Page 24 - 《橡塑技术与装备》英文版2025年12月

HINA R&P TECHNOLOGY AND EQUIPMENT

Design of 235/45 R18 electric car tire

Song Qian, Du Shuai, Li Xiaoming, Feng Tingting
(Shaanxi Yanchang Petroleum Group Rubber Co. LTD., Xianyang 712000, Shaanxi, China)

Abstract: In response to the special requirements of electric car tires, we have independently developed
a 235/45R18 tire. The main parameters of the tire's structural design are as follows: outer diameter of 662 mm,
section width of 253 mm, tread width of 194 mm, tread camber height of 7.8 mm, bead contact diameter of
460.7 mm, section horizontal axis position (H 1 /H 2 ) of 0.952473, tread pattern featuring asymmetric tread pattern,
utilizing a five-pitch design, with a total of 41 composite pitches, and a tread pattern depth of 7.2 mm. In terms of
construction design: the upper layer of the tread adopts highly wear-resistant and low rolling resistance tread
rubber, while the lower layer adopts low heat generation transition rubber; the belt layer uses two layers of
4×0.225UT high-strength steel cord with a cord density of 79 EPD. The manufacturing process employs a one-
step building machine and a hydraulic hot plate curing press. The performance test results of the finished
tires show that their key indicators, including outer edge dimensions, strength, bead unseating resistance,
durability, high-speed performance, and rolling resistance, all meet or exceed national and corporate
standards.
Key words: electric car tires; structural design; construction design
Classification number: TQ336.1 Article number: 1009-797X (2025)12-0018-05
Document code: B DOI: 10.13520/j.cnki.rpte.2025.12.005

The wave of electrification is profoundly reshaping performance verification of the finished product.
the global automotive industry landscape. As the world's
largest electric vehicle market, China, driven by both national 1 Technical requirements and design
new energy policies and robust market demand, has not objectives
only facilitated the rapid development of complete vehicle The product design complies with the requirements
manufacturing but also posed new technical requirements of GB/T 2978—2024 "Passenger Car Tyres-Specification,
and market challenges to the tire industry. The demand Dimensions, Inflation Pressure and Load Capacity".
for tires from automakers is shifting from the commonly Additionally, based on the experience accumulated by our
used specifications of traditional fuel vehicles to specific company in designing similar products and the market demand
specifications to meet the needs of lightweighting, energy for this specification of product, we propose design objectives,
conservation, and cost reduction. as detailed in Table 1:
In response to this trend, our company has selected
the mainstream specification of 235/45R18 for independent 2 Structural design
research and development, targeting the specific application 2.1 Outer diameter D and cross-sectional
scenarios of electric cars. This article will provide a detailed width B
introduction to the entire development process of this tire,
from establishing technical objectives, conducting structural Biography: Song Qian (1989-), holds a master's degree and works as an
engineer, primarily engaging in fundamental research on tire structure
design, formulating construction plans, to finally completing design and technological management.

51，No.12
·18·
·18· Vol.51 卷 第 12 期
第