The demand for PVC has increased continuously in line with social development. Today worldwide consumption is approaching 30 million tonnes per annum 1 and global growth is expected to be more than 4 per annum. A significant proportion of this growth will be in PVC pipes which make up about 27 of the market for PVC in Europe.

PVC pipes are used in a wide variety of applications such as sewage potable water drainage and gas. In these areas plastics pipes often replace traditional materials. PVC continues to dominate the global plastics pipes market. In Europe PVC use in pipes was 1.5 million tonnes in 2002. The roots of industrial PVC pipe production date back to the 1930`s. The first pipes were produced in 1934 in the Bitterfeld-Wolfen chemical industry area. These pipes were used for different applications such as potable water pipes transparent food contact pipes brewery applications as well as industrial pipes chemical laboratory and plant applications. The annual pipe production capacity reached about 480 to 600 tonnes in 1941

. In parallel to the increasing production volumes the fi rst standards for plastic pipes were developed and products were made to meet them. Although the plastics industry is a relatively young materials segment the production of industrial volumes of PVC polymer and PVC-U pipes is now about 70 years old which is close to the predicted service lifetime of 100 years for PVC pipe applications. After the reunification of East and West Germany in 1989 and the involvement of Omniplast with pipe production in Bitterfeld it was possible to excavate and test PVC-U pipes from the early production years as they were still in use in 1992/3. A comprehensive series of tests on several of these old pipes and pipes produced in Troisdorf in the 1930´s and 1950´s was carried out and the results compared against the current norms. The results provide an excellent basis on which to compare the data from the original long term pressure tests with actual results from 60 year old pipes. This is not only an interesting reflection of the history of PVC pipe production and application as well as a confirmation of the long term performance predicted 60 years ago but it is also an important contribution to future PVC pipe developments.

 

The history of PVC started in 1835 when Regnault discovered vinyl chloride VC in the Liebig laboratory. But it took almost 100 years before first industrial production of PVC was started in 1928 in USA and 1930 in Rheinfelden Germany.

1835 Liebig and Regnault discovered VC 1878 Baumann observed the light-induced polymerization of VC 1912 Zacharias and Klatte obtained VC by the addition of HCl to acetylene 1913 Klatte polymerized VC with organic peroxides and described the processing of PVC as a substitute for horn and for films fibers and lacquers 1926 Griesheim-Elektron allowed the PVC patents to lapse this opened the door for other companies 1928 Union Carbide and DuPont copolymerized VC and vinyl acetate 1930 IG-Ludwigshafen copolymerized VC and vinyl ethers and acrylic esters. VC was emulsion-polymerized. PVC was stabilized with alkali salts. PVC was characterized by its K value Fikentscher. 1932 PVC was chlorinated IG-Bitterfeld 1933 Semon used phthalates and phosphates as plasticizers for PVC 1934 VC was suspension-polymerized Wacker. The capacity in 1945 was 35000 tons. A PVC pilot plant was opened in Bitterfeld 600 tons/year. Frazier Groff Union Carbide discovered alkaline earth soaps and Carbide Carbon Chemicals used lead salts as heat stabilizer for PVC. 1936 PVC was manufactured by Union Carbide and Goodrich . Dialkyl tin soaps were used as stabilizers by Carbide Carbon Chemicals. 1947 Barium cadmium calcium and zinc soaps were synergistically combined 1962 VC was bulk-polymerized in a two-stage reactor in 1975 a one-stage reactor was used by St. G obain and Pechiney Rhone-Poulenc. 

Milestones in PVC History The white PVC polymer from Rheinfelden production was called “Igelit” and could not be processed with machinery used for rubbers and Celluloid which where already processed at that time. After understanding that PVC needs temperature and pressure to melt it in 1934/35 the modification of existing rubber calenders and metal pipe ram extruders and the related processing conditions resulted in first calend ered crepe which were further processed into sheets pipes rods and profiles. PVC production volumes grew in Bitterfeld from 2686 tonnes in 1939 to 9202 tonnes in 1941.

 

By reference to old documents the PVC polymer was manually mixed with additives lubricants than it is known that calendered for 20 to 25 minutes at 160°C on a 2 roll mill to a crepe. This crepe was than manually rolled to a coil sausage of about 180 mm diameter and a length of 500 mm. This hot 160-165°C coil was fed into a hydraulic ram extruder with cylinder temperatures of 160/165°C and die-temperatures of about 200 – 230°C. These first discontinuously extruded pipes had lengths of 150 cm and 420 cm and were air cooled. This ram extrusion processes developed for making pipes in Bitterfeld in 1935 was transferred to two other production sites in Troisdorf and Eilenburg. In Bitterfeld pipes of 5 to120 mm diameter were produced during the early years. In 1941 it was possible to extrude PVC-U pipes up to 160 mm diameter and pipe production capacitiy increased in the three plants up to 600 t/year.

