Oilers/Plant Tenders (HHC) Civil Service Exam 2026 – 400 Free Practice Questions to Pass the Exam

The wick in a gravity oil feed system is typically made of worsted yarn. This material is chosen due to its unique properties, which make it particularly effective for this application. Worsted yarn is tightly spun, providing durability and a good capillary action necessary for drawing oil from the reservoir to the burner. Its structure allows for optimal absorption and release of oil, ensuring a steady flow as needed in various heating systems. Cotton, while absorbent, does not have the same strength and durability characteristics as worsted yarn, making it less effective for long-term use in high-temperature environments. Polyester and silk, although they may have some useful properties, generally do not provide the same level of performance in terms of heat resistance and oil retention as worsted yarn.