GB/T 20462.1-2025Thermoplastic tubing and hoses for automotive use - Part 1: Non-fuel applications (English PDF)

Foreword

This document was drafted in accordance with the rules provided in GB/T 1.1-2020 Directives

for Standardization - Part 1.Rules for the Structure and Drafting of Standardizing Documents.

This document is Part 1 of GB/T 20462 Thermoplastic Tubing and Hoses for Automotive Use.

GB/T 20462 has issued the following parts.

---Part 1.Non-fuel Applications;

---Part 2.Petroleum-based-fuel Applications.

This document serves as a replacement for GB/T 20462.1-2006 Thermoplastic Tubing and

Hoses for Automotive Use - Part 1.Non-fuel Applications. In comparison with GB/T 20462.1-

2006, apart from structural adjustments and editorial modifications, the main technical changes

are as follows.

---The descriptions of nominal inner diameter and type in Scope are deleted (see Chapter

1 of Version 2006);

---Terms and definitions are added (see Chapter 3);

---Hoses of eleven nominal inner diameter specifications are added (see Chapter 5);

---The list of test items for various types of thermoplastic tubing and hoses is deleted (see

Table 2 of Version 2006);

---The requirements for verification pressure are added, with a holding time of 60 seconds

[see b) of Chapter 6];

---A new test fuel for resistance to surface fuel contamination is added, and one test fuel is

deleted [see f) of Chapter 6; e) of Version 2006];

---The test method for internal cleanliness is modified [see Appendix C, m) of Chapter 5

in Version 2006];

---The requirements for inspection frequency are added (see Chapter 7, Appendix D and

Appendix E).

This document modifies and adopts ISO 13775-1.2021 Thermoplastic Tubing and Hoses for

Automotive Use - Part 1.Non-fuel Applications.

The technical differences between this document and ISO 13775-1.2021 and the causes for

these differences are as follows.

---Hoses of eleven nominal inner diameter specifications are added (see Chapter 5), along

with their requirements. The hoses of eleven nominal inner diameter specifications are

Thermoplastic Tubing and Hoses for Automotive Use - Part

1 Non-fuel Applications

WARNING---personnel using this document shall have practical experience working in a

formal laboratory. This document does not address all potential safety issues. Users are

responsible for taking appropriate health and safety precautions and ensuring compliance

with relevant national laws and regulations.

1 Scope

This document specifies the requirements for extruded thermoplastic tubing and hoses used for

automotive vehicles, excluding air braking systems (see ISO 7628), fuel pipelines (see ISO

13775-2), and high-pressure hydraulic systems, and describes the corresponding test methods.

This document is mainly applicable to original equipment manufacturers (OEMs).

2 Normative References

The contents of the following documents constitute indispensable clauses of this document

through the normative references in the text. In terms of references with a specified date, only

versions with a specified date are applicable to this document. In terms of references without a

specified date, the latest version (including all the modifications) is applicable to this document.

ISO 188 Rubber, Vulcanized or Thermoplastic - Accelerated Ageing and Heat Resistance Tests

NOTE. GB/T 3512-2014 Rubber, Vulcanized or Thermoplastic - Accelerated Ageing and Heat

Resistance Tests - Air-oven Method (ISO 188.2011, IDT)

ISO 1402 Rubber and Plastics Hoses and Hose Assemblies - Hydrostatic Testing

NOTE. GB/T 5563-2025 Rubber and Plastics Hoses and Hose Assemblies - Hydrostatic Testing

(ISO 1402.2021, IDT)

ISO 1817.2024 Rubber, Vulcanized or Thermoplastic - Determination of the Effect of Liquids

NOTE. GB/T 1690-2010 Rubber, Vulcanized or Thermoplastic - Determination of the Effect of

Liquids (ISO 1817.2005, MOD)

ISO 3795 Road Vehicles, and Tractors and Machinery for Agriculture and Forestry -

Determination of Burning Behavior of Interior Materials

NOTE. GB/T 20953-2007 Tractors and Machinery for Agriculture and Forestry - Determination of

Burning Behavior of Cab Interior Materials (ISO 3795.1989, MOD)

3 Terms and Definitions

The terms and definitions defined in ISO 8330 are applicable to this document.

