As described in the exporting and saving your results page, you can export up to 500 or 1000 records at a time from a Web of Science search, in various formats. If you are dealing with larger numbers of papers, it is possible to run several exports and join the files together afterwards.
It is also possible to export larger sets of papers (up to 50,000 records at a time) into InCites, which is a large-scale analysis tool built on top of Web of Science. There is guidance on the InCites page of the libguide on how to use this system. You can then download the dataset from within InCites, or analyse it further.
If you are doing more involved analysis, you can also access Web of Science data through their public API. An API (application programming interface) allows you to write code to query the database, for example to run a long series of automated queries without needing to search manually.
The UCL subscription allows us access to the "Web of Science Lite" API. This allows you to use the API to search and retrieve core article metadata.
To get access to the API, register on the Clarivate developer portal with your UCL email address, fill out the details of your planned project, and request access to the Lite API. This will be reviewed by Clarivate, who will then contact you directly with an API key.