"It can be very difficult sometimes for players to arrive in a foreign country and adapt quickly," Rangel told Swansea's official website.
"It's a totally different country and the style of football can take some time to get used to. But I think Michu, Chico and Pablo have settled in very quickly."
Rangel was especially enthusiastic about forward Michu's performance for Swansea.
"Michu has already scored six goals this season, which is brilliant considering he's only played in eight games," he said.
"He scored 15 goals in La Liga last season and showed his quality. I think he can do the same for us in the Premier League.
"You have already seen that he can score all types of goals and he wants to help the team defensively as well. So he has been a great buy for us."
Rangel joined Swansea from Terrassa in 2007.