ENGINEERING, IT, INNOVATION

  Press room  

Creation of as-build three-dimensional model at the Leningrad NPP by means of laser scanning

02.07.2012

Club 3D. Innovative ingineering design

Vitaliy Kononov, Vladislav Tikhonovsky, Nikolay Salnikov, Dmitry Dorobin

Introduction

Nowadays JSC Concern Rosenergoatom performs activities on three-dimensional modeling of NPP units within the framework of creation and improvement of the information database pf preparation and decommissioning of NPP units.

At the same time at most NPPs there is often no urgent and sufficiently detailed design documentation. Moreover such a documentation is not available at design organizations due to various reasons. As a result the available documentation does not fully correspond to the current state of the NPP unit, that is the three-dimensional models, created on its basis, have a low degree of accuracy and credibility.

So the urgent task is fast and qualitative obtaining of credible information about the current state of the object.

NEOLANT company has performed a pilot project on creation of three-dimensional models with use of the laser scanning technology for JSC Concern Rosenergoatom, found out labor-output ration and determined organizational and technical aspects of its application for nuclear power objects.

The Leningrad NPP (LNPP) has been selected as an object for performance of the pilot project, since earlier NEOLANT developed the information system of database for decommissioning (ISDBD) for it, which included three-dimensional models of the main buildings of the plant.

The main purpose of the ISDBD of the LNPP units is accumulation, long-term storage and presentation in the form convenient for specialists of the information, required and/ or influencing performance of activities on decommissioning. Access to the information of the electronic archive and visualization of the information are ensured by use of three-dimensional design models of the NPP objects.

Three-dimensional models of the main buildings and sites of the first and second stage LNPP were created by NEOLANT company specialists. In the course of creation of the three-dimensional model of the main building more than 10 thousand drawings of the architectural and construction part of the building, of the auxiliary buildings, of the reactors, of the technological, etc. were processed.

Fig. 1. Example of the cloud of points, obtained as a results of laser scanning of the industrial object
Fig. 1. Example of the cloud of points, obtained as a results of laser scanning of the industrial object

Based on the results of the pilot project the three-dimensional models of the NPP objects were updated according to laser scanning results.

Laser scanning technology

Nowadays the laser scanning technology is widely used for three-dimensional modeling of complex industrial objects at enterprises of oil and gas, power, etc. industries throughout the world, including Russia.

The laser scanning allows to obtain space information about the object by means of laser radiation. Based on the obtained data coordinated of the objects are calculated automatically, and as a result the clod of points is formed (fig. 1).

Modern technologies of laser scanning are assumed to obtain the clouds of points with an error not exceeding 1 mm in the enclosed space, and 2 to 3 mm in the esplanade. There is a possibility of obtaining results with higher accuracy too (up to 1 to 5 mm), but this entails significant increase in the costs of activities.

Fig.e 2. Cloud of points of the industrial site of the first stage LNPP
Fig.e 2. Cloud of points of the industrial site of the first stage LNPP

Since the clouds of points to be scanned correspond to the original quite accurately, then the three-dimensional models to be obtained will also correspond to the real state of the objects in sufficiently greater degree irrespective of the level of their detailing. It is practically impossible to achieve this degree of urgency by the method of reengineering of data.

Course of laser scanning

The NEOLANT company has performed laser scanning of the main buildings and sites of the first and second stage LNPP.

Such objects as facades of the main buildings, buildings and structures, approach channels and discharge canals, cable bridges and pipeline trestles, openly located equipment, motor roads, walkings and railways, storages of salvage and other wastes, openly located at industrial sites were scanned.

The scanning process consisted of the following stages:

  • Scanning parameters were being established, priorities were being determined (the area of survey, the distance to the objects were being determined, the necessary resolution was being determined, data filters were being specified,,etc.).
  • Scanning with respective optimal adjustments was being made, the process was monitored on-line .
  • Facades of the buildings and individual sections of industrial sites of the first and second LNPP were being photographed (in order to clarify details and create textures).
  • The industrial sites of the first and second LNPP were being photographed in order to create spherical panoramas.
  • The primary analysis of the obtained data was being made (control measurements, assessment of the fullness of photography, etc.).
  • The data obtained from various points of scanner standing (ScanWorld) were being sewn into integrated clouds of points, describing the buildings and industrial sites of the LNPP. The data were being filtered and processed in a proper way.
  • The resulting integrated clouds of points were being positioned according to the existing 3D models of the buildings of the industrial sites of the first and second LNPP.
  • The database of the clouds of points was being formed in Cyclone IMP format.

According to the results of activities on laser scanning resulting integrated clouds of points of the objects of the first and second stage LNPP were obtained, which were resulted to the coordinate system of the initial models of the industrial sited. The laser scanning data in the plan and on height have been oriented and brought into compliance with the models of the buildings.

Updating of 3D models

Fig. 3. Combination of the existing model with the obtained cloud of points on building 402A of the first stage LNPP
Fig. 3. Combination of the existing model with the obtained cloud of points on building 402A of the first stage LNPP

The NEOLANT company performed work on updating the existing 3D model of Building 401 and of the industrial site of the first stage, of building 601 and of the industrial site of the second stage Leningrad NPP with account of laser scanning data. As a result 3D as0build models were obtained, which correspond to the current state of the object for the moment of laser scanning.

Figure 3 shows combination of the initial model with the data of the laser scanning on the cable tray and vent pipe of the industrial site of the first stage LNPP. The existing model of the industrial site is shown in violet, the cloud of points is painted as per reflection intensity. The divergence on the vent pipe and cable tray is shown in red arrows.

At the same time the divergence between the initial model and the laser scanning data reaches a few meters. In order to correct this divergence all the objects of the initial model were replaced to their actual location.

Further the analysis of the correspondence of the initial model of the industrial site to the actual object composition of the LNPP was performed as per the laser scanning data. In the course of the analysis the following unconformities of the object compos ition of the initial 3D model and of the resulting integrated cloud of points of the industrial site were revealed:

  • Objects missing on the initial model.
  • Objects, the models of which do not correspond actual geometrical parameters.
  • Objects, actually missing at the industrial site, but which are contained un the 3D model.

The 3D models of practically all existing objects of the industrial sites of the first and second LNPP were updated (fig. 4).

Conclusion

Fig. 4. Updated model tanks, combined with laser data. The model corresponds to the cloud of points
Fig. 4. Updated model tanks, combined with laser data. The model corresponds to the cloud of points

The pilot project, performed by the NEOLANT company, corroborates effectiveness of laser scanning as a technology of creation of accurate and credible 3D NPP models, reflection of urgent arrangements of the equipment, systems and structures. This is especially important in case of absence of updated and sufficiently detailed design documentation or development of as-build documentation.

It is profitable to use laser scanning for solving the tasks of operation, which require high accuracy and updated model. The technology allows to continually monitor changes as a part and in the configuration of the small-sixe equipment and pipelines of small and average diameter, which take place significantly oftener, than for large-size equipment and large diameter pipelines.

The NEOLANT company has acquired a necessary experience of performance of activities on laser scanning and creation of as-build models. The pilot project has shown effectiveness of laser scanning technology application for solving the tasks of construction, and decommissioning in nuclear industry.


Share this page:

Back

NEOLANT: news and events

Press room