The intention is to maximize the parts list and minimize consumable list.
What nonsense is this? If anything, the exact reverse should be true.

Clearly the ones doing the "intending" there are the hospital; and the "intention" is to get the contractor to fork out for as much as possible. I presume that's what you mean by the "parts list" - items for which the contactor bears the cost. Perhaps it would be simpler for the hospital just to list the items they are actually willing to pay for themselves (the "consumable list").

It sounds to me that the real problem there lies with the folk who administer the contracts! The issue you are describing is not one of definition of the words involved, but rather
who pays for each item.
But anyway, how
is the contractor paid (in general)? Surely some sort of authorization must be obtained before payments are released? Or do your folk just pay out against any old monthly (or quarterly
etc.) invoice? And what kind of contractor agrees to a situation where he has to bear the cost of any parts needed? Such an "all-inclusive" arrangement would be a risk that I can't imagine any astute businessman taking. I fear that (yet again) we are not being given the full picture here.

I see that in your second post you mention only two categories:- parts and consumables; no mention of disposable items. So I imagine that the Real Fight going on is who is to cover the cost of each - the hospital or the contractor. I must say that, if endless disputes are to be avoided, such matters are best threshed out, agreed and written down (together with appropriate examples if necessary)
before contracts are signed!
Consumable items are those that are
consumed (used up) during use; a dry-cell battery is an obvious example (but there again, so is a cheese sandwich) - they are then disposed of - that is, got rid* of. Also, how about cans of oil, service aerosols and the like? The contents are all consumed during use. Individually, such items are likely to be of relatively low value (in monetary terms).
As has already been mentioned, a disposable item is one that is used once, and then deliberately discarded - generally to avoid contamination. There are many such items used up in hospitals every day. However, there should not be too many such items in the biomeds' stores - just a few boxes of surgical gloves, maybe. Again, low cost.
The meaning of "parts" (especially
spare parts) should be obvious to anyone - even the most ardent bean counter. They are durable items, generally used to replace defective examples of the same thing when carrying out repairs and maintenance. If held on inventory (in the biomeds' stores, for example) they need to be properly accounted for (as their total value is likely to be considerable).
Good examples of all three categories have already been given by others in the above posts.

As we have seen, it could be argued that items such as SpO2 probes and BP cuffs could be considered to be
either consumable items
or replaceable "parts" - and there are many others, too (such as NIBP hoses and ECG leads - but what about trunk cables, and so on); but (as has already been mentioned) such distinctions should be made clear in contractual terms and condtions right form the beginning!
*
Unless, that is, you are required to "show used items" when an official visited; as was the case in Saudi MOH hospitals 25 years ago!