. From 1942 to 1945 the extrusion process was developed further and the first continuous single screw extrusion was used to convert PVC-granules into pipes. The development of counter-rotating twin screw extruders started some years later. At the same time as PVC pipe production started the properties of the pipes were investigated and different application areas for the first pipes were selected. The following properties were tested regularly: density tensile strength elongation at break and impact strength/ductility. Official reports characterized the PVC-U pipes as follows: “PVC-U pipes have a specific weight of 1.4 g/cm³ a softening temperature of 80 to 85°C a tensile strength of 500kg/cm² 50N/mm² and an elongation at break of 15 to 20. The product is physiologically blameless resistant against . Vinidur pipes left axis and fittings right axis at 20°C

 

It is inflammable a good electrical insulator and a poor thermal conductor.” On the basis of the first technical characterization the PVC-U pipes were in 1935/36 directly u sed in different applications: the first water pressure pipes were layed in the cities of Bitterfeld and Salzgitter pipes were used in the chemical industry for corrosive liquids and they were used for in-house potable water pipes as well as for food contact applications such as brewery pipes. Transparency and resistance against encrustrations made it a successful product in food contact applications. Beside the practical experience with the pipes from first production comprehensive systematic laboratory investigations had also been done. Buchmann 7 and Krannich 8 documented relevant properties including creep strength chemical resistance and welding performance. In 1941 the first diagrams from hydrostatic burst pressure test s and long term creep test were available figures 1 2 and the first PVC-U pipe DIN-standards were established figures 3 9 10 11. 

 

Initial feedback from the early years PVC-U pipes from the early production years 1935/36 were installed immediately and after the first couple of years of experience with these pipes the following reports from 1938 are documented: - experience with 3.9 tonnes of pipes in the Merseburg ammoniac plant: “Igelit pipes were used with good success in contact with different acids alkalis and gases in particular sulfuric and chloric acid” - experience with 969 m of PVC-U pipes in the Wolfen film plant: “Igelit pipes are layed for 2 years in Inorganic Laboratory Wiss. Chemicals in contact with the pipes are: HCl of every concentration NaOH up to 20 SiCl 4 NaCl-solution sea water distilled water formalin vapors of chloric acid with alcohol.

Until now the pipes have not caused any negative comment with regards to the chemical resistance. The laying is easy because of the simple processing.” - statement of the Berlin police president department V: “There are no concerns about the use of the Mipolam tubes for the movable part of carbon dioxide pressure pipe system.” - statement from the Institute of Fermentation and Starch Production Berlin 1940: “…contact of beer over 3 weeks with the Vinidur Pipes MP has not caused any change or deterioration of taste and smell or visible changes. Therefore these pipes can be used in b eer tap equipment without any restrictions…” - statement from the Institute of Fermentation and Starch Production Berlin 1941: “… surprisingly there are no noticeable changes neither on the Vinidur pipes nor on the brandy or spirits of different concentrations which were in contact under rigorous testing conditions contact time large surface….” 

Results on PVC-U pipes from the early production years after long term use PVC-U pipes from the first production years 1935-1941 hydraulic ram extrusion have been installed in different regions in Germany mainly for potable water pressure pipe systems and sewer systems. About 400 flats in Bitterfeld have been installed with such pipes. Another example is a potable water pipe system in Steinfurth Wolfen which was operated at 3.5 to 6 bar and was still in use 1992. Also test pipeline systems had been installed in the first production years e. g. in Leipzig Dresden Magdeburg Berlin Hamburg Köln Heidelberg and Wiesbaden. These pipelines were operated at pressures of up to 6 bar with pressure peaks up to 18 bar at a frequency of 10 pressure changes per minute. All these pipelines have demonstrated good performance. A lot of them were destroyed in the Second-World-War but some are still in use

 

In 1961 two different Mipolan pipes 16 x 1 .6 mm which were installed in a house in Hamburg in 1937 were removed and tested after 23 years of use. A Mipolam pipes from installation in Hamburg produced in Troisdorf 1937 B Typical values from 13 Igelit pipes from installation in Bitterfeld produced in Bitterfeld in 1935 – 1940 D Typical values from Omniplast pipe from 1993 production.

After the reunification of East and West Germany in 1989 and the involvement of Omniplast with pipe production in Bitterfeld 23 pipe samples figure 3 have been removed from different installations after more than 50 years of use. These pipe samples have also been tested and their properties compared to a pipe produced in 1993.

 

 The “Bitterfeld” pipes were tested at DVGW Technologie Zentrum Karlsruhe 1994 against the standard KTW drinking water recommendations and the results obtained demonstrate that the performance of these pipes is similar to PVC pipes made today. Long term hydrostatic pressure tests have also been done on the PVC -U pipes from the first production years after 23 and about 50 years of use “Hamburg” and “Bitterfeld” pipe respectively. Another two pipes from Bitterfeld have been tested and these were long enough to provide several test samples each while the first series of “Bitterfeld pipes” were tested as individual pipes at different pressures

 

 Although the “Bitterfeld pipes” from 1935 to1940 are all different and were used in different areas the variation in results is very similar to variation seen in the FNK round robin tests done in 1966 on one production batch these also showed a varia tion of 3 decades in the burst pressure. Therefore the results of all single pipes from the Bitterfeld production have been compiled in one hydro static pressure test diagram . A comparison of the data from the pressure test with the requirements of the first standards DIN 8061 and 8062 from 1941 indicate that even pipes from the first production years met these long term requirements although the results are below today’s requirements and typical contemporary data

