Advantages of the Rotational Molding Process 

The rotational molding process is the ideal manufacturing technology for many products in the underground distribution of electricity. The process and thermoplastic materials used by Thermodynamics have been time tested in the utility industry and have demonstrated outstanding performance, weatherability and durability for over thirty years.

Materials:

Polyethylene is available in a variety of grades - from low to high density. Density is a measure of specific gravity of a resin based on ASTM standards. Low density resins (range less than 0.925 g/cm³) are generally used whenever stiffness is not essential. On the other end of the scale, high density resins (range from 0.941 g/cm³ - 0.959 g/cm³) offer increased stiffness but reduced toughness or impact. Wall thickness is determined by the amount of material used to charge the mold and can be modified by adjusting the amount of material.

The linear polyethylene resins selected by Thermodynamics offer excellent cold temperature impact strength, ultra violet light resistance, compatibility with most commercial cleaning chemicals, a durable surface finish and outer wall that resists denting and cracking from normal wear and tear. Thermodynamics products have been field tested and are suitable for operating temperatures ranging from - 60º F to over 140º F.

Design:

All Thermodynamics utility products combine elements of design, material and process based on computer modeling and detailed finite element analysis (FEA) of structure and stress. After initial computer models establish the product design concept, detailed analyses optimize design, material formulation and wall thickness unique for each product. Extensive field testing validates product rigidity, toughness and strength for each application.

Process:

The rotational molding process allows flexibility in part design, material selection and manufacturing. The process is unique in that parts are formed hollow and seamless. Considered low pressure, unlike other plastics processes such as injection or structural foam molding. Parts formed from linear polyethylene in the rotational process are molded stress free which improves impact resistance and long term durability. Through advanced processing techniques Thermodynamics is able to increase material thickness in critical high impact areas and wear surfaces to optimize the weight to material cost ratio.

The resulting Thermodynamics’ products exceed application requirements.