http://www.engineeringnews.co.za
  SEARCH
Login
R/€ = 13.71Change: 0.04
R/$ = 11.04Change: -0.08
Au 1197.42 $/ozChange: -1.74
Pt 1206.50 $/ozChange: -23.50
 
 
Note: Search is limited to the most recent 250 articles. Set date range to access earlier articles.
Where? With... When?








Start
 
End
 
 
And must exclude these words...
Close Main Search
Close Main Login
My Profile News Alerts Newsletters Logout Close Main Profile
 
Agriculture   Automotive   Chemicals   Competition Policy   Construction   Defence   Economy   Electricity   Energy   Environment   ICT   Metals   Mining   Science and Technology   Services   Trade   Transport & Logistics   Water  
What's On Press Office Tenders Suppliers Directory Research Jobs Announcements Contact Us
 
 
 
RSS Feed
Article   Comments   Other News   Research   Magazine  
 
 
Jun 01, 2007

A corrosion solution to ‘pig-out’ on

Back
Engineering|Africa|Bateman|Bateman Engineering|Cleaning|Filtration|Flow|Magnaflux|Pipe|Pipelines|Pipes|System|Systems|Union Carbide Corporation|Water|Africa|South Africa|United States|Chemical Cleaning|Cleaning|Flow|Maintenance|Mechanical AndnChemical Cleaning|Pipe-pigging Technology|Pipeline Systems|PipelinenSystems|Pipes|Service|Steel|Systems|South African Government|Water|Pipe|Pipelines|Corrosion Protection|Pigging Technology|Pipe-pigging Technology|Thick And Ultrathick-film Technology|Thick AndnUltrathick-film Technology
Engineering|Africa|Bateman|Cleaning|Filtration|Flow|Pipe|Pipelines|Pipes|System|Systems|Water|Africa||Cleaning|Flow|Maintenance|Pipes|Service|Steel|Systems||Water|Pipe|Pipelines|
engineering|africa-company|bateman|bateman-engineering|cleaning-company|filtration|flow-company|magnaflux|pipe-company|pipelines-company|pipes|system|systems-company|union-carbide-corporation|water-company|africa|south-africa|united-states|chemical-cleaning|cleaning|flow-industry-term|maintenance|mechanical-andnchemical-cleaning|pipepigging-technology|pipeline-systems|pipelinensystems|pipes-industry-term|service|steel|systems|south-african-government|water|pipe|pipelines|corrosion-protection|pigging-technology|pipepigging-technology-technology|thick-and-ultrathick-film-technology|thick-andnultrathickfilm-technology
© Reuse this Significant time and money could be saved in the mechanical and chemical cleaning, surface preparation and recoating of underground water reticulation pipelines in South Africa, through the use of on-site pipe-pigging technology, says corrosion engineering specialist Corrocoat South Africa’s MD Louis Pretorius.



Pretorius says that maintenance of the internal surfaces of pipes is far more problematic than the external surfaces, owing in part to severe access constraints. South African municipalities have already identified that large amounts of water are being lost every day owing to pipe leaks caused by corrosion.



He says that when corrosion protection is required, it is often too expensive and time consuming to dig up underground pipes and is more practical and cost-effective to fix the pipes while they are underground.



Pipe-pigging technology has been designed to specifically tackle the effects of access limitations as well as the high costs of internal pipeline coating, maintenance and refurbishment.



Initially, mechanical scraper pigs are applied to the internal surfaces of pipelines that are too small for conventional blasting and painting techniques. It is used extensively to clean pipeline systems when they are too small for human access, too long to clean adequately or too expensive to have sediment blasted out with high-pressure water, says Pretorius.



The pigs are launched into the pipeline, through the use of either compressed air or the use of the medium already in the pipe, as a vehicle. Scraper pigs of different configurations remove the corrosion and sediment build-up in the pipes, resulting in an increase in flow through the pipeline.



The pigs are inserted into the pipeline either by the use of a fabricated Y-piece introduced into the pipeline or through the use of an in-line launcher bolted to the pipeline wherever there is a break. It is therefore used, for example, at a valve point or bend. Once the pigs travel through the pipeline section, they are caught at the other end using a pig ‘trap’. Electronic pig signallers assist with the pig detection and progress while in the pipe and indicate when foreign matter is to be expelled at the other end.



After mechanical cleaning, ‘intelligent pigs’ can be run for pipeline assessment, or the pipeline can be further cleaned in preparation for lining. Chemical cleaning involves repeated runs with detergents, solvents, and acids. When the pipeline is thoroughly clean internally, it is ready to be coated with a seamless internal liquid glass reinforced polymer (GRP) lining.



In normal circumstances, a pipeline would be taken out of service for 10 to 20 days while the corrosion protection oper-ation is being undertaken, says Pretorius. He says that in certain conditions, one can use the pigs for cleaning and desilting purposes, without stopping the flow of process liquid in the pipeline. This is accomplished by using the same liquid as a vehicle to carry the pigs, coupled with a filtration system to prevent any contamination of the process liquid further down the line.



Pipeline pigging has existed in the petroleum industry in South Africa for over 25 years. The technology has been modified and further developed for introduction to the water supply industry over the last 18 months.



“As a direct response to the South African government spending more money on infra- structure and reticulation, a company decision was made to further develop the technology with the aim of offering this service to the water-supply industry at national level,” says Pretorius.



South African company Magnaflux originally developed the technology in conjunction with US-based Union Carbide Corporation in the early-1980s, he says. The technology was then sold to another South African company, Bateman Engineering, and Corrocoat was enlisted to carry out joint research and development with Bateman for two years, researching pigging techniques and the use of better types of coating materials to seal leaking pipelines. Thereafter, Bateman withdrew from the sector after considering pigging technology as a noncore business and many of the Bateman staff involved in the pigging technology joined Corrocoat, says Pretorius. Corrocoat then developed the technology further, advancing thick and ultrathick-film technology, which is one step further than corrosion protection, he adds.



