ISO 10767-2:1999 油圧作動油の出力—システムおよびコンポーネントで生成される圧力リップルレベルの決定—パート2：ポンプの簡略化された方法 | ページ 2

Foreword

ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.

International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 3.

Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote.

International Standard ISO 10767-2 was prepared by Technical Committee ISO/TC 131, Fluid power systems, Subcommittee SC 8, Product testing.

ISO 10767 consists of the following parts, under the general title Hydraulic fluid power — Determination of pressure ripple levels generated in systems and components:

• Part 1: Precision method for pumps
• Part 2: Simplified method for pumps
• Part 3: Method for motors

Annex A forms a normative part of this part of ISO 10767. Annexes B and C are for information only.

Introduction

In hydraulic fluid power systems, power is transmitted and controlled through a liquid under pressure within an enclosed circuit. Hydraulic pumps are devices which convert rotary mechanical power into fluid power. Pump flow has a large, steady component and a smaller, cyclical component superimposed upon it. It is this smaller, cyclical component of the pump flow that reacts with the fluid system of the pump and its circuit, that results in pressure ripple or fluid-borne noise. This fluid-borne noise can be transmitted through the liquid under pressure to other attached components and structures, and can result in unwanted noise and vibrations.

While the flow ripple is the cause of the pressure ripple, it is more difficult to measure. Therefore pressure ripple will be used in this procedure to characterize the fluid-borne noise generation potential of hydraulic fluid power pumps. Pressure ripple is a function of the pump design and the circuit in which it is measured. It is important, therefore, that the test circuit be controlled so as to provide uniform results when comparing the fluid-borne noise generation potential of different types of pumps. Pressure ripple determined in accordance with this part of ISO 10767 may be different to that measured in fluid power systems because of the high impedance of the test line.

1 Scope

This part of ISO 10767 specifies a procedure for measuring the fluid pressure ripple characteristics of hydraulic fluid power pumps with a maximum error of + 1 dB to − 3 B.

ISO 10767-1 can be used if pressure ripple measurements at lower pressure levels, lower frequencies, or at greater accuracy levels is required. This procedure covers a frequency and pressure range that has been found to excite many circuits to emit airborne noise that most concerns designers of hydraulic fluid power systems. It allows the pressure ripple data to be published with minimal calculations and processing of the measured data. This part of ISO 10767 promotes quieter fluid power systems by establishing a uniform procedure for measuring and reporting the fluid pressure ripple characteristics of hydraulic fluid power pumps. Annex B contains a tutorial explanation of the technical basis for this test procedure.

2 Normative references

The following normative documents contain provisions which, through reference in this text, constitute provisions of this part of ISO 10767. For dated references, subsequent amendments to, or revisions of, any of these publications do not apply. However, parties to agreements based on this part of ISO 10767 are encouraged to investigate the possibility of applying the most recent editions of the normative documents indicated below. For undated references, the latest edition of the normative document referred to applies. Members of ISO and IEC maintain registers of currently valid International Standards.

3 Terms and definitions

For the purposes of this part of ISO 10767, the fluid power terms and definitions given in ISO 5598, the acoustical terms and definitions given in ISO 10767-1 and the following apply.

Bibliography