Hi Vithana,  To decide ...

Hi Vithana,

 To decide which joints to use (external or internal) you must first confirm the pipeline pressure. Then, another factor you have the diameter, because the avaiability of one or another solution depends on these 2 factors. A few years ago you only had internal restrainedjoints for smaller diameters, nowadays you have also internal restrained joints for bigger diameters (I believe untill 600 mm at least). The internal restrained joints are much more easier to install. For the external ones you have to weld the pipe at the bottom, and it gives more logistical problems. Neither the internal or external are easy to dimantle because you can't consider it as dismantling joints. If we are talking of automatic joints, it's almost impossible to dismantle. The mechanic joints, with externally fittings (but not restrained) you can dismantle if you wish in the future (but technically it isn't the best option.

To repair a ductile iron pipe there are several options, as for examplo the HERMETICA fittings produced in Spain.

Kind regards,

Marta Dutschmann Gomes