Insulating joints come preassembled and pretested versus the traditional insulating flange kit, which requires a skilled technician to assemble it on site. By using the Insulating joint the company saves on site labor. Insulating joints are also less likely to fail from improper installation which could render a Cathodic Protection system ineffective and likely result in both internal and external corrosion.
With an insulating joint, serviceability and maintenance is simplified. Whereas, when using an insulating flange kit the system may become shorted when buried (from settling, thermal expansion or over-tightening). In this case, the cost to repair a damaged or leaking system significantly exceeds the initial investment of an insulating joint. It is also more likely that the pipeline would have to be shut down if maintenance or replacement is required.
When evaluating the advantages and disadvantages of using insulated flange kits versus insulating joints it would seem that when life cycle costs are considered, the use of insulting joints is advantageous over the flange kits.