WORK ITEM 1 270 Hot Flush.doc

WORK ITEM 1: Main Diesel Engine (MDE), Perform Hot Flush

1. SCOPE

1.1 Intent. This work item describes the requirements for the Contractor to perform a staged hot flush of the No. 1 Main Diesel Engine (MDE) lubrication oil passages onboard CGC MOHAWK. The engine is an ALCO 251-F series diesel engine.

1.2 Government-furnished property.

None.

2. REFERENCES

Coast Guard Drawings

Coast Guard Drawing 905 WMEC 262-1, Lube Oil System Diag

Coast Guard Drawing 905 WMEC 262-2, Lube Oil Service System »

Coast Guard Publications

None Other References

MIL-PRF-2104H, July 2004, Rev-H, Lubricating Oil, Internal Combustion Engine, Combat/Tactical Service

3. REQUIREMENTS

3.1 General. The Contractor shall adhere to the following general requirements throughout the duration of all flushing stages:

3.1.1 CIR.

None.

3.1.2 Tech Rep.

Not applicable.

3.1.3 Protective measures - general. The Contractor shall furnish and install all protective coverings to seal off and protect all non-affected vessel's components, equipment, and spaces in the vicinity of the work area against contamination during the performance of work. Upon completion of work, the Contractor shall remove all installed protective measures, inspect for the presence of contamination, and return all contaminated equipment, components, and spaces to original condition of cleanliness.

3.1.4 Interferences. The Contractor shall handle all interferences in accordance with SFLC Std Spec 0000, paragraph 3.3.5 (Interferences). Known interferences include, but are not limited to the below-listed:

· Deck plates.

· Piping

· Miscellaneous machinery.

· Wiring and cables/cableways.

3.1.5 Flushing media. The Contractor shall use a MIL-L-2104H Grade MS-HDO 10W flushing fluid (approximately 800 gallons) conforming to MIL-PRF-2104H.

NOTE

Upon completion of lube oil flushing, the flushing oil may be returned to clean containers and can be used for the next hot lube oil flush provided cleanliness of lube oil can be maintained.

3.1.6 Flushing pump. The Contractor shall use a positive displacement pump capable of 260 gallons per minute at 120 PSI.

NOTE

The Contractor should be aware that neither the cutter, nor the cutter support base, is capable of providing the 440 VAC power necessary to operate such pumping systems and that the contractor must provide a suitable 450 VAC power source

3.1.7 Jumper lines. For all lube oil relief and bypass valves, the Contractor shall install jumper lines to facilitate flushing of these valves and associated lines.

3.1.8 Filter/filtration system. The Contractor shall accomplish the following for the flushing media filters/filtration system:

3.1.8.1 Filter the flushing fluid using milspec muslin bags or filters rated at 25 microns.

3.1.8.2 Renew the muslin bags prior to the start of each flushing stage.

3.1.8.3 Renew muslin bags a minimum of every 2 hours to maintain a differential pressure increase of no more than 5 psig over the differential pressure of a clean muslin bag.

3.1.9 Component removal/reinstallation tracking. The Contractor shall ensure that all components removed from the engine/lube oil system are match-marked and tracked via a recorded log to ensure proper reinstallation. Submit a CFR at the end of each flushing stage.

3.1.10 COR notification. Notify the COR at least 24 hours prior to beginning each flushing operation.

3.1.11 Pre-flush cleanliness verification. Prior to starting the staged hot flush, the Contractor shall verify the following and submit a CFR:

3.1.11.1 Engine filters removed and disposed of;

3.1.11.2 Engine sump and screens, filter housing(s), strainer housing(s) have been drained and cleaned;

3.1.11.3 Oil strainers are removed and cleaned;

3.1.11.4 Engine interior surfaces and components (e.g., crankcase, crankshaft, connecting rods, bearing caps, gears, etc.) have been wiped clean and oil-wetted.

3.1.12 Post-flush report requirements. After each flushing stage, submit a detailed report to the COR within 24 hours, to include the following at a minimum:

· Method used to obtain the particulate contamination reading.

· Method used to determine particle size.

· Final contamination level readings.

3.1.13 Flushing waste disposal. All fluids, materials and other waste resulting from the hot flush shall be disposed of in accordance with all applicable Federal, state and local regulations.

3.2 Flushing particulars. Using Coast Guard drawings «APPDOCS2» as guidance, the Contractor shall conduct a 4-staged flush of the engine lube oil system as described herein:

3.2.1 Flushing sequence. Conduct the following MDE hot oil flushes in the following sequence:

· External piping (including prelube);

· Internal piping;

· Combined internal and external piping (excluding prelube);

· In-place lube oil cooler.

