A user may have different environments with different rate limits (e.g., not more than 45 requests in a minute). Also, there may be a requirement to devise a solution where process flow should get delayed instead of aborting after rate limit has exhausted.
To achieve this, following method should be used to implement the rate limit in a process flow.
Add an error intermediate event on the Webservice consumer activity. In the error intermediate path, check if the error messages are due to exhausted rate limit (attached ppt has the documented steps for getting an error message from the aborted activity).
If the exception thrown is due to rate limit exhaustion, then add the appropriate delay and rerun the Consumer activity. Following is the screen shot with an example of provided solution. Also, attached is the sample process flow with similar solution.