The two pipe samples from production and use in Bitterfeld samples C 24.1 – 25.5 were in operation as potable water pipes in houses for 53 years at 4 to 5 bar operating p ressure. These 9 pipe samples were used for hydrostatic burst pressure tests at 60°C . The regression line from the long term hydrostatic pressure diagram extrapolated to 10 6 h indicates that a hoop stress of 2.8 N/mm 2 is predicted . This demonstrates that these pipes would last another 100 years of operation even at 7 bar and 60°C operating conditions. If these data are plotted into an “Arrhenius diagram” then at temperatures between 20°C and 40°C these pipes would last another 100 years operating at 9 to 14 bar with a safety factor of 1.5. This means that even if the operating pressure was doubled to 8 or 10 bar this pipe would easily last the 100 years as a potable water pipe with a safety factor of 1.5. Figure 5: 60°C long term hydrostatic burst pressure test of 2 Bitterfeld pipes samples C: 24.1 – 25.5 3. Summary and outlook All the results even from the first produced PVC-U pipes which have a service life of about 50 years demonstrate in an impressive way the excellent durability of these plastic pipes. The development of PVC polymers compound recipes and processing machinery for pipes production today results in much better long term performance of PVC-U pipes compared to the early PVC-U pipes which is reflected also in the newer standards. The best reflection of the positive experience and long term performance is the fact that globally PVC pipes are the most widely used plastics pipes.

 

\ For new developments in PVC-U pipes such as new stabilizer types this long term experience forms an excellent basis against which to compare and correlate performance data. This will ensure that the excellent durability demonstrated in practice by the old pipes will in the future equalled and even exceeded by newly developed PVC-U pipe products. Acknowledgement: This paper leans heavily on the work and interpretation of Mr. Egon Barth. His assistance has been invaluable for this paper.

References: 1 D. Thompson: “Life The Universe and Everything ” 4th Global PVC Conference Amsterdam 18/19th November 2003. 2 ECVM: “PVC in Building and Construction” February 2004 www.evcm.org 3 R. E. Nowack et al: „60 Jahre Erfahrungen mit Rohrleitungen aus weichmacherfreiem Polyvinylchlorid PVC-U KRV Nachrichten 1/95 1995 4 E. Barth: „Die Geschichte der Kunststoffrohre“ SKZ-Fachtagung „Kunststoff- rohre in der Trinkwasserversorgung“ Würzburg March 1998 5 M. Kaufmann: “The history of PVC“ MacLaren London 1969 6 D. Braun: “Polyvinyl chloride on the Way from the 19th Century to the 21st Century ” published online 24 December 2003 in Wiley InterScience www.interscience.wiley.com 7 W. Buchmann: Z. VDI Bd. 84 1940 pages 425 – 431 8 W. Krannich: „Kunststoffe im technischen Korrosionsschutz“ J. F. Lehmann - Verlag 1943 9 DIN 8061: „Kunststoffrohre aus Polyvinylchlorid Rohrtyp -Eigenschaften und Richtlinien für die Verwendung“ Juli 1941 10 DIN 8062: „Kunststoffrohre aus Polyvinylchlorid Rohrtyp -Maße“ Juli 1941 11 DIN 8063: „Kunststoff-Rohrbogen aus Polyvinylchlorid Rohrtyp“ Juli 1941 12 DVGW Technologiezentrum Wasser Karlsruhe: „Untersuchungsbericht zur Prüfung von PVC-hart-Rohren auf hygienische Unbedenklichkeit nach KTW - Empfehlungen March 1995

 

Source: http://www.authorstream.com

Part 2 in the link below:

https://en.tankymineral.com.vn/-pvc-water-pipe-history-technology-history-of-pvc-and-pvc-pipes-how-to-make-pvc-pipe-part-2--342579?preview=1

 calcium-carbonate-for-pipes-pvc-products-1537061406-4307325

Tan Ky Mineral Processing Joint Stock Company- Leading manufacturer of calcium carbonate  for pipe making

www.tankymineral.com.vn

Mob/what'sapp: +84 86.89.89.350

Email: talia.tkmineral@gmail.com

Related posts

Imerys acquired the consolidated calcium carbonates business of Vimal Microns and Vee Microns. The new entity operates under the name of Imerys Carbonates India Limited
Imerys acquired the consolidated calcium carbonates business of Vimal Microns and Vee Microns. The new entity operates under the name of Imerys Carbonates India Limited
Calcium Carbonate uses for Agriculture
Calcium Carbonate uses for Agriculture
Omya and Imerys Carbonates EMEA announces price increases across its Calcium Carbonates portfolio
Omya and Imerys Carbonates EMEA announces price increases across its Calcium Carbonates portfolio
Qingyun Shenggang launches a 20,000 ton / year tissue machine in Shandong, China
Qingyun Shenggang launches a 20,000 ton / year tissue machine in Shandong, China