PUMP DESCRIPTION

The electric pump mod. MM 100/125 for 65 and 130 T/h with horizontal split casing consists of a pumping body of the centrifugal type and of two opposite impellers. The division of the body is on the horizontal plane in order to reduce the axial thrust to minimum and to simplify maintenance. The electric motor is an asynchronous three-phases type, connected to the pump by means of an elastic coupling mounted on a frame structure which is made of electro welded steel. The special balancing of the pump and the specific construction of the base determine the sturdiness of the unit which permits to reduce to a minimum the structural noise level transmitted to the hull. Normally, the base is fixed to the hull after having introduced four resilient blocks which filter the noise transmitted by high frequencies.

APPROVAL TESTS

Testing carried out according to the standards shown in table UMM 1008, May 1984 edition, of Navalcostarmi: inspection and checking of integrity, test of hydrostatic pressure, test of voltage applied between electric phases, performance test, test of sealing and alignment, endurance test over 700 hours with more than 100 start-ups, test of operation in inclined position, detecting of self-induced vibrations and structural noise, impact and mechanical ambient vibration test, test of performances after impact and vibrations, disassembling and restoring. In particular these tests have been carried out according to the program transmitted by Mariperman from La Spezia, at which the delegates of Maripernam and Navalgenarmi of Turin attended.

MATERIALS

– Upper/lower body: GcuSn10Zn2Ni2 UNI 7013-72 alloy
– Shaft: stainless steel X2CrNiMo 1712 UNI 6900-71
– Impellers: GcuAl11FeNi4 UNI 5275-63 alloy

The hydraulic body presents special features: its structure ensures maximum reliability both for shock test and for possible corrosion due to electrical and fluids dynamics phenomena. Furthermore the hydraulics of the pump body permits regular running both for 65 T/h and 130 T/h flow-rate. All components are perfectly the same including the centrifugal impellers, a big advantage for spares parts supplies. There is practically no need for maintenance since the bearings are grease-lubricated forever. The sealing is a mechanical type and enables running of the pump in opposite direction without any specific problem. As requested by UMM 1008 standards, in case of emergency the mechanical seal can be replaced by a soft packing.

TECHNICAL FEATURES 130 t/h

Motor type: 250 M4
Power for continuous operation: 55 Kw
Steady state speed: 1775 rpm
Input power at full load: 96 A
Operation voltage: 440 V
Frequency: 60 Hz
Manometric head: 100 m
Capacity: 130 t/h
Pump weight: 1195 kg
Suction/delivery holes: 125/100 mm

TECHNICAL FEATURES 65 t/h

Motor type: 225 M4
Power for continuous operation: 45 Kw
Steady state speed: 1770 rpm
Input power at full load: 81 A
Operation voltage: 440 V
Frequency: 60 Hz
Manometric head: 100 m
Capacity: 65 t/h
Pump weight: 1050 kg
Suction/delivery holes: 125/100 mm