GB/T 14905-2020Rubber and plastics hoses. Determination of adhesion between components (English PDF)

Foreword

This Standard was drafted in accordance with the rules in GB/T 1.1-2009.

This Standard serves as a replacement of GB/T 14905-2009 Rubber and Plastics

Hoses - Determination of Adhesion between Components. In comparison with GB/T

14905-2009, the main technical changes are as follows.

---The Chapter "Terms and Definitions" is added (see Chapter 3);

---The scope of application of Type 7 test piece is expanded; it is applicable to

hoses whose spacing between adjacent coils of the helix is greater than 10 mm,

and also suggestions for the preparation of test pieces when the spacing

between adjacent coils of the helix is less than 10 mm are provided (see 6.3.8;

1 Scope

Adequate adhesion between components of a hose is the basis for the hose to perform

well during use. This Standard specifies methods for the determination of the adhesion

between lining and reinforcement, between cover and reinforcement, between

reinforcement layers, between cover and outer lamination (thin layer of material

outside the cover for protection) and between lining and inner lamination (thin layer of

material inside the lining to reduce permeation of fluid into the lining).

2 Normative References

The following documents are indispensable to the application of this document. 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 5893 Rubber and Plastics Test Equipment - Tensile, Flexural and Compression

Types (constant rate of traverse) - Specification

3 Terms and Definitions

For the purposes of this document, the terms and definitions given in ISO 8330 apply.

ISO and IEC maintain terminological databases for use in standardization at the

following addresses.

4 Principle

Using test pieces of standard dimensions, the adhesion strength between lining and

reinforcement, between cover and reinforcement, between reinforcement layers,

between cover and outer lamination and between lining and inner lamination is

measured under specified conditions.

5 Apparatus

The machine shall be power driven, equipped with a suitable dynamometer, capable

of maintaining a substantially constant rate of traverse of the moving head during the

test and fitted with an autographic recorder. It shall comply with the requirements for

class 0.5 or 1 of ISO 5893.

For testing ring test pieces (type 6 and type 8), a mandrel shall be provided that is a

close sliding fit in the test piece. This mandrel shall be capable of being fitted into the

driven head of the machine so that it will rotate freely during the test.

6 Test Pieces

Strip, cut from the hose as a 35 mm +/- 2 mm wide ring which is then cut transversely

to form a strip.

Strip, cut along a reinforcing helix, 25 mm +/- 0.5 mm wide or the maximum obtainable.

7 Procedure

The rate of travel of the power-driven grip shall be such as to provide a rate of ply

separation of 50 mm/min +/- 5 mm/min (for test pieces of types 1 to 7) or 25 mm/min +/-

8 Expression of Results

The trace obtained from the graphical recorder shows the variations in the force at

which the plies or layers have separated.

9 Test Report

The test report shall contain the following information.

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