USING STATISTICAL PROCESS CONTROL AND SIX SIGMA TO CRITICALLY ANALYSE SAFETY OF HELICAL SPRINGS: A RAILWAY CASE STUDY

The paper exhibits the examination of life quality evaluation of helical coil springs in the railway industry as it impacts the safety of the transportation of goods and people. The types of spring considered are: the external spring, internal spring and stabiliser spring. Statistical process control was utilised as the fundamental instrument in the investigation. Measurements were performed using a measuring tape, dynamic actuators and the vernier caliper. The purpose of this research was to examine the usability of old helical springs found in a railway environment. The goal of the experiment was to obtain factual statistical information to determine the life quality of the helical springs used in the railroad transportation environment. Six sigma advocacies were additionally used as a part of this paper. According to six sigma estimation examination only the stabilizers and inner springs for coil bar diameter met the six sigma prerequisites. It is reasoned that the coil springs should be replaced as they do not meet the six sigma requirements.