Vivax Metrotech vLocDM, Руководство пользователя

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3.3 Planning a Survey
Surveys will vary greatly depending on type of terrain, accessibility, condition of pipeline, type of pipeline and
coating type.
The first step of undertaking any survey should be to obtain information about the stretch of pipeline to
be surveyed. More work at this stage may well save time and effort later. Obtaining maps showing route
information, CP stations, sacrificial anodes and cross bonding points will be of great help.
The transmitter should be capable of transmitting from one CP station to another, so although not absolutely
necessary, plan to have the previous and after CP stations disconnected from the stretch of pipeline to be
surveyed. Remember that the pipeline is not protected whilst the survey is being undertaken, so unnecessary
downtime of CP stations should be avoided.
Choose the survey interval to match the condition of the pipeline. In areas where the coating is particularly poor,
a survey interval of as little as 10m may be desirable. However, if the coating is in very good condition and the
distance between CP stations is many km, it may be better to choose a survey interval of as much as 200m.
Taking measurements at large intervals will enable the surveyor to quickly asses the condition of the pipeline
and subsequently identify areas that require further inspection at closer survey intervals or detailed analysis
using the A-frame Fault Finder accessory.
WARNING
Parts of the pipeline may be crossing road junctions and may even follow the route of
roads. Obtaining accurate results from the vLocDM requires full concentration from
the operator. It is therefore essential that correct traffic management is undertaken at
these points to avoid poor results or injury to the operator. Safety should always be
the first concern.
3 Introduction