Thick and ultrathick-film technology involves a range of different aspects, including the relining of pipe lines for corrosion protection purposes and the application of ultrathick (6-mm to 12-mm) GRP linings, effectively creating a ‘pipe within a pipe’, in which GRP is created within an existing corroded steel pipe.

To create the GRP, a thick, liquid, cold-curing polymer resin, is applied to the internal pipe surfaces using specialised coating pigs, controlled by compressed air. The resultant GRP lining cures within 24 hours, effectively creating a polymer pipeline within the existing corroded steel pipe line. The GRP can be installed over distances of up to 45 km on a single pig run, says Pretorius. The coating technology has also evolved from 50

Edited by: Laura Tyrer
© Reuse this Comment Guidelines (150 word limit)
 
 
 
 
 
 
 
 
Other Corrosion and Tribology News
DUPLEX GRADE INCREASE Over the past thirteen years, the market share of duplex stainless steels worldwide has doubled
There is a growing willingness from industry to accept newer stainless steel materials, particularly duplex stainless steels, Southern Africa Stainless Steel Development Association Fabricator Sector chairperson Gary Crawford tells Engineering News. He says that, for...
OPERATIONAL LONGEVITY The most prominent benefit of the 8499/ 8470/ 8477/ 8478 series of stainless steel castors is corrosion resistance
Castor manufacturer Tente Castors South Africa introduced its stainless steel 8499/ 8470/ 8477/ 8478 series of stainless steel castors this year, says company technical manager Steve Thomas. The series comprises swivel, swivel with total lock, fixed and P67 plate...
PETER SHEPHERD South Africa’s big cities have had a severe impact on river systems, with increasing urbanisation compounding the situation
A significant amount of stormwater infrastructure in South Africa is insufficient to handle the country’s rapid urbanisation, according to consulting engineers and scientists SRK Consulting South Africa.
More
 
 
Latest News
Updated 2 hours 46 minutes ago Increased maintenance costs, poor rolling mill yields and strike action have widened Evraz Highveld Steel’s operating loss, from R149-million in the nine months ended September 30, 2013, to R483-million for the comparative 2014 period. The company added on Monday...
Updated 2 hours 47 minutes ago Energy Minister Tina Joemat-Pettersson has misled Parliament and should be suspended pending an investigation, the DA said on Monday. "Reports indicate that the minister was involved in recommending and appointing Mr Tshepo Kgadima as chairman of the board of...
More
 
 
Recent Research Reports
Defence 2014: A review of South Africa's defence industry (PDF Report)
Creamer Media’s Defence 2014 report examines South Africa’s defence industry, with particular focus on the key participants in the sector, the innovations that have come out of the sector, local and export demand, South Africa’s controversial multibillion-rand...
Road and Rail 2014: A review of South Africa's road and rail infrastructure (PDF report)
Creamer Media’s Road and Rail 2014 report examines South Africa’s road and rail transport system, with particular focus on the size and state of the country’s road and rail network, the funding and maintenance of these respective networks, and the push to move road...
Real Economy Year Book 2014 (PDF Report)
This edition drills down into the performance and outlook for a variety of sectors, including automotive, construction, electricity, transport, steel, water, coal, gold, iron-ore and platinum.
Real Economy Insight: Automotive 2014 (PDF Report)
This four-page brief covers key developments in the automotive industry over the past 12 months, including an overview of South Africa’s automotive market, trade figures, production and the policies influencing the sector.
Real Economy Insight: Construction 2014 (PDF Report)
This five-page brief covers key developments in the construction industry over the past 12 months. It provides an overview of the sector and includes details of employment in the sector, infrastructure and municipal spending, as well as insight into companies’...
Real Economy Insight: Electricity 2014 (PDF Report)
This five-page brief covers key developments in the electricity industry over the past 12 months, including details of State-owned power utility Eskom’s generation activities, funding and tariffs, independent power producers and prospects for the sector.
 
 
 
 
 
This Week's Magazine
JSE-listed real estate investment trust (REIT) Rebosis Property Fund achieved a distribution growth of 8.1% to 99.45c per linked unit in the financial year ended August 31, despite volatile market conditions.
JAMES ROBERTS The MOM incubator was designed to help babies in developing nations who were dying in conflict-struck nations or who do not receive hospital care
A low-cost, inflatable incubator won this year’s international James Dyson design award, which aims to encourage and inspire the next generation of design engineers.
The World Bank released its ‘Doing Business 2015: Going Beyond Efficiency’ report last month and ranked South Africa 43 out of 189 global economies for its ease of doing business, with Singapore topping the rankings.
Air Products South Africa officially launched its R300-million Eastern Cape air- separation unit (ASU), at its new manufacturing facility in the Coega Industrial Development Zone (IDZ), earlier this month. It is the second facility that Air Products launched in South...
BMW South Africa (SA) has signed a power purchasing agreement with energy company Bio2Watt. The offtake partnership will bring renewable energy to the carmaker’s Rosslyn plant, north of Pretoria.
 
 
 
 
 
 
 
 
 
Alert Close
Embed Code Close
content
Research Reports Close
Research Reports are a product of the
Research Channel Africa. Reports can be bought individually or you can gain full access to all reports as part of a Research Channel Africa subscription.
Find Out More Buy Report
 
 
Close
Engineering News
Completely Re-Engineered
Experience it now. Click here
*website to launch in a few weeks