A single PQR can support a single WPS or multiple WPSs. Likewise a single WPS may be supported by a single PQR or multiple PQRs.
Example: A preliminary WPS (the engineer's best guess of what will work) is developed defining a specific weld joint of a specific thickness, groove design, welding process, etc. A test weldment is welded while a test witness verifies the materials, process, groove details, etc. were in accordance with the preliminary WPS and the data and test results are recorded on the PQR.
Based on the acceptable results recorded on the PQR two WPSs for production are developed. One WPS, supported by the PQR, is developed for fillet welds, while a second WPS, still supported by the same PQR, is developed for grooved joints. The first WPS, for fillets, may be for unlimited bae metal thickness while the WPS for grooves is qualified for limited thickness.
Gotta run. I have a class to attend to.
Best regards - Al