Allweiler SNE80ER42 Casing Insert & Screw Spindle Set

Allweiler SNE80ER42 Pump Casing Insert + Screw Spindle Set (for SNH & SNGH Series) — New Surplus

The Allweiler SNE80ER42 casing insert and screw spindle sub-assembly is an OEM-standard hydraulic rebuilding core designed for high-demand maritime and industrial three-screw positive displacement pumps. Engineered to restore internal volumetric efficiency across SNH (horizontal footprint, in-line suction/discharge) and SNGH (flanged/bracketed casing configurations) series, this drop-in bundle eliminates the need to replace entire cast pump bodies.

The assembly comprises the central, nitrided drive screw (Part No. 122), two hydraulic-driven idler/driven screws (Part No. 123), and the factory-machined casing insert liner (Part No. 2). By matching tight radial clearances and thread flank geometry, this assembly eliminates backflow slippage in high-temperature heavy fuel oil (HFO), low-sulfur marine gas oil (MGO), and marine turbine lube oil systems.

Model Identification Code: SNE 80 ER 42

• SNE: Screw Pump Sub-Assembly Insert Kit (E-type standard internal insert)
• 80: Theoretical casing displacement / pump frame size diameter index
• E: External/internal bearing and balancing piston mechanical configuration
• R: Right-hand drive rotation (Standard clockwise rotation when viewed toward drive shaft end)
• 42: Pitch/lead angle profile index of the intermeshing spindle thread geometry

Manufacturing Part Numbers (MPN) & Cross References

• Primary MPN: SNE80ER42 / SNE 80 ER 42
• Compatible Pump Series: Allweiler SNH 80, SNGH 80, SNF 80, SNS 80
• OEM Component Level Breakdown:
  • Casing Insert: Component Pos. 2
  • Power / Drive Spindle: Component Pos. 122
  • Idler / Counter Spindles: Component Pos. 123 (Matched Pair)
• Cross-References: CIRCOR Allweiler VM 618 series, IMO ACG/ACD equivalent frame retrofits, MPCC Allweiler 80-series rotating overhaul packs

Technical Specifications

Key Features

1. Complete Pre-Clearanced Fluid Core: Includes the matched casing insert sleeve and all 3 precision-ground spindles, restoring factory clearances without line-boring the host pump casing.
2. Hydraulic Axial Thrust Balancing: Integrated balance pistons offset high back-pressures in the delivery chamber, allowing idler screws to float hydrodynamically on fluid films with zero metal-to-metal flank contact.
3. Extreme Viscosity Handling: Engineered to displace fluid matrices ranging from low-viscosity fuels (1.2 cSt light MGO) up to high-viscosity residual oils and heavy lube stocks (up to 5,000 cSt).
4. Non-Turbulent Laminar Chambers: Symmetrically profiled thread geometry transfers fluid continuously in sealed, non-pulsating axial chambers, minimizing line vibration and cavitation noise.
5. Modular Replacement: Designed for fast field turnaround during dry-dock schedules or at-sea overhauls; slide out the worn insert cartridge and slide in the SNE80ER42 assembly.

Applications

• Marine Main Engine Lubrication: Sump circulation, crosshead oil, camshaft lubrication, and reduction gear injection on MAN B&W, WinGD, and Wärtsilä systems.
• Fuel Oil Conditioning & Boosters: High-pressure feeder and booster modules for marine fuel lines handling HFO, LSFO, and Ultra-Low Sulfur Diesel (ULSD).
• Purifier Feed & Sludge Transfer: Feeding centrifugal fuel and oil separators under elevated process temperatures.
• Hydraulic Control Units: Electro-hydraulic steering gears, controllable pitch propellers (CPP), windlass packs, and stern ramp winches.
• Industrial Oil Systems: Power turbine jacking systems, boiler burner feed, paper mill calendering lubrication, and transformer oil pumping.

Frequently Asked Questions

Can I install the SNE80ER42 insert in an SNH pump without replacing the outer casing?

Yes. The Allweiler modular design allows the SNE80 cartridge to install directly into the existing outer casing of SNH, SNGH, and SNF series pumps, provided the host casing’s internal seating surfaces remain within original mechanical tolerances.

What is the distinction between SNH and SNGH pump variants using this insert?

The difference lies in the external casing casting and port layout: SNH pumps feature an in-line suction and delivery configuration, whereas SNGH pumps use a modified branch geometry (often a U-turn or offset design). The internal hydraulic rotating assembly—the SNE80 insert and spindles—remains identical between both designs.

What is the significance of the “42” designation in the model number?

The number 42 indicates the specific pitch and thread helix angle of the power and idler screw spindles. Using an ER42 spindle set ensures exact displacement per revolution and maintains the motor load profiles specified in your vessel’s original technical manuals.

Does this insert set include bearings and the mechanical seal?

This assembly covers the core hydraulic pumping unit: the three-spindle set (one drive screw, two idler screws) and the pre-bored casing insert. Bearings (Pos. 34), mechanical seals (Pos. 83), and peripheral paper/elastomeric gaskets are service wear parts that should be ordered concurrently based on your fluid temperature profile.

How do I check if my existing spindles require replacement?

Spindles should be replaced if you measure radial clearance between the outer screw diameter and the casing insert bore exceeding factory service wear limits (typically >0.15 mm on frame size 80), if deep tracking or galling is visible along the screw flanks, or if the pump exhibits an unexplained drop in delivery pressure at normal running temperatures.