With an understanding that keeping the accumulator insulation in tack will look nice and OE, but it is for condensation. As refrigerant is pumped thru the condenser, you have a high pressure liquid with a reduced temperature. It pass thru an oriface tube the has no control on the amount of refrigerant that floods into the evaporator. Going from a high pressure to a low pressure, then adding heat from the fan blowing warm cabin air across it, will cause the refrigerant to boil. It boils at a low temperature where in the best case, all of it turns to a gas. But liquid still remains under certain circumstances and makes it way into the accumulator. This liquid & gas hits a plastic inverted cones and falls onto the drying agent, with some oil. The accumulator sweats and drips water on the outside, but it's main function is to allow liquid refrigerant t boil off into a gas before it can reach the suction line fitting, then to the compressor. Liquid can't be compressed so an over-filled system can cause compressor damage. So the accumulator is a dryer, reservoir for oil and room for boiling off liquid into a gas. The insulation does not effect the systems performance, just keeps water from dripping onto the exhaust causing steam. Otherwise, it looks good.
Systems that use a thermal expansion valve controls the flow and uses a receiver/dryer...but is used on rear A/C because it is more efficient to boil off refrigerant even with low flow.