How to rename or change the filesystem label in a linux based device

Question

I am working on a linux OS based device and writing a script to mount the USB Most of my working devices are having Filesystem with "/dev/sdb1" and I could mount them to the USB using a script. (as below)

Filesystem                Size      Used Available Use% Mounted on
tmpfs                     1.0G     82.5M    987.3M   8% /tmp
tmpfs                     1.0G      8.0K      1.0G   0% /dev/shm
tmpfs                     1.0G         0      1.0G   0% /mnt
/dev/mmcblk0p2            5.4G     48.3M      5.1G   1% /mnt/ffs
/dev/mmcblk0p1          487.9M    432.0K    451.7M   0% /mnt/ffs/permanent
/dev/sda1               923.8G     23.9G    899.8G   3% /mnt/hd
/dev/sda2                 4.5G    261.3M      4.2G   6% /mnt/data
/dev/loop0               19.6G    407.8M     19.1G   2% /mnt/logstorage
/dev/loop0               19.6G    407.8M     19.1G   2% /log

But lately, I've noticed one of these devices got diff label as indicated below

~ # df -h
Filesystem                Size      Used Available Use% Mounted on
tmpfs                     1.0G     61.7M   1008.1M   6% /tmp
tmpfs                     1.0G      8.0K      1.0G   0% /dev/shm
tmpfs                     1.0G         0      1.0G   0% /mnt
/dev/mmcblk0p2            5.4G    210.7M      4.9G   4% /mnt/ffs
/dev/mmcblk0p1          487.9M    432.0K    451.7M   0% /mnt/ffs/permanent
**/dev/sdb1               923.8G     20.0G    903.8G   2% /mnt/hd**
**/dev/sdb2                 4.5G    219.2M      4.3G   5% /mnt/data**
/dev/loop0               19.6G    110.5M     19.4G   1% /mnt/logstorage
/dev/loop0               19.6G    110.5M     19.4G   1% /log

Is there any way to rename the file systems names to the prior stated (i.e. change or rename /dev/sdb1 and /dev/sdb2 to /dev/sda1 and /dev/sda2)?

I've tried checking /etc/fstab, but there is no such file in the device. What else I could do here? Please advise