3.2.2 Pre-flushing preparations. Ensure that the following preparations are completed prior to commencing the applicable flushing stage procedure:

· Blank off pedestal bearing oil feed lines.

· Blank off turbocharger or blower lube oil feed lines.

· Disconnect the lube oil cooler and install jumper line with valve to by-pass the cooler.

· Disconnect main bearing jumper lines and end plugs on main internal lube oil header; hand clean accessible ports and plug.

· Disconnect all lube oil supply lines to internal components including cam bearing, gear train, governor, and cylinder heads, as applicable.

3.2.3 External lube oil system piping flush.

3.2.3.1 Heat a quantity of clean MIL-L-2104H flushing oil, equaling 60 to 70 percent of sump capacity, to a temperature of 172° to 180° F.

3.2.3.2 Circulate the oil throughout the external lube oil circuit (excluding the prelube system at this time) in the following increments, confirming secure connections prior to each next incremental increase:

· 20 gpm;

· 125 gpm;

· 200 gpm and 120 psi.

CAUTION!

Ensure the external lube oil system valves are aligned properly to allow flushing. Do not open the dirty oil and oil replenishment lines to flushing!

NOTE

The flushing process duration begins when the oil is within and maintains the specified flushing temperature (172° to 180° F), flowrate (200 gpm) and pressure (120 psi).

3.2.3.3 Flush the external lube oil system (excluding the prelube system) for 12 hours.

3.2.3.4 At the end of the 12th hour, open the prelube system to the external lube oil system and flush for at least an additional two hours, at flushing process conditions, until a differential pressure increase of less than 5 psig higher than the differential of a clean muslin bag can be maintained for a 2-hour period.

3.2.3.5 Following the additional two hours (14 hours total), collect all solid-based contaminants (see 4.2) from the muslin bags and determine the total volume of all contaminants. Submit a CFR.

NOTE

The total volume of the solid-based particles shall not exceed the volume of a U.S. quarter (25-cent piece) or contain particles greater than 1/64 inch diameter.

3.2.3.6 If the total particle volume exceeds the volume of a U.S. quarter or any particle exists greater than 1/64 inch diameter, restart the flush. Conduct an ensuing inspection of solid-based contaminants at the end of the additional flush. Submit a CFR.

NOTE

The flushing process duration begins when the oil is within and maintains the specified flushing temperature (172° to 180° F), flowrate (200 gpm) and pressure (120 psi).

The total volume of the solid-based particles shall not exceed the volume of a U.S. quarter (25-cent piece) or contain any particle greater than 1/64 inch diameter.

3.2.3.7 Secure the external lube oil system flushing operation, and all valves to prevent gravity flow back to the engine sump.

3.2.4 Internal lube oil system flush.

3.2.4.1 Heat a quantity of clean MIL-L-2104H flushing oil, equaling 60 to 70 percent of sump capacity, to a temperature of 172° to 180° F.

3.2.4.2 Circulate the oil throughout the internal lube oil circuit in the following increments, confirming secure connections prior to each next increment increase:

· 20 gpm;

· 125 gpm;

· 200 gpm and 120 psi.

CAUTION!

Ensure the internal lube oil system is aligned properly to allow flushing.

NOTE

The flushing process duration begins when the oil is within and maintains the specified flushing temperature (172° to 180° F), flowrate (200 gpm) and pressure (120 psi).

3.2.4.3 Flush the internal lube oil system for 2 hours, at flushing process conditions, until a differential pressure increase of less than 5 psig higher than the differential of a clean muslin bag can be maintained for a 2-hour period. Rotate the engine crankshaft through 90 degrees travel at 20 minute intervals.

NOTE

Ensure lube oil is reaching all internal oil passages by doing a visual inspection; e.g., rocker arms, camshafts, gear trains and piston skirt return passages.

3.2.4.4 At the end of the two hours, collect all solid-based contaminants (see 4.2) from the muslin bags and determine the total volume of all contaminants. Submit a CFR.

NOTE

The total volume of the solid-based particles shall not exceed the volume of a U.S. quarter (25-cent piece) or contain any particle greater than 1/64-inch diameter.

3.2.4.5 If the total particle volume exceeds the volume of a U.S. quarter or any particle be greater than 1/64-inch in diameter, restart the flush until a differential pressure increase of less than 5 psig higher than the differential of a clean muslin bag can be maintained for a 2-hour period. Conduct an ensuing inspection of solid-based contaminants at the end of the additional flush. Submit a CFR.

NOTE

The flushing process duration begins when the oil is within and maintains the specified flushing temperature (172° to 180° F), flowrate (200 gpm) and pressure (120 psi).

The total volume of the solid-based particles shall not exceed the volume of a U.S. quarter (25-cent piece) or contain any particle greater than 1/64-inch diameter.

