to Main Control on other platforms. This space is manned by the Engineering Officer of the Watch and Electrical Plant Control Console operator whose function will be described in a later topic. The PCC contains a special purpose digital computer called the processor which monitors and controls various aspects of the propulsion system such as: LM2500 (GTE), GTE lube oil and fuel oil systems, Main Reduction Gear (MRG), Controllable Pitch Propeller (CPP) system, seawater cooling system, and ship speed. Both programmed and manual control are available from this console.
3. Local Operating Panel (LOP) - Located in the Main Engine Room (MER), this console provides local control of GTEs and pitch. Only manual control is available at this console.
4. Electric Plant Control Console (EPCC) - Located in CCS, this console controls the four Ships Service Diesel Generators (SSDGs). It provides automatic monitoring and control of the ship’s electrical plant allowing the console to take corrective actions without operator interface. This console removes the necessity to man all SSDGs and electrical switchboards during normal underway operations.
5. Auxiliary Control Console (ACC) - Located in CCS, primarily a large status board for monitoring auxiliary equipment, but does contain some control features, particularly the ability to remotely secure (emergency stop) some auxiliary equipment. Local watch-stander action is required to restore the equipment to operation. Equipment monitoring includes: Evaporators, High Pressure Air Compressors, Low Pressure Air Compressors, Air Conditioning Units, Chilled Water System, Refrigeration system, Fuel Oil Transfer System (pumps and purifiers), Waste Heat System, Bleed Air System and Collection Holding and Transfer System.
6. Damage Control Console (DCC) - Located in DC Central (forward side of CCS). Divided into two panels.

1. The upper panel is called the Hazard Detection Panel and provides alarms and indications for various DC related systems such as flooding, high temp, Halon, AFFF, CO2, sprinkling systems, and ventilation systems.
2. The bottom panel of the DCC is the Firemain Control Panel and from this panel all fire pumps can be controlled as well as various system isolation valves.

3. Propulsion capability and equipment: (see Figure 1 for equipment layout)
1. Power Train:

1. The main propulsion plant consists of two LM2500 GTEs which act as the ship’s prime mover. The GTEs drive the shaft through a standard type destroyer main reduction gear creating up to 40,000 SHP. The propulsion plant is normally controlled from one of three locations: the SCC, PCC, and LOP. Emergency control of the plant is possible through the Emergency Manual Control Unit (EMCU) which controls a single GTE and the Oil Distribution Box (OD box) which manually controls propeller pitch.

1. The primary fuel which is burned in a GTE is F-76. F-44 which is used to support the ship’s aviation assets also provides an emergency fuel supply for the GTEs. F-76 refueling stations are located on the 02 level, two forward and two aft. Also located aft are the refueling risers for F-44. Refueling can be accomplished at a forward or aft station, or from both at the same time. Fueling is essentially a manual operation with the main transfer manifold located at the forward bulkhead in AMR 1.
2. Everything concerned with the internal transfer of F-76 is located in AMR 2, including the fuel oil heaters, transfer pumps, purifiers, prefilters and coalescers. Control of the F-44 system is located in AMR 3. Here we have JP-5 storage and service tanks; transfer, service, and stripping pumps, and the filter-separators.

2. Main Reduction Gear (MRG) - Located in the MER

1. The MRG is a standard double reduction, double helical, locked train type gear. The accessories mounted on the MRG are the shaft brakes, the attached Controllable Pitch Propeller (CPP) pump and the standard turning gear.
2. The MRG lube oil system provides cooling and lubrication to the MRG via two motor driven pumps. To protect the MRG in event of electrical power loss, the ship is provided with an air driven coastdown pump with sufficient air stored in flasks to allow for a normal shutdown of the main plant.

3. The shaft is mounted at a 7 degree rake which enables the use of a relatively short shaft. The shaft is supported by a single line shaft bearing located in Auxiliary Machinery Room (AMR) 3, a stern tube bearing where the shaft exits the hull, also located in AMR 3, and by a strut bearing.
4. Controllable Pitch Propeller (CPP) - The CPP System has two major pumps which supply hydraulic oil to the propeller, one pump is electric driven and is referred to as the Standby Pump, the second is a gear pump which is driven by the MRG. The hydraulic oil is routed through the Hydraulic Oil Power Module (HOPM), and then the Oil Distribution Box (OD Box) which is located between the GTM modules just forward of the MRG. From the OD Box the oil is ported down the shaft to the propeller hub where it acts to position the propeller blades. The FFG 7 class has a single 5 blade screw 16 ft 6 inches in diameter.

2. The ship is equipped with two retractable 350 Horse Power Auxiliary Propulsion Units (APU) which are designed to propel the ship at approximately 5 knots in a calm sea. These units are routinely used during maneuvering and docking evolutions. These units are raised and lowered using equipment located in the APU Room. Once extended, they are normally controlled from the bridge at the SCC.

4. Electrical capability and equipment:

1. Ship Service Diesel Generator (SSDG) - The ship has four 1000 kilowatt diesel generators. Nr 1 SSDG is in AMR 1, Nr 2 and 3 SSDGs are in AMR 2 and Nr 4 SSDG is in AMR 3. Like the GTEs, the SSDGs have enclosures to provide acoustic protection and also form a boundary in order that the SSDG may be protected by Halon. The SSDGs are normally controlled remotely from the EPCC in CCS, but there is a Local Control Panel (LCP) for controlling the diesel manually. Each diesel has a seawater cooling pump, jacket water cooler, waste heat cooler, waste heat pump, and return fuel oil cooler. The SSDGs only fuel source is from the F-76 system.
2. Switchboards (SWBDs) - Each SSDG has an associated switchboard. Nr 1 SWBD is located in the Switchgear Room which is directly above AMR 1. Nr 2 and 3 SWBDs are in AMR 2. Nr 3 SWBD is unique in that it contains seven shore power breakers. The shore power connection box is located on the 02 level and has the capability of receiving seven cables/400 amps each. Nr 4 SWBD is located in CCS.
3. 400 Hz Static Frequency Changers (SFC) - The ship has three 150 KW 60/400 Hertz SFC, two are located in the AC Machinery Room and one is located in the 400 Hz Room just forward of the starboard helicopter hangar. One SFC is more than sufficient to provide power for all 400 Hz loads.

5. Auxiliaries

1. Air Systems - The ship has two Low Pressure Air Compressors (LPACs) and two High Pressure Air Compressors (HPACs). Both Nr 1 LPAC and HPAC are located in AMR 2. Nr 2 LPAC and HPAC are located in AMR 3. Both sets of compressors support the ships service air system.
2. Potable Water System - Everything associated with fresh (potable) water is located in AMR 3. The ship has two 4000 gallon per day distilling plants interfacing with the firemain and the Waste Heat Systems. These evaporators discharge to a holding tank. From this tank, distilled untreated water can be taken for various equipment services requiring distilled water. The bulk of the distilled water, however, passes through the proportioning brominator where it is treated and placed in one of four storage tanks for crew use.
3. Firemain - The ship has five 1000 GPM fire pumps normally controlled from the DCC. Nr 1 fire pump is located in the Fire Pump Room, Nr 2 and 3 fire pumps are located in AMR 2, and Nr 4 and 5 fire pumps are located in AMR 3.
4. Steering Gear - The steering gear is a simple ram unit with two electric steering gear pumps. The single rudder is offset 18 inches to starboard to give the ship an even turning radius, regardless of direction of turn.
5. Air conditioning plant (A/C) - A/C is supplied by three 80 ton reciprocating units. Nr 1 is located in the A/C Machinery Room while Nr 2 and 3 are in AMR 2.

Figure 1