[转帖] 砂泵

NEW CENTRIFUGAL PUMPS FOR THE OIL
REFINING AND PETROCHEMICAL
INDUSTRIES
V V Burenin

We consider the design of centrifugal pumps: integrated, for dirty fluids containing solid impurities;
multistage, with the axial force relieved by a device in the form of a drum; self-priming, with a multisectional
casing of annular elements; hermetic integrated, with a stamped outer jacket
Centrifugal pumps are used widely to pump oil and petroleum products, liquefied gases, acids, alkalis, and fluids
that pose explosion and fire hazards, as well as toxic, corrosive, and neutral fluids [1, 2]
Centrifugal pumps with elevated parameters, high power, and long service life have been designed in recent years
Their designs vary greatly
Roper Industries, Inc (USA) has patented the design of an integrated centrifugal electric pump (Fig 1a) for pumping
dirty fluids [3] The elongated shaft 8 of the electric motor 1 serves as the pump shaft, on which the impeller 2 is mounted
The fluid to be pumped is brought to the impeller axially through a suction pipe 5, and is removed from the casing 3 laterally
through a rising discharge pipe 4 The mechanical face seal 6 of the shaft 8 is installed in the pump casing cover 7 The
design features of the pump are: auxiliary spiral vanes 10 on the rear disk of the impeller and pyramidal lips (in cross section)
9 on the cover 7 During operation, the interaction of the vanes 10 and the lips 9 (Fig 1b) gives rise to vortex flows 11
that remove impurities from between the vanes and the lips The cooling of the face mechanical seal 6 improves and the wear
of the friction couple of the seal decreases The pump boasts a long service life
The centrifugal pump (Fig 2) manufactured by KSB AG (Germany) for pumping fluids with a high content of
solid impurities has a simple design [4] The open impeller 1 is mounted on the shaft 6 The rotating impeller shaft 6 and
hub 10 are tightly connected to rings 8 and 11, respectively, of the friction couple of the double face seal Rings 5 and 9
are inserted elastically in grooves machined in the cover 3, at different diameters axially displaced relative to each other,
and are self-adjusting The friction couple of rings 5 and 8 seal the space 7 with respect to the shaft 6 while the friction
couple of rings 9 and 11 seal the space 7 with respect to the impeller hub 10 The sealing fluid is fed to the space 7 through
the channel 4 in the cover 3
Bieri Pumpenbau AG (Germany) has manufactured two models (LE 403 and LE 504) of centrifugal pumps for hot
fluids [5] The pumps are equipped with a control system for smooth control of the shaft speed and the pump delivery
A high volumetric efficiency and a design that is convenient to operate distinguish the centrifugal pump made by
KSB AG (Germany) [6] The impeller is bolted onto the shaft A fixed sealing ring with a narrow shoulder between the rubber
sealing rings in the casing body and is fixed by pins and a locking ring to prevent turning; the locking ring is bolted to
the casing by means of a flange The fixed releasable connections between the locking ring and the casing as well as the
flange are tightly sealed by rubber O-rings A rotating ring is mounted on the bushing of the front impeller disk and together
with the sealing ring it forms a groove seal between the head and suction chambers of the pump casing