I am currently at level 77 smithing but I do not have the perk to create Orcish armor and weapons at forges, and improve them twice as much. However, I was able to improve a set of Orcish gauntlets to "exquisite" at a work bench with the Orcish Ingot (forget what its actually called). Am I supposed to be able to do this or is this some kind of glitch?

Twice as much means legendary I think. Example: If you have 91 Smithing, and don't have the Daedric perk, you can't make it Legendary. At least that's what I think.

As far as I know you dont need perks for improvements. Just a certain skill level.

You can improve all armors and weapons you find, provided you have the necessary materials.

However, if you don't take the associated perks in Smithing, you cannot create those armors yourself, and you will never improve them as much as you could compared to if you did take the associated perks.

The highest you can get is "Flawless" without the perk, and the only way to get it higher to "Legendary" without the perk is to either drink a potion that fortifies your Smithing skill, or else equip gear that fortifies your Smithing before you use the grindstone/workbench.

Yes, there are different Blacksmithing requirements for upgrading, depending on if that armor/weapon perk has been purchased.

Here are the Upgrade requirements for Blacksmithing (No Perk / Perk):

Fine (14 / 14)
Superior (31 / 22)
Exquisite (65 / 40)
Flawless (100 / 58)
Epic (150 / 74)
Legendary (196 / 91)