Renewable seat ring threaded only or threaded seal welding

[rahulthakur]

Dear sir,

As per my client requirement. The renewable seat rings shall be threaded without seal welding.
My question is, whether better to use threaded seat ring followed by seal welding Or Either threaded in or seal welding only?? My understanding is threaded in with seal welding will be better.
Also please advice which standard defines design of renewable seat???

Find attached correspondence with API regarding seat ring from "google"

 

[valvit]

Per API, if you seal weld the ring, it is not a renewable seat. To be a renewable seat, it must be threaded or pressed in.

Valvit