Characterizing Energy Consumption of the Injection Molding Process

Abstract

Presently available systems for sustainability assessment do not fully account for aspects related to a product’s manufacturing. In an effort to make more sustainable decisions, today’s industry seeks reliable methods to assess and compare sustainability for manufacturing. As part of the Sustainable Manufacturing program at the National Institute of Standards and Technology (NIST), one of our objectives is to help develop the needed measurement science, standards and methodologies to evaluate and improve sustainability of manufacturing processes. As a first step towards developing standard reference sustainability characterization methodologies for unit manufacturing processes, in this paper we focus on injection molding with energy as the sustainability indicator. We present a science-based guideline to characterize energy consumption for a part manufactured using the injection molding process. Based on the study, we discuss the selection of process parameters and manufacturing resources, determination of cycle time, theoretical minimum energy computations, and estimated energy computations for characterizing the injection molding process.

Development and utilization of a Process-oriented Information Model for sustainable manufacturing

“…For example, Weissman et al [3] estimated energy consumption by considering the power consumption of an injection molding machine and the cycle time of each activity to make a given part. Madan et al [4] proposed a quantitative measurement to determine the theoretical minimum energy consumption of each activity of the injection molding process. Powder metallurgy is another environmentally benign manufacturing process compared to other shaping processes because of its net-shape capabilities and its very high material-utilization factor [19].…”

“…The equations for calculating energy consumption are selected from Refs. [4,5]. Lookup tables can be further incorporated and implemented here, if the LCA data are desired.…”

“…Although different evaluation metrics have been developed to evaluate the sustainability performance of a variety of manufacturing processes [1][2][3][4][5], they are all developed in the context of a specific evaluation method and target at a certain manufacturing process. For example, both of Munoz et al [1] and Dahmus et al [2] analyzed the environmental impact of the machining processes, but the former used an analytical approach while the latter used a system-oriented approach.…”

Analysis and Optimization based on Reusable Knowledge Base of Process Performance Models

“…Consequently, the injection molding process consists of three major sub-processes: (1) Melting, Injecting, or filling, (2) Cooling, (3) Ejection and resetting. The resulting cycle time, can be formulated as according to [33][34][35]:…”

Energy-Efficient Enhancement for Viscoelastic Injection Rheomolding Using Hierarchy Orthogonal Optimization

“…The most common methods for forming plastic polymers include injection, compression, extrusion, coextrusion, blow, and blend molding. Injection-molded parts are widely used in consumer products and industrial equipment, the injection-molded components constitute 42% and 33% in toys and medical equipment components, respectively [1].…”