API PUMPS-1xAPI, 2xAPI Approach

API 610 allowable nozzle loads are to be complied using table 2 and if necessary by Appendix-F.
Sometimes pumps are ordered saying 2XAPI allowables.Can somebody clarify to what the pump vendor understands by this and what the pipe stress engineer is to comply.

In the case of 2xAPI pumps will the stress engineer be required to use Appendix-f or simply limit the individual nozzle loads to a max of 2 times the listed values in table-2.
What major features of the pump change if a standard API pump is reordered as 2xAPI pump?

For piping design, the individual nozzle loads on horizontal pumps may be up to 2 times the Table 2 allowable values only if the conditions f.1.2.1 through F1.2.3 in Appendix F are satisfied. The checks in Appendix F ensure that any displacement or casting distortion caused by loads greater than the Table 2 loads are within the vendors design criteria. Users should consult vendors when the loads are greater than 2 times the Table 2 allowable values.