Section 6 — Rotating Equipment

Oil Mist Lubrication Systems - Construction

IPE Engineering Practice IPE-EP-6-9-4

Document number: IPE-EP-6-9-4 · Section: 6 — Rotating Equipment

SCOPE

• This standard covers the fabrication, erection, inspection, testing, cleaning, and checkout of oil– mist lubrication systems.
• An asterisk (*) indicates a decision by the Owner’s Engineer is required or that additional information is furnished by the Purchaser.
• Any deviation from this Practice must be approved by the procedure described in EP 1–1–3.
• A revision bar indicates all changes made to this Revision.

2.0 REFERENCES

The latest edition of the following standards and publications are referred to herein.

STANDARDS AND PUBLICATIONS

DEFINITIONS

• Contractor - Company or business that agrees to furnish materials or perform specified services at a specified price and/or rate to the Owner.
• Inspector - A Refining Company appointed engineer or inspector.
• Owner - Refining Company.
• Owner’s Engineer - A Refining Company appointed engineer.

GENERAL

• The Owner’s Engineer will be available for consultation and technical assistance.
• Equipment, components, and piping shall be installed as shown on construction drawings.
• (*) Unless otherwise specified, the Owner will furnish the solvent oil, or water-chemical mixture for internal cleaning by flushing, steam for blowing out, and the required lubricating oil to fill the oil reservoir. Where hot equipment is in operation, the Owner may specify a cleaning fluid or solvent oil.

OIL–MIST PIPING FABRICATION

• Cut pipe or tubing ends shall be deburred and reamed where necessary so that there is no reduction of the inside diameter at the cut.
• Piping shall be fabricated so that the use of piping fittings is minimized. Reducing swage nipples and reducing couplings shall be used in lieu of reducing bushings.

• No welded joints are permitted. Threaded joints shall be used except where special Dresser– type couplings may be provided at oil–mist generator.

OIL–MIST PIPING INSTALLATION

• Unless specifically detailed on drawings, all piping shall be routed, detailed, and supported in the field with all joints exposed to view. No underground piping is permitted.
• Each piece of pipe and all fittings shall be swabbed with a clean, lint–free cloth prior to joining any threaded connections. Extreme care shall be taken to keep the interior of all piping, tubing, and equipment clean.
• Only Teflon paste sealant shall be used in making up pipe–threading joints.
• (*) Oil–mist headers and branches shall be sloped, unless otherwise specified, to drain to the mist generator or to the equipment. The amount of slope shall be a minimum of 2 inches per 10 feet for a distance of 40 feet from the generator. Beyond this distance, the slope shall be a minimum of six inches per 100 feet towards the equipment. Greater slopes may be required where ambient temperature may be below 15ºF. Unavoidable low points shall be provided with drains. The type and location of all drains must be approved by the Owner.
• (*) Oil–mist header branch connections for purge mist application shall be made per EP 6–9–3, Figure 1 for those wet sumps specified by the Owner.
• (*) Tubing and piping shall be properly supported. Oil–mist headers and horizontal branches shall not have low pockets. All steel materials used in fabrication of supports shall be galvanized, unless otherwise specified.
• The end of each piping lateral shall be supported near the reclassifier fitting(s). The anchor shall be connected to permanent structures, piping, foundations, or other equipment that are not normally removed for maintenance.
• Tubing shall be installed so that no oil will be trapped. Tube benders shall be used as required so that tubing will be installed without kinks, wrinkles, or flattening.
• Oil–mist fittings and tubing between branches and equipment lubrication ports shall be installed as follows:
• Do not install oil–mist fittings until after cleaning and blowing is completed. Caps, plugs, or block valves shall be installed temporarily to allow cleaning one branch at a time.
• Remove temporary block fittings and install oil–mist fittings.
• (*) Make connections to equipment lubrication ports after blowing is completed and approved by the Owner’s representative.
• The reclassifier fitting shall be connected to the distributor block for all applications.
• Equipment lubrication ports shall remain plugged until connections to lubrication systems are made.

7.0 RETROFIT OF EXISTING PUMPS

If bearing housing closure–type oil seals are used on existing equipment, a permanent vent hole shall be drilled in each bearing housing in a manner that allows the mist to pass through each bearing yet prevents the entrance of rain water. The vent holes shall be 1/8–inch minimum for dry sump installations.

INSPECTION AND TESTING

• (*) The Owner reserves the right to witness all tests and to inspect all work and materials for conformance to specifications and standards. Defects revealed by inspection or testing shall be repaired.
• The Owner’s representative shall be notified of any changes in work schedules in order that the necessary inspection may be made.

SYSTEM INTERNAL CLEANING AND RUN–IN

• (*) Steam above 100 psig shall be used for blowing out the piping distribution system. Blowing shall continue for one hour minimum and until polished surface aluminum targets located at the most distant points show no pitting. Oil mist generator must be isolated during steam blowing. The Owner will provide detailed system cleaning procedures.
• The grease fitting and vent passages of bearings that have been grease lubricated shall be cleaned out before connecting to an oil–mist system.
• After blowing, the oil–mist system shall then be run–in using specified lubricant as follows:
• Fill the oil supply reservoir and oil–mist generator reservoirs with specified lubricant.
• Connect the 120–volt power wires at the terminal strip inside the mist unit.
• The air heater shall not be turned on until air is flowing through the heater.
• Operate the mist system at 10 inches water pressure and clean all plugged mist fittings. For this lubricant flushing operation to be considered complete, the mist system shall operate continuously for a minimum of 48 hours using specified lubrication without plugging any of the mist fittings, and without any pulsating header pressure indicating low–point oil accumulation in piping. After flushing, a check of the system’s oil consumption at design pressure shall be made.
• A record of all key system components and operating parameters shall be furnished to the Owner’s Engineer. These shall include mist head venturi sizes, a complete tabulation of all metering orifice fittings, regulated supply air pressure, and oil mist header pressure with generator(s) set at design conditions.
• (*) ANY modifications to the system must be approved by the Owner’s Engineer.
• The system should be placed in oil–mist service immediately after cleaning.

SYSTEM ADJUSTMENTS

• After the oil–mist system has been run–in with specified lubricant as described in Paragraph 9.3, it shall be connected to equipment lubrication ports.
• Reservoirs of equipment that are to operate with wet sumps shall be hand filled with lubricant to the proper level. Dry sump lubricated bearings must be pre–lubricated with ISO Grade 100 lubricant before starting new machinery for the first time. An alternate method, if time permits, is to have the new bearings on oil mist for 60 minutes minimum prior to start–up.
• All piping and equipment shall be checked for excessive vibration and necessary corrections made.
• Oil mist shall be flowing freely from the oil–bearing reservoir drain or bearing housing outlets on all equipment being served by the oil–mist system. Clean all mist fittings that do not appear to be supplying an adequate flow of oil mist.

• Operational adjustments, in addition to those made to the oil–mist generator, shall be made after all work is complete. They shall be done in the presence of the Owner’s Engineer/Inspector. Adjustments shall be made to the proper levels required by the design of the system. Functions to be checked shall include system mist pressure, oil temperature, air temperature, oil supply pressure, air supply pressure, and all instrumentation and alarms.
• Pressure, temperature, and level shall be adjusted sufficiently to actuate alarms. After testing, reset these pressures, temperatures, and levels to normal operating conditions.

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