BS ISO 3601-2:2016 pdf download.Fluid power systems – O-rings Part 2: Housing dimensions for general applications.
This part of ISO 3601 specifies the housing (gland) dimensions for class A 0-rings for general industrial applications conforming to ISO 3601-1, as well as housing dimensions for class B 0-rings used on selected metric-dimensioned hardware, e.g. fluid power cylinder bores and piston rods. These 0-rings are for use in general hydraulic and pneumatic applications without and with anti-extrusion rings (back-up rings). The dimensions of the 0-rings (di and d2), size codes (SC) and tolerances conform to
ISO 360 1-1.
Housing dimensions for the 0-rings intended for aerospace applications that are specified in ISO 3601-1 are addressed in Annex A.
NOTE I It is expected that 0-ring housing dimensions for special applications be agreed upon between the 0-ring manufacturer and the user.
NOTE 2 The terms housing”, “groove’ and “gland are interchangeable, and their usage is a matter of local convenience. In this part of Iso 3601. the term “housing” is used exclusively.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 3601-1:2012, Fluid power systems — 0-rings — Part 1: Inside diameters, cross-sections, tolerances and designation codes
ISO 3601-4, Fluid power systems — 0-rings — Part 4: Anti-extrusion rings (back-up rings)
ISO 5598, Fluid power systems and components — Vocabulary
ISO 8015, Geometrical product specifications (GPS) — Fundamentals — Concepts, principles and rules
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 5598 apply.
4 Symbols
For the purposes of this document, the following symbols are used in this part of ISO 3601.
50-ring housings
5.1 Typical 0-ring applications
5.1.1 Figure 1 shows a typical 0-ring as presented in ISO 3601-1.
5.1.2 Figure 2 shows the features of an 0-ring housing for use in dynamic rod and piston applications.
5.1.3 Figure 3 shows the features of 0-ring housings used in static rod and piston applications. It also shows an example of a face (axial) seal.
5.1.4 0-ring housings for face seal applications have different dimensional requirements depending upon whether the pressure is internal or external to the system. See Figure 4 for illustrations.
5.1.5 Figure 5 shows examples of widths of 0-ring housings for use with or without anti-extrusion rings (back up rings). Recommendations for the use of anti-extrusion rings are given in ISO 3601-4.
5.3.3 The latest International Standards for surface roughness measurement require new statements for roughness requirements. Because of the short measuring length, an exact roughness is not measurable. In these cases, a visual inspection using master parts is permitted.
5.4 Corners and edges of undefined shape
Values for inside corner edge, ) that depend on the cross-sections of housings and rods are specified in Table 1. Values for the undefined edge of the housing outside corner are specified in Figures 6 and 7.
5.5 Lead-in chamfer
5.5.1 A lead-in chamfer with an angle of 15° to 200 shall be used to prevent damage to the 0-ring by either the rod or the piston upon assembly into the cylinder bore. Chamfer edges shall be rounded. Figures 6 and 2 illustrate lead-in chamfers for piston and rod housings, respectively.
5.5.2 Values for the lengths of lead-in chamfers, dimension z, for the cross-sections of housings and rods are specified in Table 1.
5.6 Calculation of housing dimensions for radial sealing applications
5.6.1 General
For the basic dimensions of housings for 0-rings, see Tables 2 to S. Dimensions d3 (for piston sealing applications) and d6 (for rod sealing applications) and the depth of the housing apply if the percentage of effective 0-ring cross-sectional compression is within the limits given in Figure 8. depending on the application and 0-ring cross-section.
6 Requirements
6.1 Housing dimensions
6.1.1 Housings for piston sealing in hydraulic and pneumatic applications
6.1.1.1 The nominal 0-ring inside diameter, d1, should be stretched between 2 % and 5 % for dynamic applications and 2 % and 8 % for static applications. For 0-rings with a diameter d1 smaller than 20 mm, this is not always possible, which can result in a wider range of stretch. To minimize this range and the maximum stretch, it is necessary to minimize the tolerances of the housing diameter, d3. and have a less stringent requirement for the minimum 0-ring stretch.
In dynamic applications, it is important to keep the maximum stretch to 5 % or less to avoid detrimental effects on sealing performance.BS ISO 3601-2 pdf free download.