Morphine sulfate is one of many opioid medications prescribed for moderate to severe chronic pain and can be quite effective. There is no "normal" daily dosage. If you are not currently taking any opioids, the doctor will probably start you on a lower dosage to see how you do and gradually increase it. It can be dangerous to start with too high a dosage of any opioid.
Everyone is different, so which opioid would be most effective and at what dosage is something you and your doctor will have to determine together. It may take some trial and error to find what works best for you.
I have had fibromyalgia for over 5 years and I'm on 30 mg morphine (ms contin) twice a day, it works pretty well, I have to take loratab as a breakthrough though.