CWM enjoyed monopoly in recoveries for a long time. It is indeed a good custom recovery. Being the first custom recovery it really did lay good groundwork for everyone. It has helped countless users to flash/backup/restore their phones. But it has a major drawback that you have to use the volume rockers to control it. CWM did come up with touch based recovery but it is available to a very limited number of devices(Xperia ray not being one of them). So always using the physical buttons becomes kind of annoying. However thomas1991_12 at XDA developers has successfully ported TWRP recovery to Xperia Ray(ST18i).
This is a tutorial to flash CWM based recovery into your Xperia series device with a locked bootloader. Technically, you don’t actually flash in this process; its a much easier method unique only to Xperia devices.
For this you need to have a Rooted device!