PART C - FITTINGS AND PIPE REPAIR ACCESSORIES
Fittings. Standard, groove-type fittings include elbows, tees, and reducers such as the following:
Standard Tee Fittings - Standard tee fittings provide a splitting of the fuel stream. These fittings have a
characteristic "T" shape.
Reducing Tee Fittings - Reducing tee fittings allow reduction in one leg of the branch, either through
the tee portion or through the branch portion of the tee.
Elbow Fittings - Provide for the change in the pipeline direction by 90 or 45 degrees.
Reducers - Provide a connection from one diameter of pipe to some smaller diameter of pipe.
Repair clamps. Listed below are some of the more common types of clamps used to repair leaking
pipelines.
Pit Leak Clamps - Pit leak clamps are designed to temporarily repair a leak caused by a small hole such
as a pit.
Split Leak Clamps - Split leak clamps are designed to temporarily repair a leak caused by a split pipe.
This clamp is limited in the size of the split which can be repaired due to its limited length.
Over-Coupling Leak Clamps - Over-coupling leak clamps are designed for placement over the regular
split-ring, groove-type coupling when a leak develops from the initial coupling.
A pipeline leakage report will be completed for all leaks occurring in a pipeline.
PART D - PUMPS
Pipeline pumps consist of one or more impellers mounted on a rapidly rotating shaft. Liquid enters the
impeller at its center and is impelled outward by centrifugal force into the volute of the pump casing. The
volute catches the discharge and converts peripheral velocity into head pressure while conducting the liquid
at a reduced flow rate to the discharge nozzle of the pump casing. Different pumps are used on aluminum
and steel pipeline systems.
6-inch, Single-Stage Pump - The 6-inch, single-stage pump is a self-priming, centrifugal pump
equipped with a mechanical shaft seal. Suction and discharge connections are grooved pipe. Maximum
safe working pressure is 207 PSI or 660 feet of head for fuel with a SG of 0.725.
6-inch, Two-Stage Pump - The 6-inch, two-stage pump is a multi-stage pump fitted for external
connection to operate either in series or in parallel. Maximum safe working pressure is 700 PSI or 2,390
feet of head for a fuel with a SG of 0.725.
800 GPM Mainline Pump - The 800 GPM mainline pump is a new pump used for operation in an
aluminum pipeline system. It is a skid-mounted, three-stage centrifugal pump.
PART E - PIPELINE SCRAPER OPERATIONS
Scrapers are devices inserted into the pipeline to remove internal scale, rust, or other foreign material. In
the petroleum industry, scrapers are often called "pigs" or "go-devils." Two types of scrapers are used:
Steel Brush Scraper - The steel brush scraper is constructed of a tubular shaft on which are mounted
two sets of four spring-loaded steel brushes and two synthetic rubber cups. The spring-loaded steel
brushes clean the walls of the pipe. The front and rear brush groups are staggered to cover the entire
pipe surface. The tubular shaft of the scraper is open at the rear, which permits a fraction of the stream
to flow into the scraper and escape through small ports near the front end, thereby agitating and
propelling the loosened scale forward. This prevents the scale from accumulating ahead of the scraper,
causing the line to become clogged. This type of scraper comes in 6-, 8-, 10-, and 14-inch sizes. The
10- and 14-inch scrapers have three synthetic rubber cups.
Poly Pig Scraper Device - The poly pig scraper device is constructed of foam-type material and
wrapped with abrasives to clean the pipeline. They are able to make 90-degree turns in the pipeline and
are inexpensive, though they do not clean as thoroughly as, steel brush scrapers nor are they as durable.
Military pump station manifolds have two scraper stations; one for launching and another for receiving.
Before launching a scraper, lines should be free from sharp bends and valves that do not open the full
4-4
QM 5096
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