ZR07 Slewing Drive Planetary Gearbox — Right-Angle Bevel-Planetary, 2-4 Stage

De EP-ZR07 slewing drive planetary gearbox fills the critical torque gap in the ZR slewing drive series between the light-duty ZR03 (2,500 Nm) and the heavy-duty ZR10 (11,500 Nm). At 5,000 Nm continuous and 11,000 Nm peak, the ZR07 handles the workload of medium excavators, concrete pump boom mechanisms, and marine deck equipment without the weight and cost penalty of oversizing to the ZR10 frame.

The ZR07 ratio architecture concentrates its 24 options in the 3-stage and 4-stage configurations, with the 4-stage offering 18 ratios from 99.67 to 430.22. This density of choice in the high-ratio region makes the ZR07 particularly well-suited to applications where precise speed matching is important — a nearby ratio means a smaller motor can be used, reducing both the drive package cost and the electrical infrastructure requirement.

DIN 5-6 precision gear grinding for consistent mesh quality

Medium Excavators (15-20 Tonne Class)

Hydraulic excavators in the 15-20 tonne operating weight range generate upper-structure slewing torques of 3,000-5,000 Nm during standard digging cycles. The ZR07**2 at ratio 7.96 driven by a 63-80 cc/rev axial piston motor at 250 bar delivers the speed and torque density these compact machines require, while the 11,000 Nm peak handles the aggressive operator inputs common in demolition and rock-breaking applications.

Concrete Pump Boom Rotation

Truck-mounted concrete pump booms with 32-42 metre reach generate slewing torques of 2,500-4,500 Nm during pouring operations with the boom partially extended. The ZR07**3 at ratios 33:1-49:1 with a B510 fail-safe brake provides smooth, controlled rotation during pour placement and secure holding when the boom is parked between pours. The IP67 sealing resists concrete splatter and pressure-washer cleaning.

Marine Deck Cranes and Davit Mechanisms

Ship-mounted deck cranes and lifeboat davit slewing mechanisms operate in permanent salt spray, thermal cycling, and vessel motion environments. The ZR07**4 at ratios 99:1-180:1 provides the controlled low-speed slewing these marine applications demand, while the right-angle output geometry integrates cleanly into the tight mechanical envelopes typical of shipboard crane pedestals. The zinc phosphate and polyurethane coating system provides ISO 12944 C4 corrosion protection.

Why does the ZR07 2-stage have only one ratio while the ZR06 2-stage has five?

The ZR07 uses a different internal gear geometry optimised for the 5,000 Nm torque class. At this load level, the bevel input stage and first planetary stage are larger, leaving less dimensional freedom for the second planetary stage to vary its ratio. The single 2-stage ratio (7.96) represents the one gear combination that meets both the torque requirement and the housing envelope constraint. For applications requiring a 2-stage ratio other than 7.96, the ZR06 (lower torque) or ZR10 (higher torque) may offer a better match.

How does the ZR07 compare to the ZR06 for the same application?

The ZR06 and ZR07 share the same 4,000-5,000 Nm torque class but differ in their internal architecture. The ZR06 offers 40 ratio options (wider flexibility) while the ZR07 offers 24 options with a different ratio set. In many applications, both frames will have a suitable ratio. The choice then comes down to which ratio is closer to the calculated optimum, which affects motor sizing and energy consumption. Contact our engineering team with your target ratio and we will recommend the frame that provides the closest match.

Is the ZR07 approved for marine classification (DNV, Lloyd, BV)?

The standard ZR07 is manufactured under ISO 9001:2015 with full material traceability. For marine applications requiring classification society approval, we supply units with witnessed material testing, witnessed factory load testing, and the documentation package needed for type approval. Lead time for classification-witnessed units is typically 8-12 weeks. Specify the classification society and notation required at the time of enquiry.

What happens if the brake engages during rotation?

Spring-applied brakes on the ZR07 are designed as holding brakes, not dynamic (friction) brakes. Engaging the brake while the output shaft is rotating will cause rapid wear of the brake disc and generate heat that can damage the brake housing and adjacent seals. The hydraulic or electrical control system must ensure that motor speed is reduced to zero (or near zero) before the brake engages. For applications requiring controlled deceleration, use the motor or VFD for dynamic braking and the spring-applied brake only for final static holding.

Concrete pump fleet, 8 units with ZR07**3 at 42.41 ratio. We have been running them for about a year across multiple sites. The B510 brakes work reliably and the IP67 housing handles the daily concrete splatter and pressure-wash cleaning without any issues. One unit got buried in wet concrete up to the mounting flange when a hose burst — cleaned it off and it kept running. Could not say that about the previous drives.

Deck crane slewing drive planetary gearbox for a 65-metre offshore supply vessel. Specified ZR07**4 at 147.57 ratio with B610 brake and marine-grade coating. The material certificate package was thorough enough to pass DNV survey on the first submission. Unit has been operating in the North Sea for 7 months without maintenance. The coating is holding up well in the salt environment, though we will monitor the breather valve area closely as that tends to be the first corrosion point on any gearbox at sea.

Replacement slewing drive on a 17-tonne excavator. Performance-wise no complaints, the machine swings as well as with the original unit. Installation was straightforward with the BF02 hydraulic flange. The reason for 4 stars is the drain plug position — on this particular excavator frame layout, the drain plug ends up in a spot that requires removing the belly plate to access for oil changes. A second drain port option on the opposite side of the housing would solve this for about 30% of excavator installations. Overall good value.