Proudly celebrated its 20th Birthday in 2022, Sizabantu Piping Systems has grown from a trading company to one providing the marketing and sales function for a major South African thermoplastic pipe manufacturer Molecor. Sizabantu is a Southern African agent for a world leader Molecor in thermoplastic PVC0 pipe technology and is a joint venture partner in a production facility with Molecor in Richards Bay Industrial Development Zone.
Significantly, all the Sizabantu management throughout Southern Africa are qualified and highly experienced people who have been in the thermoplastic piping system industry for many years. They know quality products, customer service, product availability and commercial competitiveness are paramount in this highly competitive market.
They currently supply high quality, locally manufactured, thermoplastic piping system products into the Southern African market. The maximum diameter and pressure rating of the PVC0 pipes available is substantially greater than previously available and has enabled Sizabantu to compete in markets that were hitherto beyond the scope of previously available thermoplastic piping systems.
PVC pressure pipes
PVC pressure pipes were first used in Germany about eightyfive years ago. About sixty years ago PVC pipes were introduced into South Africa but were not enthusiastically received. Today, for example, more than ninetyfive percent of domestic sewerage reticulation pipes are PVC things have changed. Scientists, polymer technologists and processing engineers have enabled the Allowable Design Stress o for HDPE to be increased from 5 MPa to 8 MPa a substantial 60% increase. However, the increase in PVC's strength, enabled by improved technology, is even more substantial, increasing from 10 MPa to 36 MPa a incredible 260% increase.
In the 1970s. the PVC industry entered the mining services market following a successful project, led by Dr Ken Hart. A highimpact pipe PVCHI SANS 1283 was developed that satisfied the mining industry requirements and enabled PVC pipes to be used for underground services. Following on from this work, another development project, led by Mike Osry, developed PVCM SANS 9662 in the mid1990s by adding impact modifiers, commonly CPE Chlorinated Polyethylene, or Rubber Toughened Acrylics, or a combination thereof, to the PVC material to increase its impact strength. This enabled the material to exhibit "tough" characteristics that facilitated the reduction of the Design Coefficient C from 2 to 1.4 thereby increasing the Allowable Design Stress o from 12.5 to 18 MPa.
About forty years ago PVC0 Oriented Unplasticised Poly Vinyl Chloride SANS 16422 was developed. The molecular orientation process results in the improvement of physical and mechanical properties of the material. In the intervening forty years, there have been improvements in PVC0 material from Classification 315 material initially to Classification 500 material currently the nomenclature is ten time the MRS Minimum Required Strength of the material.
The latest PVC0 material, Classification 500, must have an MRS of not less than 50 MPa at 50 years, that with a Design Coefficient C of 1.4 gives a avalue of 36 MPa where a = MRS C. This is a substantial improvement, that is twice the Allowable Design Stress a of PVCM, made possible by improved inline production technology which, Sizabantu Piping Systems' Spanish technology partners Molecor excel at, and their TOM® 500 PVC0 pipes are produced locally in Richards Bay.
Innovation - TOM® 500 PVC-0
Innovation TOM® 500 PVC0 Innovation is one of Molecor's core values. With TOM® 500 PVC0 branded pipes, they have increased the range of PVC0 pipes from the previous limit of 315 mm diameter PN16 PN is the working pressure in bar to 630 PN25, with the MORP3136 system in 2010. Then in 2013 to 800 PN20, with the MORP3180 system.
Then to 1000 PN16 in 2020 and to 1200 PN16 with the MORP5012 system in 2021. Currently, the complete range of pipe diameters is available up to PN2.5 bar working pressure. These are exciting developments for the thermoplastic pipe industry, that has enabled it to compete in the large diameter high pressure pipe market, that was previously beyond its capability. These innovabons and the latest high technology polymers have enabled the service life of TOM® 500 PVC0 thermoplastic pipes to be greater than 100 years that is now the duration demanded by owners and consultants.
This is more than twice the ISO International Standards Organisation protocol requirement that thermoplastic pipes' design service life shall not be less than 50 years, which is 438000 hours on the polymer's Creep Rupture Regression Curve shown in Graphl. This property of TOM® 500 PVC0 thermoplastic pipes is one of the cornerstones of Sizabantu's success, together with its industry expertise, customer service culture and local manufacturing facility. These attributes have also enabled Sizabantu to grow their export business into Africa with one of its largest irrigation schemes, in Angola, an example of the success in this market.
They illustrate that despite the competitive nature of the market, they are succeeding and prove an axiom of today's world if you are standing still, you are probably going backwards. PVC pipe technology has improved substantially, and is continuing to improve, thereby giving the pipeline industry proven materials to use for large diameter, high pressure, bulk suppl pipelines, a market that steel and ductile iron has dominated historically.
PVC0 pipes are lightweight, have negligible friction increase over time, do not corrode, do not require expensive cathodic protection, give labour intensive emerging contractors equal opportunity to compete, have extremely high impact strength, low creep, low celerity and extremely low embedded energy maybe it is the material to help save the Earth? As government, metros, municipalities and local authorities strive to provide services to more people, with an everincreasing demand, and limited funding the advantages of using TOM® 500 PVC0 thermoplastic pipes and fittings becomes selfevident.
The future prospects appear to be promising for the product. More than 4 km of 1000 mm OD PN16 pipe have already been supplied and installed in Europe in 2021 and the first 1000 m OD pipes are expected to be supplied in South Africa in 2022. This will be another significant milestone for the South African thermoplastic pipe industry.
