Pipeline solutions for the future You are here Home pageCheck the cast iron pipes / ZM lining Share Facebook Twitter E-mail Check the cast iron pipes / ZM lining SAINT-GOBAIN PAM GERMANY 1. Cleaning and checking After galvanizing, the pipes are led over combined plastering and test sections, on which the remains of the socket core sand are removed and, if necessary. existing burrs are ground. A 100% inspection of the pipes is then carried out. First there is a visual inspection and the checking of the socket and spigot ends with the help of limit gauges. A ring fold test, in which a section of the ring is extremely ovalized, provides information about the degree of ferritization established during the annealing process and the ductility of the tubes. In the following, an automated wall thickness measurement with ultrasound and a pressure test with water ensure that the pipes meet all requirements with regard to safety against bursting. 2. Leak test All pipes, whether for pressure lines or gravity sewers - which have passed the previous controls - are subjected to a leak test with water. The minimum test pressure depends on the nominal size and wall thickness class. For pressure lines, the lowest test pressure is 25 bar and the highest 50 bar. Sewage pipes are tested with at least 11 bar. 3. Cement mortar lining The pipes for water supply and wastewater disposal systems are lined with cement mortar in order to ensure that the hydraulic properties remain the same during the service life of the systems. Deposits and incrustations are permanently prevented by the ZM lining. The pipes for water systems are lined with cement mortar based on blast furnace cement and the sewer pipes with cement mortar based on alumina cement. Defined quantities of mortar are pumped into the pipes. They are then closed at the socket and spigot end and brought to specific revolutions per minute by drive rollers and drive rollers. The mortar experiences a centrifugal acceleration which corresponds to 75-130 times the acceleration due to gravity. Due to this acceleration and additional vibrations, the mortar is distributed, compacted and smoothed on the pipe wall. The specifically heavy particles are oriented towards the cast wall while the lighter ones settle on the inside, ie the fine grain particles form the smooth surface of the cement mortar lining. Centrifugation drives off most of the feed wastewater. The spinning process gives the mortar a dense mortar structure. 4. Tire of cement mortar lining The pipes, lined with cement mortar, are placed in special ripening chambers in order to achieve a controlled hardening. these chambers are set to a predetermined atmosphere such as humidity and temperature. Under these conditions, the mortar must mature for a specified time. Slide show PRODUCTS Download Technical data sheets Catalogs E-catalog INFORMATION News Events Press area credentials glossary SERVICE Academy / training courses ABOUT US Contact Career youtube / Pamline TV LinkedIn COMPANIES Saint-Gobain Group Saint Gobain PAM International DATA PROTECTION IMPRINT CONDITIONS COOKIES SITEMAP WE USE COOKIES ON THIS SITE TO ENHANCE YOUR USER EXPERIENCE By clicking the Accept button, you agree to us doing so. No, give me more info OK, I agree No thanks