The heavy duty pump design is based on the latest edition of API610, international standard for centrifugal pumps for petroleum, petrochemical and natural gas industries. The pump complies to Machinery Directive 2006/42/EC and is ATEX self-certified according to EN13463.
Outer barrel and cover
The outer barrel is a cylindrical body designed for the required working pressure. The cover is secured to the outer barrel by shear rings.
The inner case consist of two identical halves, axial split designed with double volutes for radial balance.
The axial split joint of the inner case is fine machined to provide sealing of the two halves without a gasket.
The full discharge pressure surrounds the two inner case halves, putting the two halves under compression. Thus only light inner case bolting is required for assembly purposes.
The nozzle flanges are ANSI ring joint type machined in the barrel surface without neck.
Standard orientation is top top on horizontal version. Other types and orientations are optional.
The end covers are designed with ample space for installation of dual mechanical seals. A bleed off line is included in pump design to give suction pressure in both seal chambers.
The shaft is of ample size to transmit the required power and to prevent excessive deflection and is machined and ground to required dimensions.
The impellers are opposed in order to provide axial balance. They are assembled to the shaft by shrink fit.
The case wear rings are held in place by grooves in the case. A pin inserted in the case ring and seated in the case split prevents rotation of the rings.
The rings have different diameters to adjust the axial balance.
The low pressure wear rings are axially split to allow dynamic balancing of complete rotor.
Bushings and sleeves
There is two sets of shaft sleeves with bushings along the shaft. One throat bushing and one bushing between mid-stage and last stage impellers. The wear parts are made of composite material in a steel bushing or stellited stainless steel. Alternatively Silicon carbide wear parts can be delivered as an option for abrasive liquids..
All gaskets are of confined type, either plain o-rings, o-rings with back up rings or spring energized u-seal.