Adding Duplicate (Sort of Duplicate) Nozzle to Existing Vessel - Repair?

[AWDMIKE]

We are planning on installing a new nozzle in an existing vessel. The new nozzle will be a duplicate of an existing nozzle (for the most part - see below) and will be installed at the same elevation of that existing nozzle (i.e. same shell course). We are hoping to classify the addition of the new nozzle as a repair.

If we wish to classify the addition of the new nozzle as a repair, must the following criteria for the new nozzle be identical to existing nozzle?

1. Shell edge bevel?
2. Nozzle edge bevel?
3. Type of welding process used?
4. Specified minimum/maximum chemical composition?
5. Compliance of the new nozzle with a standard with which the existing nozzle did not comply (e.g. API 934-C).

Thanks for any help or guidance anyone can offer. We are using the NBIC for this work.

 

[metengr]

The requirements in Part 3 of the NBIC are very clear for repairs. An in-kind additional nozzle would be a repair and follow the code of construction requirements for attachment - you may have options for weld joint detail.

 

[racookpe1978]

To be clear, are you replacing an existing nozzle with one essentially the same shape and configuration in the same location, but with a (higher ??) specification or higher certification rating?

Or are you adding a new nozzle, similar to earlier nozzles, in a new location?

 

[AWDMIKE]

We are adding a new nozzle which will be the same size, same flange rating, same overall dimensions, and same reinforcement as an existing nozzle. The new nozzle is even at the same elevation as the existing nozzle and is in the same shell course.

Our concern is that the in addition to the weld joint detail that the duplicate nozzle may have to have the same chemical composition and physical properties as the existing nozzle, however, the new nozzle will be required to comply with API 934-C. Thinking about it a little bit more, API 934-C will impose more stringent requirements and I would hope that in the spirit of our Codes that would be even more desirable.

 

[david339933]

As Metengr stated, check out NBIC part III, it discusses chemical composition...."examples of repairs".