The Use of Low-Cost Forging Hammers to Increase Blacksmith Productivity in Various Working Environments

Abstract

Blacksmithing is one of the micro-enterprises in Bali, Indonesia, where traditional tools such as hand hammers are still used to make iron-based home appliances and souvenirs. The process is typically divided into two general steps, which begin with smelting/heating the metal materials and continue with repeatedly forging the materials by using a hand hammer. This traditional forging method has proven to be inefficient, taking a relatively long time and increasing the blacksmith's fatigue and musculoskeletal complaints, resulting in highly inefficient production. Therefore, in order to improve the efficiency in the forging process, this study develops a low-cost forging machine that could reduce the fatigue and musculoskeletal complaints of the blacksmith while also increasing the production number. The sample of this study takes place in Gubug village, Tabanan district, Bali Indonesia which includes 30 blacksmiths with normal anthropometric measurement. For the experimental method, a one-shot case study was implemented with a pre and post-test design group. In addition, this study also used two set environmental conditions which are based on different control temperatures. The results demonstrate that 30 blacksmiths showed a decrease in workload based on the work pulse, from 120.76 ± 3.02 bpm (when using hand hammer) to 88.50 ± 2.43 bpm (after using the proposed machine) (p<0.05). In addition, this study also observed a decrease in subjective complaints based on fatigue scores from 43.10 ± 2.08 to 33.90 ± 3.21 (p <0.05). In terms of musculoskeletal complaints, when the blacksmith used conventional tools, the complaints were 42.74 ± 3.48, however, when the proposed machine was used, their complaints were reduced to 31.83 ± 3.06 (p <0.05). The result from this study shows that environmental conditions such as setting a lower temperature in the forging area also could reduce the blacksmith’s workload, fatigue, and musculoskeletal complaints even better by a significant margin (p<0.05) based on paired T-test. When measuring productivity with a traditional tool, the result is 0.0263 ± 0.0028; however, when using the proposed machine, the result increased to 0.0326 ± 0.0081 (p <0.05), in other words, utilizing the proposed forging machine could increase 23.9% of blacksmith productivity.