Aug 03, 2012
Rubber company develops new pressure vessel lining methodBack
1st Wear Corrosion Protection Rubber|Africa|Africa|Australia|Germany|South Africa|The Netherlands|Chemicals|Cured Rubber|Metal|Metal Fatigue|Products|Rubber|Rubber-lining Pressure Vessels|Uncured Rubber|Andre Van Rooyen|Required Technology
© Reuse this
The method involves putting uncured rubber into the vessel and using the vessel as the curing unit, as opposed to using rubber that has already been cured, or putting the vessel in an autoclave to cure the rubber.
“Uncured rubber is soft and pliable, making it easy to work with and to mould it to the shape of the vessel, as opposed to cured materials, which often require the use of elastomeric fillers at joints.
“Using the vessel as the curing unit has many advan-tages. The rubber bonds better to the metal and forms perfectly to the shape of the vessel, which is important when the vessel is used to hold chemicals that will corrode the metal,” says Van Rooyen.
Other advantages are that uncured rubber is cheaper than cured rubber and, owing to the better bonding properties of the rubber, less repairs are needed. This can also potentially extend customers’ guarantees.
The method was applied successfully to a pressure vessel for an Australian company, which is using the vessel as an acid washing column, in December last year.
“It took me about a month to carry out the tests and ensure this method was possible. I suggested it to the customer. The company was satisfied, so much so that we will soon be lining a second vessel, using the same method.
“The second vessel is in the design phase and should be delivered to us at the end of this year or early in 2013,” says Van Rooyen.
He is hoping to increase awareness of this new method in South Africa, as it will ben-efit businesses that use vessels.
Although the method is suc-cessful, Van Rooyen says there were challenges during the development phase.
“Laws on the use of pressure vessels in the country have become more stringent in the last five years, so much so that a swimming pool pump is now considered a pressure vessel.
“We have government-approved inspection auth-orities (AIAs), which have to certify a vessel and provide a government plate for it before it can be used. If a pressure vessel does not have a manufacturer’s plate on it, you will have to redesign and recalculate that vessel, with an AIA as a wit- ness, as well as with a design engineer to do the recalcula-tions,” he explains.
He adds that redesigning a pressure vessel entails the design engineer doing detailed drawings of the vessel, material identification and X-rays on all welds.
“This can cost anything from R75 000, just for the design engineer’s part of the job. The result is that many vessels are used illegally in the country, which can be potentially dangerous.
“So the method becomes tricky on older vessels, as they will need to be redesigned and recalculated. Factors like metal fatigue and corrosion also have to be taken into consideration when working with older vessels,” says Van Rooyen.
He does not believe in throwing away or destroying older vessels.
“They should be recalculated and downgraded to work at a lower pressure, but many people and inspectors do not know that this can be done.
“We do it all the time at WCP Rubber. We have a vessel that had been manufactured in 1966 that is still fully operational after we downgraded it to work at a pressure of 8.5 bar instead of its designed 10 bar,” he notes.
Another challenge is that many well-qualified professionals in the industry have emigrated to countries like Australia. The few who are left, he says, demand high salaries that rubber lining companies often do not have the budget for.
Van Rooyen believes developing new methods is a way for South Africa to compete with the world.
“Africa has some of the best raw materials and minerals in the world, readily available at all times. We also have the required technology; however, our ability to produce innovative products is hampered by our high labour costs and lack of experts.
“If we use our materials and technology to our advantage, we can fulfill our potential and attract more business to our shores. “This will mean more money and economic growth for the country, as well as fewer strikes and fewer unhappy workers,” he says.
Van Rooyen plans to introduce another new development that he believes will transform the rubber industry.
“I have contacted some people in Holland and Switzer-land, as I plan to develop a way in which a building can be used as a curing unit. “It will be something similar to a bunker that is able to withstand enough pressure to be used as an autoclave. “This would mean any piece of machinery could be rubber-lined and cured,” he says.
He notes that this has been attempted once before in the early 1940s, in Germany, but a conclusion was never drawn and the attempt was unsuccessful.
“I believe it is very possible and it will open doors for the rubber industry. “We may have the funds available to purchase a factory or building of some kind in the future and will hopefully be testing this then,” states Van Rooyen.
Edited by: Chanel de Bruyn© Reuse this Comment Guidelines (150 word limit)
Other Vessels, Heat Exchangers, Tanks and Containers News
Updated 1 hour 39 minutes ago Fluid-handling design and supply company Mechinox South Africa (SA) has recorded a downturn in the demand for custom-built shell and tube heat exchangers, while more energy efficient shell and plate, as well as modified- plate and modified-frame plate heat exchangers...
Updated 1 hour 39 minutes ago Heat generation company Steam Generation Africa will soon be delivering two containerised mobile steam plants to mining projects in North and Central Africa, respectively. “There is an increasing demand for saving space and ensuring the mobility of boilers units in...
Updated 1 hour 39 minutes ago The local pressure vessel industry has been under significant strain for the past several years and there are no signs of improvement, at least not for the remainder of this year, industry body the Pressure Equipment Manufacturers Association (Pema) executive...
Recent Research Reports
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.
Real Economy Insight: Road and Rail 2014 (PDF Report)
This six-page brief covers key developments in the road and rail industries over the past 12 months, including details of South Africa’s road and rail network and prospects for both sectors.
Real Economy Insight: Steel 2014 (PDF Report)
This four-page brief covers key developments in the steel industry over the past 12 months. It provides an overview of the global and South African steel and stainless steel markets, South Africa’s major steel producers and events that have shaped these markets.
This Week's Magazine
Updated 1 hour 35 minutes ago South African construction company Group Five says work on the rehabilitation of the 800 km stretch of the Plumtree–Mutare highway, in Zimbabwe, should be completed by the end of this year. Giving evidence before the Parliamentary Porfolio Committee on Transport...
Updated 1 hour 38 minutes ago The Space Operations division of the South African National Space Agency (Sansa) revealed on July 17 that it had supported the successful launch of the US National Aeronautics and Space Administration’s Orbiting Carbon Observatory-2 (OCO-2) satellite on July 2. The...
Updated 1 hour 38 minutes ago Phase 1A of Johannesburg’s Rea Vaya bus rapid transit (BRT) system should carry around 42 000 people a day, while it was been expected that Phase 1B, rolled out last year, would add another 60 000 daily passengers. However, the entire system is currently carrying...
Updated 1 hour 38 minutes ago A stormwater project in Bedforview, east of Johannesburg, has stalled for eight months after project managers in the Ekurhuleni municipality resigned and municipal managers were placed on special leave without designating replacements. Construction to reinforce the...
Updated 1 hour 38 minutes ago The design of the Beit Bridge border post is the biggest impediment to efficient freight movement between Zimbabwe and South Africa, says Cross-border Road Transport Agency CEO Sipho Khumalo. Beit Bridge is the busiest border post in Africa. A research study on the...