9 minute read
Technical
THE BENEFITS OF 3D LASER SCANNING
What is 3D laser scanning, and can it be useful for plumbers today?
When traditional measurements are not appropriate or would not be practical due to time constraints, three-dimensional (3D) laser scanning is used. 3D laser scanning is a safe, non-contact, non-destructive process that digitally captures the physical shape of an object by using a laser light. This process represents the shape of an object with fine detail in 3D quickly. 3D laser scanning is the fastest, most accurate, and automated way to rapidly capture an accurate 3D representation of a real object, buildings, and locations for creating 3D drawing models. The scanning process is extremely fast.
Scanners are being used for topographic land and building surveying, mobile mapping, recording stages during construction, capturing as constructed services, tagging assets, ongoing services inspections, and monitoring maintenance.
Scanners are generally compact, portable, and are easily carried providing a colourised scanning range of 360 degrees, which involves the use of non-contact, non-destructive technology that digitally captures the shape of physical objects using a line of laser light.
The scanner measures fine details and captures free-form shapes to quickly generate highly accurate point clouds enabling the precise reproduction of the scanned object digitally.
There are various output formats that can be created such as AutoCAD, SolidWorks, Pro-Engineer etc., associated with outputs using DXF, DWG IGES etc., depending on the required application.
A point cloud is a set of X, Y, and Z coordinate data points (known as vertices containing millions of points) that represents a 3D shape or object from external surfaces around an object.
After the point clouds have been created, they are merged into one using specialised construction-specific software to create a 3D CAD model.
With a model of the scanned area, the designer now knows the position and elevation of everything within the scans to within a few millimetres. This allows designers to accurately prepare and design services pipe routes allowing for natural drainage flows etc.
The CAD model enables the precise reproduction of the scanned object, or the object can be modified in the CAD model to correct imperfections.
Operation of the 3D Laser Scanning System
• The 3D scanning head is first mounted on a tripod. • The scanning head and data tablet are turned on. • Details of the project are entered into the tablet together with the scan settings options, which includes a selection of a scan duration time from standard to high sensitivity depending on the resolution required. • The location of the first scan is determined from the station 1 node. • The scan is then commenced. • Once the scan has been completed capturing the images at station 1, the scanning head is then moved to a new line of sight, station 2. For standard scanning, a spacing of 10 metres is recommended. For a lessor quality resolution scanning a spacing of up to 80 metres can be used. • At the completion of all the scanning, the scanned data is then exported, and a 3D model can be created for the next phase of the design process.
Example of 3D Laser Scanning
Partial photo of a pool aeration system
3D scan of that area*
The Advantages of Using a 3D Laser Scanner
• Scanners are generally compact, portable, and are easily carried. • Overall the risks and costly mistakes associated with the traditional measurement processes are reduced by using 3D Laser Scanning. • The high-resolution 3D model is exactly accurate and helps to assist in surveying, mapping, and designing work. • Measurements can be taken digitally at a later date, from point to point of an object saving time over using a conventional measurement method. • Increased productivity by using 3D scanning, which can accomplish a lot of detailed documentation quickly, while it may have previously taken days for completion. • 3D scanning can be used in high hazardous or hard-to-reach areas without physically accessing an area while reducing costly safety measures. • Significantly higher quality control processes and measurements can be achieved with 3D laser scanning. • 3D modelling after the 3D laser scanning can highlight potential clashes and space for new or replacement equipment and services pipework. • The significant time associated with troubleshooting problems can be reduced by using accurate 3D laser scanning measurements, which provides savings associated with additional construction times on site. • At the completion of a project, accurate as constructed documentation can be produced showing a before and after comparison of the project works. • Ongoing benefits include building maintenance of plant and services together with refurbishments.
The Disadvantages of Using a 3D Laser Scanner
• It is difficult for a 3D laser scanner to measure any object surface that is out of the scanner’s line of sight. • The 3D laser scanner requires an amount of ambient light to scan an object. Other difficulties associated with scanning include humidity and ambient temperatures. • The initial cost of a 3D laser scanner can be between $50,000 and $150,000. Then there are costs associated with operator training and possible yearly equipment calibration.
In Conclusion
• 3D laser scanning provides an extremely fast, accurate, safe, non-contact, non-destructive process that digitally captures the physical shapes of an object creating 3D drawing models. • 3D modelling after the 3D laser scanning can highlight potential clashes and space for new or replacement equipment and services pipework. • Accurate as constructed documentation can be produced showing a before and after comparison of the project works. • Ongoing benefits include building maintenance of plant and services together with refurbishments. • The overall risk of costly errors and mistakes is reduced.
