Tonal Sound from Onshore Drilling Rig Top Drive Unit

Over the last 10 years onshore drilling for hydrocarbons in the Taranaki region of New Zealand has reached new levels of intensity. As exploration expanded between 2005 and 2015 so too did the potential conflict with rural communities. Noise emissions from onshore drilling rigs is generally well understood and can be mitigated accordingly. However, the top drive unit of onshore rigs can emit strong tonal noise. This paper summarises the results of detailed analysis in determining whether other drilling processes are influential in the causation of tonal noise from the top drive unit. The results of this analysis were also used to provide the rig operator guidance as to how to modify drilling, especially at night, to avoid generating tonal noise arises that may cause disruption to rural communities.