GB/T 4450-2008 in English

《GB/T 4450-2008船用盲板钢法兰》由TC137（全国船用机械标准化技术委员会）归口，主管部门为国家标准化管理委员会。
本标准规定了法兰连接尺寸按GB/T569和GB/T2501的船用盲板钢法兰的分类、要求、试验方法、检验规则、标志、包装和贮存。本标准适用于公称压力不大于１．６ＭＰａ，介质为空气、海水、淡水、油和工作温度不高于３００℃的蒸汽的盲板法兰的设计、制造和验收。 本标准代替ＧＢ／Ｔ４４５０―１９９５《船用盲板钢法兰》。
本标准与ＧＢ／Ｔ４４５０―１９９５相比，主要有下列变化：
―――取消了ＡＳ型、ＢＳ型的ＤＮ１０ｍｍ 规格；
―――扩大了公称通径规格，ＤＮ 从５００ｍｍ 扩大到１０００ｍｍ；
―――Ａ 型、ＡＳ型ＤＮ３００ｍｍ 以上加钻一个螺孔；
―――修改了Ｂ型、ＢＳ型的结构和尺寸。

Marine blank steel flanges

1 Scope

This standard specifies the classification, requirements, test methods and inspection rules, as well as the marking, packaging and storage of marine blank steel flanges (hereinafter referred to as “blank flanges”) with the connection dimensions meeting those specified in GB/T 569 and GB/T 2501.

This standard is applicable to the design, manufacturing and acceptance of blank flanges whose nominal pressure is no greater than 1.6MPa and whose media are air, seawater, freshwater and oil as well as steam with a working temperature not exceeding 300℃.

2 Normative references

The following normative documents contain provisions which, through reference in this standard, constitute provisions of this standard. For dated references, subsequent amendments (excluding corrections), or revisions, of any of these publications do not apply to this standard. However, parties to agreements based on this standard 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 applies.

GB/T 569 Marine pipe flanges - Connection dimensions and mating face
GB/T 700-2006 Carbon structural steels
GB 712-2000 Hull structural steel
GB/T 1184-1996 Geometrical tolerancing - Geometrical tolerance for features without individual tolerance indications (eqv ISO 2768-2:1989)
GB/T 1958 Geometrical product specifications (GPS) - Geometrical tolerance - Verification
GB/T 2501 Marine pipe flanges - Connection dimensions and mating face

Foreword i
1 Scope
2 Normative references
3 Classification
4 Requirements
5 Test methods
6 Inspection rules
7 Marking, packaging and storage