GB/T 17774-2025Fans - Dimensions (English PDF)

Foreword

This document complies with the provisions of GB/T 1.1-2020 "Standardization Work Guidelines Part 1: Structure and Drafting Rules of Standardization Documents".

Drafting.

This document replaces GB/T 17774-1999 "Dimensions of Industrial Ventilation Fans". Compared with GB/T 17774-1999, except for structural adjustments and...

Aside from editorial changes, the main technical changes are as follows.

a) The applicable boundaries of the scope have been changed (see Chapter 1, Chapter 1 of the 1999 edition);

b) Terms, definitions, and symbols have been changed (see Chapter 3, Chapter 3 of the 1999 edition);

c) The characteristics of the mixed-flow fan have been changed (see Figure 3, Figure 3 in the 1999 edition);

d) The dimensions and dimension naming requirements have been changed (see Chapter 4, Chapter 4 of the 1999 edition).

This document is equivalent to ISO 13351:2024 "Dimensions of ventilation fans".

Please note that some content in this document may involve patents. The issuing organization of this document assumes no responsibility for identifying patents.

This document was proposed by the China Machinery Industry Federation.

This document is under the jurisdiction of the National Technical Committee on Standardization of Wind Turbines (SAC/TC187).

Introduction

This document uses the dimensions for round flanges and light-duty ventilators as specified in ISO 65801, while the dimensions for medium-duty ventilators are as specified in ISO 65801.

The dimensions for heavy-duty ventilators are given in Tables 3 and 4.While manufacturers are not required to select the flange dimensions specified in this document...

While it reduces the size of the space, it also provides the possibility of interchangeability, thus reducing the technical barriers to free trade.

In this document, all major dimensions are based on the rounded values of the "preferred" numbers given in ISO 497.

1) This document is obsolete and has been replaced by ISO 13351.

Ventilation fan size

1 Scope

This document specifies the dimensions of round and rectangular flanges for general-purpose ventilators, as well as the naming conventions for ventilator dimensions. This document is not applicable.

Crossflow fans or ventilation equipment for household or similar purposes.

For round flanges, this document presents three different flange series. the first is for light-weight shell thicknesses, the second and third are...

In particular, medium-sized and heavy-duty ventilators are typically used in marine vessels or heavy industries.

To avoid unduly restricting the design of the ventilation fan, this document only specifies the pitch circle diameter, number of holes, and hole diameter. Flange thickness and flange inner and outer diameters are also specified.

The path can be freely chosen within the scope of good engineering practices.

2 Normative references

The contents of the following documents, through normative references within the text, constitute essential provisions of this document. Dated citations are not included.

For references to documents, only the version corresponding to that date applies to this document; for undated references, the latest version (including all amendments) applies.

This document.

Note. GB/T 321-2005 Preferred Numbers and Preferred Number Systems (ISO 3:1973, IDT) Categories - Part 1: Vocabulary Categories - Part 2: Categories

3 Terms, Definitions and Symbols