3.2.4.6 Secure the internal lube oil system flushing operation, and all valves to prevent gravity flow back to the engine sump.

3.2.4.7 Replace the main bearing jumper lines and replace end plugs on main internal lube oil header.

3.2.4.8 Reinstall all lube oil supply lines to internal components including cam bearing, gear train, governor, and cylinder heads.

3.2.5 Combined external and internal flush.

3.2.5.1 Heat a quantity of clean MIL-L-2104H flushing oil, equaling 60 to 70 percent of sump capacity, to a temperature of 172° to 180° F.

3.2.5.2 Circulate the oil throughout the internal and external lube oil circuit (excluding the prelube system) in the following increments, confirming secure connections prior to each next increment increase:

· 20 gpm;

· 125 gpm;

· 200 gpm and 120 psi.

CAUTION!

Ensure the internal and external lube oil systems are aligned properly to allow flushing. Do not open the dirty oil and renewal oil lines to flushing!

NOTE

The flushing process duration begins when the oil is within and maintains the specified flushing temperature (172° to 180° F), flowrate (200 gpm) and pressure (120 psi).

3.2.5.3 Flush the internal and external lube oil systems for 12 hours, at flushing process conditions, until a differential pressure increase of less than 5 psig higher than the differential of a clean muslin bag can be maintained for a 2-hour period. Rotate the engine crankshaft through 90 degrees travel at 20 minute intervals.

3.2.5.4 At the end of the initial 12 hours, collect all solid-based contaminants (see 4.2) from the muslin bags and determine the total volume of all contaminants. Submit a CFR.

NOTE

The total volume of the solid-based particles shall not exceed the volume of a U.S. dime (10-cent piece) or contain any particle greater than 1/64-inch diameter.

3.2.5.5 If the total particle volume exceeds the volume of a U.S. dime or any particle greater than 1/64-inch diameter, renew the muslin bags and continue the flush (without crankshaft rotation) until a differential pressure increase of less than 5 psig higher than the differential of a clean muslin bag can be maintained for a 2-hour period. Conduct an ensuing inspection of solid-based contaminants at the end of the additional flush. Submit a CFR.

NOTE

The total volume of the solid-based particles shall not exceed the volume of a U.S. dime (10-cent piece) or contain any particle greater than 1/64-inch diameter.

3.2.5.6 Secure the internal and external lube oil systems flushing operation, and all valves to prevent gravity flow back to the engine sump.

3.2.5.7 Post-internal and external flush restoration. Upon completion of engine flushing, accomplish the following:

3.2.5.7.1 Drain flushing oil from sump, piping, filter and strainer housings, place flushing oil in clean containers.

NOTE

Every effort shall be made to remove MIL-L-2104H from the lube oil system, to including removal of oil sump screens and wiping the sump clean with lint free rags. This will ensure a satisfactory test for viscosity, which will eliminate the need to change oil after a few hours of engine operation.

Careful use of clean low pressure air (100 psi or less) may be used to blow flushing lube oil back to the engine sump through the filter and strainer housings.

3.2.5.7.2 Clean and inspect lube oil sump using lint-free rags. Clean and inspect internal lube oil pump suction piping from the suction bell mouth or strainer to the pump inlet.

3.2.5.7.3 Restore lube oil system to original configuration in preparation for engine run.

3.2.5.7.4 Clean lube oil filter housing and install 12 new Contractor-provided lube oil filters, PN Alco A910113.

3.2.5.7.5 Clean and inspect system lube oil strainer and housing; install system strainer baskets; install muslin bags in system strainer baskets if configuration permits.

CAUTION!

Thorough inspection of the engine through the air boxes and engine blowers (where applicable) is necessary to avoid the damage of hydraulic lock.

Ensure all temporary modifications to lube oil piping, resulting from flush operation have been reconfigured to the original installation. Ensure lockwire on all main bearing jumper lines and lube oil gallery end plugs have been reinstalled.

Ensure blank flanges to turbocharger(s)/blowers and main bearings (if installed) are removed.

Ensure strainer and filter bypass valves are properly set.

3.2.5.7.6 Refill MDE with new contractor provided lube oil with MIL-L-9000H, 9250 lube oil.

NOTE

Contractor should be aware that approx 330 gallons of oil will be needed and that a viscosity reading must be completed by the COR prior to filling the lube oil system.

3.2.6 Lube oil cooler flushing. The following steps for flushing the lube oil cooler shall be done to accomplish three flushes total: twice in the normal direction of flow, and once in the opposite direction to occur between the two normal-direction flushes.

3.2.6.1 Drain the contents of the lube oil cooler into a suitable container and dispose of in accordance with all local, state and Federal laws and regulations.