4 Classification and Materials

Thermoplastic tubing and hoses shall be constructed of extruded thermoplastic material with or

without an integral reinforcing layer. They may also have an inner liner to improve liquid

resistance and/or heat resistance, and an extruded outer coating to improve environmental

and/or flame retardancy. The outer coating does not necessarily need to be bonded to the

thermoplastic tubing or hoses. In accordance with the application, thermoplastic tubing and

hoses can be classified into the following four types.

---Type 1.vacuum and electrically controlled thermoplastic tubing or hoses;

----Type 2.thermoplastic tubing or hoses of cooling systems;

----Type 3.thermoplastic tubing or hoses of windshield/headlight cleaning systems;

---Type 4.thermoplastic tubing or hoses of exhaust gas circulation systems.

5 Dimensions

The nominal inner diameter, inner diameter and tolerances, and minimum wall thickness of

thermoplastic tubing or hoses shall conform to the specifications in Table 1.

The wall thickness shall be the sum of the individual wall thicknesses of each component

constituting the structure of the thermoplastic tubing or hoses. The wall thickness of each

component shall enable each component to perform its own function and the function of the

thermoplastic tubing or hoses as a whole.

6 Requirements

The following tests shall be selected for each application of thermoplastic tubing or hoses, based

on the performance requirements of the finished products. All tests shall be conducted without

an adhesive protective layer.

a) Burst pressure. when tested in accordance with ISO 1402, the minimum burst pressure

for hoses of various structures with a nominal inner diameter <= 14 shall be 2 MPa,

and the minimum burst pressure for hoses of various structures with a nominal inner

diameter > 14 shall be 1.5 MPa.

b) Verification pressure. when tested in accordance with ISO 1402, the verification

pressure for hoses of various structures shall be 1 MPa, with a holding time of 60

seconds.

c) Low-temperature impact performance. after a low-temperature impact test at -40 °C

as specified in 9.3 of ISO 7628.2010, hoses of various structures shall show no

the adhesive strength between each adhesive layer shall not be less than 1.5 kN/m.

m) Flammability. when tested in accordance with ISO 3795, the burning rate of hoses of

various structures shall not exceed 100 mm/min.

n) Internal cleanliness. when tested in accordance with Appendix C, insoluble impurities

shall not exceed 5 g/m².

o) Resistance to windshield washer fluid. when injected with a mixture of 50% by

volume water and 50% by volume isopropanol and aged for 1,000 hours at the

temperature selected in d) of the 1,000-hour heat ageing resistance test, hoses of

various structures shall meet the low-temperature impact resistance requirements of

c) and, where applicable, the adhesive strength requirements of l).

p) Contamination of painted surfaces due to substance extraction by windshield washer

fluid. when tested in accordance with Method B of ISO 3865.2020, using the

windshield washer fluid described in o) instead of distilled water, there shall be no

contamination on painted metal surfaces.

q) Resistance. when tested in accordance with 4.5 ~ 4.7 of ISO 8031.2020, the resistance

shall be >= 10 Mohm.

r) Bending resistance. when tested in accordance with ISO 10619-1, the minimum

deformation coefficient (T/D) shall be >= 0.7.

For thermoplastic tubing or hoses with a nominal inner diameter less than 10 mm, the

mandrel diameter shall be 140 mm; for thermoplastic tubing or hoses with a nominal

inner diameter of 10 mm and a nominal inner diameter less than or equal to 12 mm,

the mandrel diameter shall be 220 mm; for thermoplastic tubing or hoses with a

nominal inner diameter > 12 mm, the mandrel diameter shall be 300 mm.

s) Resistance to internal pressure drop. when tested in accordance with ISO 7233 at an

absolute pressure of 0.03 MPa and 100 °C, the flattening of the thermoplastic tubing

or hoses after 10 minutes shall not exceed 50%.

7 Inspection Frequency

Type inspection is conducted to confirm that the manufacturing method and hose design

conform to all material, structural, and test requirements of this document. Type inspection shall

be repeated at least every 5 years, or when the manufacturing method or materials change.

Routine inspection refers to the inspection performed on all hoses and hose assemblies prior to

shipment.

Type inspection and routine inspection are respectively specified in Appendix D and Appendix

E.

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