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The generation of process pumps UND/lII, complies with the specifications determined by ANSI/ASME B73.1 standards, last edition and continues being improved, offering to its users a superior pump, with high efficiency, excellent performance and a better MTBPM (Medium Time Between Planned Maintenance), which guarantees its reputation of high reliability pump in the toughest process conditions which allow the UND/lII pumps to present itself as one of the best process pumps of its class.


  • Capacities: up to 2000 m3/h.
  • Heads: up to 230 m.
  • Temperatures: -100ºC to 260ºC.Special executions to 370ºC.
  • Pressures: up to 26 Kg/cm2.
  • Power: up to 750 hp.


Owing to its qualities UND/lII pumps are applied in a great variety of processes and industries such as:


Transfer of a great variety of products, corrosive or not, loading and unloading of acids, transfer of organics, and pumping of products like sulfur, urea, liquified gases, solvents, monomers, polymers and other organic or inorganic chemical products.


In pumping aromatic products, light hydrocarbons, heat transfer products, top and botton reflux, gas oil, condensates, etc.


Digesters make up, pumping of green, black and white liquors, light pulps, coating products like clay and titanium dioxide, etc.


Waste acid recovery, gas scrubber service, acid transfer and recirculation, acid loading and unloading operations, etc.


Pumping of juices, suspensions, emulsions, industrial soup, heat transfer products, condensates, ammonium, sugar and alcohol.


In textile, pharmaceutical, pollution control, water supply and sanitation, dyeing, water chilling, condensates, acid recovery, recirculation of electrolytic and dying solutions, scrubbers, filter feeding, and other numerous industrial processes.

Design Features

1. SUPERBOX, enlarged seal chamber is standard in all UND/lII pumps. Increases the liquid circulation in the sealing box and consequently in the mechanical seal faces, reducing temperature, simultaneously pushing away from the same, solids contained in the pumped liquid, by centrifugal action, allowing also a better lubrication. The design allows the change from mechanical seal to packing and vice-versa in the field, without the need of special tools or additional machining. Completely open and taper bore sealing box chamber CONEBOX, offered optionally, allows the mounting of simple or dual cartridge seals providing high degree of lubrication or cooling. SUPERBOX or CONEBOX allows the adoption and mounting of the most different type of sealing systems for any specific operation condition. Simple, double, tandem, or dual cartridge type seals and its accessories or optionals are installed in these sealing boxes, who have big dimensions allowing also easy maintenance.

2.Open impeller is standard, pumps efficiently clean or charged liquids. Optionally the open impellers are supplied with an exclusive locking device which prevents the impeller looseness during accidental reverse rotation. Enclosed impellers are also supplied, subject to future consultation.

3.Bearings for 25,000 operation hours with maximum loads and continuous duty.

4.Maximum shaft deflection is 0,002″.

5.Labyrinth type seals optionally mounted in bearing housings positively prevent premature bearing failure caused by lubricant contamination.

6.Optional bearing frame cooling chamber.

7. Simple external impeller adjustment to keep the high original efficiency and long term energy saving.

8.Lubrication flexibility allowing constant level oiler and optionally, oil mist or grease lubrication.

9.Ductile iron adapter. Similar resistance to carbon steel. Higher security guarantee.

10.Casing, rear cover and adapter provided with adjusted fits, to assure the concentricity between shaft and sealing chamber, increasing the mechanical seals and bearings life.

11.Optionally available SAE 4140 heavy duty shaft, reduces L3/ D4 increasing shaft rigidity and therefore bearings and mechanical seal life. Improves durability.

12.Optionally double row thrust bearing, can be changed by two single row angular contact ball bearings 40° and O mounting. This mounting is indicated for processes where the mechanical assembly must support high operational duties.







CONEBOX SEAL CHAMBER: is the sealing chamber that provides the mechanical seals with the best operating conditions; best liquid recírculation and best seal face cooling. This type of sealing chamber is also self venting and self draining.

R TYPE BEARING FRAME::s an extra tough bearing frame providing a consíderable increasing in MTBPM (Mean Time Between Planned Maintenance) and consists in the use of an oversized shaft, duplex thrust load angular contact ball bearings, back to back and O mounted (as used in API pumps) and flinger oil lubrication. Such improvements allow pumps to operate with high specific gravity liquids and overhung belt drive applications. The mentioned factors normally increase shaft deflection causing premature failures in seals and bearings. The R bearing frame expands and fIexibilizes the application field of UND/lI pumps, for a long time trouble free operation.

FLEXIBLE LUBRICATION SYSTEM: allows the use of oil, oil mist or grease lubrication.

DD:the oil contamination by water or other contaminants is the main cause of a drastic reduction in bearing life of any pump. It is well known that 0,002% of clean water in the oil reduces 48% of the bearing life and that 6% of water causes 83% reduction in the bearing life, thus is extremely important avoid contaminants entering the bearing frame. The adoption of labyrinth or magnetic type seals instead of common oil seals, and venting exclusion greatly contribute to reduce this problem.

HEATlNG/COOOLlNG JACKETS:n casing, rear cover and bearing frame, allow the proper temperature control of pumped liquids and lubricating oil improving the mechanical and hydraulic pump performance. Jackets are cast-in in the rear cover and casing in one piece assembly.

HYDRODINAMIC SEALING:for tough appications, mainly such envolving abrasive and corrosive liquids, UND/lI can be fitted with DSV (Dynamic Sealing System) that allows the application of a repeller mounted between the sealing chamber and the impeller, eliminating the need of double mechanical seals or fIushing systems. Other advantages are that external seal water is not required, elimination of contamination and product dillution and drastical reduction of installation and operation costs. The repeller actuates like an impeller pumping out liquids and solids existing in the sealing chamber. Auxiliary sealing, packing or special mechanical seals operate when pump is shut down to prevent pump leakage. Retrofitting is available on request.

POSITIVELY LOCKING OF THE IMPELLER:is an improvement made to attend some process requirements in which the impeller can loosen from the shaft during accidental reverse rotation. Impellers are keyed and bolted according the usual setting systems.


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