Devi Engineering Interview Questions and Answers

The ratio of PU Foam refers to the ratio of the two main components used in the production of polyurethane foam.

• The ratio typically consists of two main components: polyol and isocyanate.

• The ratio can vary depending on the specific type of PU foam being produced.

• For example, a common ratio for rigid PU foam is 1:1, while for flexible PU foam it can be 2:1 or 3:1.

The density of PU foam typically ranges from 10-50 kg/m^3 depending on the specific formulation and application.

• PU foam density can vary based on the specific formulation and application

• Typical density range is 10-50 kg/m^3

• Higher density foams are often used for structural applications while lower density foams are used for insulation

The resin in PU foam is polyol.

• Polyol is a key component in the production of polyurethane foam.

• It reacts with isocyanates to form the foam structure.

• Different types of polyols can be used to achieve specific foam properties.

• Common examples of polyols used in PU foam production include polyester polyols and polyether polyols.

The hardener in PU foam is a substance that reacts with the polyol component to initiate the polymerization process.

• The hardener is typically an isocyanate compound, such as MDI (methylene diphenyl diisocyanate) or TDI (toluene diisocyanate).

• The hardener reacts with the polyol component to form a polyurethane network, leading to the formation of the foam.

• The ratio of hardener to polyol is crucial in determining the pro...read more

Pop mixing ratio refers to the ratio of the amount of pop (soda) to other ingredients in a mixed drink.

• Pop mixing ratio is commonly used in cocktail recipes to specify the amount of soda to be added.

• For example, a popular pop mixing ratio for a rum and coke is 2 parts cola to 1 part rum.

• Adjusting the pop mixing ratio can alter the taste and strength of the drink.