Around/round the clock
Definition 1 of 1
Pro Tip 1/3Consistent Activity
Used to emphasize that an activity continues without stopping day and night. 
The factory has been running around the clock to meet the high demand.
Pro Tip 2/3Figurative Use
Not meant literally, but to emphasize urgency or dedication. 
Our team worked around the clock to get the website back online.
Pro Tip 3/3Time Sensitivity
Implies a response to time-sensitive situations or deadlines. 
Emergency services are available around the clock for urgent cases.