Leistritz L3MF-60/96 IF0KT-0-S Triple Screw Pump

Leistritz L3MF-60/96 IF0KT-0-S Triple Screw Pump

The Leistritz L3MF-60/96 IF0KT-0-S is a positive displacement triple screw pump for marine applications for the transfer of lubricating oils, hydraulic fluids and distillate fuels. In the pump, the liquids are held in precision-molded tight chambers. A hardened and ground power rotor is used between two double threaded idler spindles. This continuous axial fluid movement of the rotors eliminates shearing, pulsation and turbulent agitation making it perfect for machinery rooms and heavy industrial fluid loops.

This unit is of an internal bearing arrangement (Design Code: I) which means the radial grooved ball bearing is lubricated by the pumping fluid directly without the need for external grease or oil baths. Its internal architecture counteracts hydraulic forces to reduce fluid pressure just in front of the shaft seal to suction-line pressure levels. This specific pressure relief protects the mechanical seal from back pressure damage. This unit has been subjected to rigorous workshop static and dynamic pressure testing to prove casing integrity, seal seat tight under full operating pressure and volumetric tolerances to factory standards.

Model Info:

Manufacturer Model Number (MPN): L3MF-60/96 IF0KT-0-S

Part Number Cross-References: Leistritz 66672.010, L3MF060096IF0KT0S, HMC-1236

Technical Specifications: Leistritz L3MF-60/96 IF0KT-0-S

Key Features

1. Hydraulically Balanced Triple Screw Profile: Removes axial thrust loads from the internal grooved ball bearing, significantly reducing mechanical wear and structural load distributions during high pressure duty cycles.
2. Low-Pulsation Fluid Displacement: Fluid cavities move axially in a smooth continuous fashion to prevent flow shearing and system agitation for an ultra-quiet decibel operating footprint (nominal 65 dB(A)).
3. Suction-Isolated Shaft Sealing Zone: A deaeration bore which is gun-drilled internally conveys fluid from behind the seal directly back to the suction chamber, such that the mechanical seal is only exposed to suction pressure conditions.
4. Robust internal lubrication array: Powered solely by the pumped media, this reduces external service steps and removes the risk of contamination from external greases.
5. Rigid Monoblock Housing Design: Precision cast arrangement for either side-by-side or specialty top-flange configurations, managing variable thermal and longitudinal pipe expansion stress vectors.

Applications

• Marine Main Engine Lubricating Systems: Acts as the primary or standby oil circulation pump for low and medium-speed marine diesel propulsion units.
• Fuel Oil Transfer & Booster Modules: Handles high-volume transfer of Marine Gas Oil (MGO), Marine Diesel Oil (MDO), and heavy lubricating base oils between settling and day tanks.
• Industrial Hydraulic Power Units (HPUs): Supplies constant, pulse-free pressure to critical fluid power distribution networks and large-scale hydraulic machinery.
• Power Plant Turbine Lube Systems: Circulates oil to high-speed steam and gas turbine generator bearings, ensuring clean thermal control and hydro-dynamic lifting pressure.

Model Coding Identification & Breakdowns

L3MF – 60 / 96 I F 0 K T – 0 – S
│ │ │ │ │ │ │ │ │ └── Special Feature Code (Tested Casing & Seals)
│ │ │ │ │ │ │ │ └────── Design Series Generation 0
│ │ │ │ │ │ │ └────────── Mechanical Seal Type (with internal recirculation)
│ │ │ │ │ │ └──────────── O-Ring / Elastomer Composition (Vitonic/High-Temp Flank)
│ │ │ │ │ └────────────── Built-In Bypass/Safety Valve Profile (0 = Without Valve)
│ │ │ │ └──────────────── Mounting Configuration (F = Small Mounting Flange)
│ │ │ └────────────────── Bearing Design (I = Internal Bearing / Fluid Lubricated)
│ │ └─────────────────────── Pitch Helix Dimension mm (96mm Axial Stroke)
│ └──────────────────────────── Nominal Power Rotor Size Diameter mm (60mm)
└────────────────────────────────── Pump Series Code (Flange-Mounted / Medium Pressure Range)

Equipment Compatibility

The Leistritz L3MF-60/96 series mounts interchangeably alongside equivalent high-performance triple screw equipment frames. It serves as a direct upgrade or operational swap-out for the following marine and industrial systems:

• IMO Pump Equivalents: ACE 038N2 NTBP, ACE 038K4 NLBP, and ACD 025L6 series positive displacement units.
• Allweiler Alternatives: Similar footprint three-screw lubricating modules within the SM/SPF framework.
• Drive Coupling Systems: Flexible direct-drive couplings bored to accept standard cylindrical shafts with parallel keyway paths. Suitable for frame connections to 4.0 kW / 4.8 kW marine electric induction motors.

Operational & Alignment Guide:

1. Cold Start-Up & High Viscosity Management: If the auxiliary engine room environment drops low enough to elevate fuel or lubricating oil viscosity beyond normal operating bounds, never force the pump to run dry. The internal bearing depends entirely on the fluid film for hydrodynamic cooling. Manually pre-fill the suction housing with pre-warmed fluid before engaging the electric motor drive.
2. Laser Alignment Tolerances: While the L3MF series utilizes a robust monoblock design, direct flexible coupling configurations require meticulous dial indicator or laser tracking. Ensure an axial gap buffer clearance between 1/8″ and 1/4″ exists between the two coupling coupling hubs to provide breathing room for the system’s thermal elongation under full heat conditions.
3. Protecting the Keyway During Seal Overhauls: When performing mechanical seal replacements, cover the parallel keyway edge slots meticulously with thin adhesive tape before easing the radial shaft seal ring into its final home. A single microscopic nick on the elastomer sealing lip from an exposed metal shoulder edge guarantees a recurring drip leak once suction head pressure builds.