Zollner ZET Horn 131/141/90/110AC Piston, Con-Rod & Crankshaft Set

Zollner ZET Horn 131/141/90/110AC Piston, Connecting Rod, and Crankshaft Set

The Zollner ZET Horn 131/141/90/110AC Piston, Connecting Rod, and Crankshaft Set is the complete core reciprocating drive assembly engineered for ZÖLLNER Signal GmbH electric piston-type marine sound emitters. In an electric ZET-Horn, a 5.5 kW 3-phase AC motor drives a pair of wear-resistant upgraded steel gearwheels. This rotational torque transfers directly to the crankshaft, converting rotary motion via the connecting rod into high-frequency linear oscillation of the piston inside a vertically suspended cylinder.

The rapid oscillation of this piston assembly excites the air column inside the acoustic horn projector at its exact resonant frequency (90 Hz, 110 Hz, 130 Hz, or 140 Hz depending on horn geometry). This mechanical displacement generates a 138 dB to 143 dB (1/3rd-octave band at 1 m) acoustic signal with strong upper harmonics, ensuring long-range audibility compliant with COLREG 1972 Annex III. Replacing the piston, connecting rod, crankshaft, and bearing set restores full compression and eliminates mechanical knocking or running-in lag (standard running-in period < 0.15 seconds).

Model Details

• Manufacturer: ZÖLLNER Signal GmbH (Kiel, Germany)
• Compatible Whistle Series: ZET-Horn AC Series (131AC, 141AC, 90AC, 110AC)
• Component Assembly Scope: 1x Reciprocating Piston, 1x Connecting Rod, 1x Eccentric Crankshaft, and Matched Crankcase/Wrist-Pin Bearing Set
• Manufacturer Part Number (MPN) / Reference: OEM ZET-Horn AC Drive Kit (Reference Catalog Docs: 06100084EN3 for 131/141AC; 06100085EN3 for 90/110AC; Control Box Drawing Ref: 01415158).

Technical Specifications — Zollner ZET Horn 131/141/90/110AC Reciprocating Assembly

Compatibility

• COLREG Class I Vessels (Length ≥ 200 meters):
  • ZÖLLNER ZET-Horn 90AC (90 Hz fundamental frequency)
  • ZÖLLNER ZET-Horn 110AC (110 Hz fundamental frequency)
• COLREG Class II Vessels (Length 75 meters to < 200 meters):
  • ZÖLLNER ZET-Horn 131AC (130 Hz fundamental frequency)
  • ZÖLLNER ZET-Horn 141AC (140 Hz fundamental frequency)
• Land-Based Industrial Warning Systems:
  • ZET-Horn 90AC, 110AC, 131AC, and 141AC installations at refineries, bunker stations, airports, and power plants.

Part Number Cross-References

• ZÖLLNER Datasheet References: 06100084EN3 (ZET-Horn 131/141 AC), 06100085EN3 (ZET-Horn 90/110 AC)
• Associated Control Box Reference: ZÖLLNER Standard Control Box Drawing 01415158 (380/440V supply, 115/220V control)
• Associated Parent Equipment Cross-References:
  • ZÖLLNER ZET-Horn 90 AC (BSH 4615/6021094/09)
  • ZÖLLNER ZET-Horn 110 AC (BSH 4615/6021095/09)
  • ZÖLLNER ZET-Horn 131 AC / ZET-Horn 141 AC

Features

1. Oil-Free Grease-Lubricated Architecture: Engineered to operate continuously with standard marine bearing grease rather than liquid sump oil, eliminating oil leaks in vertically suspended mast installations.
2. Seawater-Resistant & Hardened Metallurgy: Manufactured from non-corrosive marine alloys and wear-resistant upgraded steel to resist salt-laden condensation and high cyclic fatigue.
3. Sub-0.15 Second Acoustic Response: Precision-balanced crankshaft throw and low-friction piston tolerances ensure immediate resonant air column excitation (< 0.15 s) for crisp Morse and fog signaling.
4. Field-Serviceable Onboard Design: Modular construction allows marine engineers to replace the entire reciprocating assembly at the masthead using standard shipboard metric tools without dismantling the acoustic projector.
5. Multi-Model Cross-Compatibility: Standardized drive geometry fits both Class I (90/110AC) and Class II (131/141AC) ZET-Horn drive housings, simplifying fleet spare parts inventory management.

Frequently Asked Questions

Does this piston, connecting rod, and crankshaft set fit both Class I and Class II Zollner ZET-Horns?

Yes. This reciprocating drive assembly is engineered to fit the drive housings of both Class I models (ZET-Horn 90AC and 110AC for vessels 200 m and above) and Class II models (ZET-Horn 131AC and 141AC for vessels between 75 m and 200 m).

What type of lubricant is required for the Zollner ZET-Horn crankshaft and piston assembly?

The ZET-Horn AC series uses an oil-free crankcase design that requires steady lubrication with high-grade marine bearing grease rather than lubricating oil. Using liquid oil will result in leakage due to the horn’s vertically suspended cylinder configuration.

Can this assembly be installed while the ZET-Horn remains mounted on the vessel’s mast?

Yes. ZÖLLNER designed the ZET-Horn AC series with a modular crankcase that allows shipboard engineers to exchange the piston, connecting rod, crankshaft, and bearings in situ using standard onboard metric tools, provided electrical power is safely isolated.

Is this kit compatible with the Zollner ZET-Horn 70AC or Makrofon air horns?

No. The ZET-Horn 70AC uses a larger 130 kg heavy-duty drive frame with different dimensional tolerances, while Makrofon models are pneumatic or steam diaphragm whistles that do not utilize a motor-driven piston and crankshaft.

What are the symptoms of a worn piston or connecting rod assembly in a ZET-Horn?

Common indicators include a noticeable drop in sound pressure level (failing to reach the 138 dB or 143 dB COLREG threshold), delayed signal startup exceeding 0.15 seconds, metallic knocking from the masthead during operation, or tripped thermal overload relays on the 5.5 kW drive motor due to increased mechanical friction.