It is finally happening… after promoting vibro installation of mono-piles for close to a decade, design institutes, developers and installation companies are becoming interested to use vibro hammers to drive their mono piles to depth. Driving mono piles with vibratory hammer is not only possible, it is also economical, fast, and with low impact to the marine environment.

Space on top of the monopile is at a premium! In 2019 ICE did a driving prediction for a 7000/ 8400mm diameter, 96m length weighing 1500t monopile. The soil profile consisted of layers of silt (Qc < 10 MPa) and sand (Qc > 10 MPa) and the target penetration depth was just over 40 meters. This is a colossal pile, but the square meters on which to place the 40.000kN centrifugal force needed to bring the pile into motion is only 21.98 sqm. We performed pile driving predictions for this monopile size and recommended the 2000M (42.992kN).

For the larger mono-piles you will need multiple vibro units working in synchronization. The base unit should be as big as possible so that it will be compact in size, and minimize the weight of the structure (which ensures maximum amplitude for driving the pile). The 2000M synchronizes four 500NF hammers together, in a design that only slightly exceeds the casing diameter (7880mm).

China’s marketing code forbids superlatives as the “largest” and we make no such claim, so we would like to challenge our readers to help us find a hammer that has more centrifugal in a more compact design than the ICE 500NF.

A 2000M needs 12.800 liters of hydraulic flow at 350 bar pressure. That is each minute! The hydraulic power needed for that kind of flow is 9040kW/ 12228HP. That needs four units of the ICE 3200 Power Pack (and deck space 4 x 22.7 sqm), also space for a hose reel to manage the 300 meters of hydraulic hoses needed to connect hammers with power packs.

This table shows the centrifugal force needed for different weights, as well as – and more importantly so – the hydraulic flow needed to power the set.

ICE has been in the vibro business for close to 50 years. Our designs always incorporate the following two principles, we recommend you pay attention to them when you chose your vibro tool:

1. The power pack should have a high ratio of HP to liters of flow.

2. The dynamic wright of the hammer (vibrating part + clamps and beams) should be as low as possible to maximize amplitude. That is why you often see our 250NF hammers with two 350TC clamps.

Further news:

Up-ending is the next up-coming, must-have, for installation of positioning frame piles, for quick dismantling before a weather event such as a typhoon, and also for mono-piles. Our design phase is finished, the DNV certification process is nearly completed and we expect to be able to upgrade our current users to upending capability in the second half of this year!

The 250NF is again proving popular for its reliability. Users mention their choice for the 250NF was often driven by its compact size. The deck-space necessary for the 250NF is limited as it is powered by a single ICE 1600 Power Pack. It’s also the hammer of choice for investors wanting to make money in the offshore wind installation business, a reliable performance allows investors a worry-free experience and the 20-30 year life expectancy of the equipment makes it a sound investment with high resale value.

Below we share some 2020 spring season offshore project pictures:

Please get in touch with our team if you would like to receive more information. We have a number of hammers available for rental or purchase from stock, we are happy to discuss your project needs and run a driving prediction for you!