Introduction:
Pressure die casting is a popular manufacturing process used to produce high-quality, complex metal components with excellent surface finishes. However, like any other manufacturing process, it has certain limitations. Among these limitations, the option 'C' - low scale production, is not counted as one of them. Let's discuss the other limitations of pressure die casting in detail.

Limitations of Pressure Die Casting:
1. Only small parts can be produced: One of the limitations of pressure die casting is that it is not suitable for producing large-sized components. This is because the size of the die casting machine limits the maximum size of the part that can be produced.

2. High cost: Pressure die casting involves the use of complex machinery, precision molds, and specialized equipment. The initial setup cost for die casting is high, making it less economical for small production runs. Additionally, the cost of designing and manufacturing the precision molds can be expensive.

3. Castings are porous: Porosity is another limitation of pressure die casting. During the casting process, air and gas can get trapped in the molten metal, resulting in the formation of pores or voids in the final casting. This can affect the mechanical properties and structural integrity of the component.

4. Limited material selection: Pressure die casting is most commonly used for non-ferrous metals such as aluminum, magnesium, and zinc. The process is not suitable for all types of metals and alloys. For example, high melting point materials like steel are not commonly used in pressure die casting due to the limitations of the process.

5. Part complexity: While pressure die casting is capable of producing intricate shapes and complex geometries, there are limitations to the level of complexity that can be achieved. Parts with thin walls, complex internal features, or undercuts may require additional machining or secondary operations to achieve the desired shape, adding to the overall cost and production time.

Conclusion:
In conclusion, pressure die casting has several limitations, including the inability to produce large parts, high setup costs, porosity in castings, limited material selection, and limitations in part complexity. However, low scale production is not one of the counted limitations of pressure die casting.