Article written by Ken Crase, First Vice President, Technical of the AHSCA QLD Chapter. Ph: 0432 066 770
*Photo and scan courtesy of Aqualogical.
Medical Gas Training
Now Available at PICAC Beenleigh
On 1 May 2021, a new modernised and rationalised fire protection licensing framework commenced in Queensland. These important reforms will further strengthen the building and construction industry and protect Queenslanders in the built environment.
To ensure the industry is supported through these changes, the Department of Energy and Public Works (DEPW) worked closely with the industry in the lead-up to commencement. As a result, some minor and technical amendments were made to improve the operation of the framework and the transition for industry.
What Are the Key Changes?
For most fire protection licensees, there will be little or no change to the work they are currently undertaking. However, changes have applied to some existing licensees, depending on the class of fire protection licence they currently hold. The new, streamlined licensing framework includes important transitional arrangements to support implementation.
In response to stakeholder feedback, further minor regulation amendments were made to support industry through the transition, including to:
• continue the existing scope of work for current hydrants and hose reels —inspect and test licensees for a further six months until 1 November 2021; • provide an option for electrical mechanics who can sufficiently demonstrate relevant experience to obtain a new contractor licence to install and maintain fire alarm systems with no upskilling required; • simplify the upskilling requirements for existing fire detection, alarm, and warning systems contractor licensees who also hold an electric mechanic licence; • clarify that licensed electrical mechanics do not require a fire protection occupational licence to inspect and test emergency lighting systems; and • make other minor and technical amendments to clarify terms and provide greater certainty under the new framework.
The current version of the Technical Qualifications for Licensing document has been updated to reflect: • the outcomes of a recent, comprehensive review by Artibus Innovation of the construction industry qualification framework; • commencement of Queensland’s new fire protection licensing framework; and • other minor updates, such as technical changes to reflect updated titles or codes for certain units of competency.
For more information, visit www.epw.qld.gov.au or www.qbcc. qld.gov.au/new-fire-protection-framework. MPAQ members can also call 07 3273 0800 to talk to our Technical Services team.
REMOVING HEATPUMPS
When a heatpump water heater is removed or replaced, what is being done with the old unit? A few members have posed the question to the MPAQ Technical team as how to properly dispose of the refrigeration units that contain refrigerant gasses.
Plumbers performing maintenance on water heaters often replace faulty or malfunctioning units. Disposing of the old unit has various options, as there is a scrap value if either you organise the disposal of the old steel/ copper tank for your customer to the local scrap dealer or rubbish tip, or the owner may choose to dispose of it themselves. This isn’t a complicated job as most scrap merchants/rubbish tips will take the unit as is, although some will pay a higher scrap value if the case and insulation are removed from the tank prior to scrapping. All well and good for your average storage cylinder, but not so with the average heatpump.
Heatpumps are comprised of a storage cylinder and refrigeration unit. Some units are integral and some are split (remote) from the cylinder, either way, the refrigeration unit cannot just be dumped or scrapped whilst it contains the refrigerant gas.
If the heatpump hot water system contains refrigerants that come under the Australian Refrigeration Council (ARC) Tick Licence Scheme, then there is a legal obligation for this gas to be recovered by an appropriately licensed person through the ARC, before the systems are discarded/recycled, where there is a risk that the gas may be emitted.
ARC encourages plumbers removing heatpumps to engage an ARC licensed technician to recover the gas prior to disposal of the systems to landfill or a waste transfer station.
Discharging fluorocarbon refrigerant is illegal under the Ozone Protection and Synthetic Greenhouse Gas Management Act 1989 and potential penalties of up to $54,000 for individuals and $270,000 for corporations may apply.
The recovery refrigerant from an end-of-life self-contained hot water heat pump unit must be carried out by a person with a relevant refrigerant handling licence issued by the ARC.
This recovery can be carried by someone with either of the following refrigerant handling licences: • RRR12 – Restricted refrigeration and air-conditioning licence – RAC Recovery • RSS03 – Restricted heat pump – split systems – installation and decommissioning licence: • RAC01 – Full refrigeration and air conditioning licence
There are several different types as detailed on the ARC website at: https://www.arctick.org/licensing/licence-types/
