The BB3 type, KB3S and KB3D pumps are axially split case volute casing multistage pumps which are conforming to API610. These pumps are suitable for wide applications in upstream / midstream / downstream, applications in petroleum, petrochemical, gas industry, fertilizer and allied chemical industry as a centrifugal pump as well as hydraulic power recovery turbine (HPRT). The discharge pressures are designed up to class 2500 and suitable for suction pressures up to 80 bar (g).
For alternative specifications contact us.
The casing is multistage ring section, single casing, diffuser type centerline mounted on sturdy support pedestals.
The discharge casing is a structure prudently designed and fabricated of carefully selected material for high temperature and high pressure services. Particularly the balance chamber is of a unique construction achieved with year’s long experience. The tests are secured at shaft centre for freedom from thermal effects.
Inter stage Casing is simplified in construction for freedom from thermal deformations, and is overall finished for minimum frictional loss in fluid. The interfaces at the respective stages are super finished for perfect seal without packing used.
Rodelta can also provide casings which are designed for maximum allowable working pressure and 2 times API nozzle loads and if required Rodelta can also provide casings which are designed for maximum allowable working pressure and 4 times API nozzle loads. If required Rodelta can also provide steam tracing/insulation to the casing, when high temperature application is involved. This is to avoid unwanted heat transfer or to avoid any accident/hazard due to high surface temperature of casing.
Nozzle orientation arrangement
Suction & discharge nozzles are designed in Top-Top configuration. Suction nozzles are available in 150/300 class flange rating as per ANSI B 16.5 whereas Discharge nozzles are available in 300/600/900/1500/2500 class flange rating (as applicable depending upon maximum working pressure). Flanges of suction & discharge nozzles are raised faced with a serrated finish. Nozzle loads are physically tested at our test bed centre by applying forces.
Top-Top nozzle arrangements, a tapped and plugged vent is included in Rodelta’s scope of supply. Drain holes are NPT and vent sizes are NPT. Seal circulation lines are ½” NPT, irrespective of discharge sizes. All provided connections are shipped with plugs made of materials compatible with the casings, unless otherwise specified. Additional connections can be provided for Quenching, Cooling water inlet & outlet & Warming line when specified.
Liquid gasket is employed for sealing.
Stuffing box is deep enough to accept various seal designs including tandem and double seals. Water cooled or Jacketing stuffing box designs are available at extra cost when specified or required. Cooling arrangement is provided for stuffing box depending upon the pumping temperatures.
The impeller are of closed type, finished overall that a maximum hydraulic efficiency can be obtained. They are perfectly balanced, both dynamically and statically. The impellers are all located in one direction, with thrust balanced by drum. Impellers shall not be individually located along the shaft. Impellers are balanced individually as per ISO 1940 Gr 1/Gr 2.5.
If required Non – destructive like dye penetrant test on Machined surfaces or Radiography test can also be provided on impeller.
Impeller Wear Rings
The impeller wear rings are held on impeller with an interference fit and secured in positions with set screw to ensure positive fitment.
Case Wear Rings
The case wear rings are inserted in the casing and the gland cover with a interference fit and secured in position with set screws.
Note: – wear ring flushing arrangement can also be provided when solid particles are present in operating fluid.
Shaft and shaft sleeves
The hooked shaft sleeve is axially secured against a shoulder on the shaft by the impeller nut and keyed to prevent radial rotation. The shaft sleeve also extends beyond the seal end plate to positively identify seal leakage. A gasket is provided between the sleeve and the shoulder on the shaft.
Bearing housing and bearings
Bearing housing is horizontal split type for easy removal of bearings for inspection. The antifriction bearings are lubricated through an integral splash type system accompanied with oil ring. Radial bearings are Sleeve type bearing and thrust bearings are angular contact ball bearing in back to back arrangement or tilting pad are provided as standard. The bearing housing has an extra large oil reservoir to provide sufficient oil capacity. Oil level control is done by constant level oiler at DE & NDE brg. Housings. It is furnished with a constant level oiler which includes a mechanically lockable adjustment and a protecting wire cage. The following optional features are available at extra cost.
Hydrodynamic thrust bearings are provided when energy density ratio is greater than 4.0 mill kW/minas per the API standard
Radial Bearing – Oil Ring
Thrust bearing – Oil Ring/Forced Oil (Forced Oil is required if Linear velocity at bearing sleeve is >14 m/sec. and or tilting pad type bearing is used
Requirement of cooling to bearing housing basically depends on pumping temperature and the linear velocity of bearing sleeve.
Axial thrust generated by the pump during running condition is balanced completely by balancing disk and drum arrangement.
Two types of Balancing methods:
The balancing method to be adopted shall be decided based on the suction pressure and the temperature rise in the balancing chamber at minimum flow.
As a standard oil bath lubrication is provided to lubricate the bearing. In case of tilting pad bearings (hydrodynamic bearings) forced feed lubrication is provided. Lubrication system comply the latest API 614 chapter 2 & chapter 3 and also can fulfil customer specific requirements. Lube oil tanks are supplied separately mounted on base plate. Lube oil tanks can also supplied with in-built baseplate. Lubrication oil used is ISO VG46.
Interstage tapping can be provided to accommodate LP & HP flow.
Lift out devices for axial lifting is not required in these pumps.
Metal to Metal fit is without confined controlled compression gasket or O ring.