3.2.6.2 Ensure lube oil cooler drain valves are shut.

3.2.6.3 Ensure a suitable air vent is installed and properly plugged.

3.2.6.4 Disconnect the lube oil inlet and outlet piping, clean and install blanks.

3.2.6.5 Connect the flushing module to the lube oil cooler to facilitate flow in the same direction as normal flow.

3.2.6.6 Heat a quantity of clean MIL-L-2104H flushing oil, equaling 60 to 70 percent of sump capacity, to a temperature of 172° to 180° F.

3.2.6.7 Circulate the oil throughout the lube oil cooler in the following increments, confirming secure connections prior to each next increment increase, and periodically bleed the air from the lube oil cooler to ensure all air is removed:

· 20 gpm.

· 125 gpm.

· 200 gpm and 120 psi.

CAUTION!

Ensure the lube oil cooler system is aligned properly to allow flushing.

NOTE

The flushing process duration begins when the oil is within and maintains the specified flushing temperature (172° to 180° F), flowrate (200 gpm) and pressure (120 psi).

3.2.6.8 Flush the lube oil cooler for 4 hours in the direction of normal flow.

NOTE

Lightly strike the lube oil cooler and end bells with a rubber mallet periodically to dislodge any trapped contaminants.

Every 30 minutes, open the vent/drain valves (as applicable) to ensure removal of contaminates; drain into a suitable container.

3.2.6.9 Repeat 3.2.6.6 through 3.2.6.8 one time except with flow in the direction opposite of normal flow for only two hours.

3.2.6.10 Repeat 3.2.6.6 through 3.2.6.8 one final time with flow in the direction of normal flow for only two hours.

3.2.6.11 At the end of final flush (third), collect all solid-based contaminants (see 4.2) from the muslin bags and determine the total volume of all contaminants. Submit a CFR.

NOTE

The total volume of the solid-based particles shall not exceed the volume of a U.S. dime (10-cent piece) or contain any particle greater than 1/64-inch diameter.

3.2.6.12 If the total particle volume exceeds the volume of a U.S. dime or any particle is greater than 1/64-inch diameter, renew the muslin bags and continue the flushing sequence until a differential pressure increase of less than 5 psig higher than the differential of a clean muslin bag can be maintained for a 2-hour period. Conduct an ensuing inspection of solid-based contaminants at the end of the additional flush. Submit a CFR.

NOTE

The total volume of the solid-based particles shall not exceed the volume of a U.S. dime (10-cent piece) or contain any particle greater than 1/64-inch diameter.

3.2.6.13 Lube oil cooler restoration.

3.2.6.13.1 Drain all flushing oil from the lube oil cooler into a suitable container.

3.2.6.13.2 Restore the lube oil cooler and all associated piping/lines to original cooler configuration.

3.3 Engine run after flushing completion. In the presence of the Coast Guard Inspector, the Contractor shall thoroughly test and prove the MDE to be in satisfactory operating condition (see 4.1 (Equipment operation)).

CAUTION!

Prior to running the engine, ensure all lines disturbed throughout the flushing process are reattached correctly and are secure. Also verify the engine oil quantity is adequate prior to pre-lubing and starting the engine.

Monitor the differential pressure across the lube oil strainers and filters during engine operation. Ensure the differential pressure does not exceed bypass valves set point. If the strainer or filter requires repeated cleaning to maintain proper differential pressure, the entire flushing procedure shall be repeated.

3.3.1 After 15 minutes of no-load operation, sample and test lube oil for viscosity.

3.3.2 At the discretion of the Engineer Officer and/or COR, continue to run engine at no load and increase engine speed from idle to full speed over a 15 minute period and in accordance with the ships Engineering Operating Procedures.

CAUTION!

Monitor the differential pressure across the strainer and filter during engine operation. Ensure the differential pressure does not exceed bypass valves set point. If the strainer or filter requires repeated cleaning to maintain proper differential pressure, the entire flushing procedure shall be repeated.

3.3.3 Continue to run the engine at no-load full speed for an additional 15 minutes.

3.3.4 Stop the engine and check the lube oil strainer.

CAUTION!

If the strainer contains solid contaminants larger than 1/64 inch or volume of solid contaminants is larger than a dime, repeat the final flush procedures until an acceptable criteria is obtained.

3.4 Inspector witnessing and approval. The Contractor shall ensure that the Coast Guard Inspector is present during all flushing oil sampling and inspection. The Contractor’s final sampling and inspection shall be approved in writing by the COR and Coast Guard Inspector.

4. NOTES

4.1 Equipment operation. Coast Guard personnel will operate all shipboard machinery and equipment during all operational tests.

4.2 Solid-based contaminants. Solid-based contaminants are defined as particles which cannot be crushed between the thumbnail and finger.