This standard is drafted in accordance with the rules given in GB/T 1.1-2009.
This standard replaces GB/T 1048-2005 Pipework components - Definition and selection of PN. In addition to editorial changes, the following main technical changes have been made with respect to GB/T 1048-2005:
——The definition of nominal pressure designated by Class is added (see Clause 2);
——The nominal pressure PN 160, PN 250, PN 320 and PN 400 are added (see Table 1);
——PN 20, PN 50, PN 110, PN 150, PN 260 and PN 420 are deleted and replaced with Class 150, Class 300, Class 600, Class 900 and Class 1500 (see Table 1; Clause 3 of Edition 2005);
——The preferred values of Class designated are added (see Table 1).
This standard is redrafted by reference to but is not equivalent to ISO 7268:1983 Pipe components - Definition of nominal pressure.
This standard was proposed by the China Machinery Industry Federation.
This standard is under the jurisdiction of SAC/TC 237 National Technical Committee on Pipeline Fittings of Standardization Administration of China.
The previous editions of this standard are as follows:
——GB/T 1048-1970, GB/T 1048-1990 and GB/T 1048-2005.
Pipework components - Definition and selection of nominal pressure
1 Scope
This standard gives the definition of nominal pressure when applied to components of a pipework system, and states the nominal pressure series for use with these same components.
This standard is applicable to piping components whose nominal pressure is designated by PN or Class.
2 Terms and definitions
For the purposes of this standard, the following terms and definitions apply.
2.1
nominal pressure
an alphanumeric designation related to the mechanical properties and dimensional characteristics of components of a pipework system, which comprises the letters PN or Class followed by a dimensionless number
Note 1: The dimensionless number does not represent a measurable value and shall not be used for calculation purposes except where specified in the relevant standard.
Note 2: The letters PN or Class have no meaning except in relation to the relevant standards of pipework components.
Note 3: The maximum permissible working pressure of pipework components depends on PN or Class, material, design and maximum permissible working temperature of pipework components.
Note 4: The pipework components designated by the same PN or Class and DN numbers shall have the same connection dimensions as the flanges to which they are fitted.
3 Nominal pressure series and selection
The nominal pressure are designated by PN or Class. Nominal pressure values shall be selected from Table 1.
Foreword I
1 Scope
2 Terms and definitions
3 Nominal pressure series and selection
ICS 23.040.60
J 15
GB
中華人民共和國國家標(biāo)準(zhǔn)
GB/T 1048—2019
代替GB/T 1048—2005
管道元件 公稱壓力的定義和選用
Pipework components—Definition and selection of nominal pressure
(ISO 7268:1983,Pipe components—Definition of nominal pressure,NEQ)
2019-05-10發(fā)布 2019-12-01實施
國家市場監(jiān)督管理總局
中國國家標(biāo)準(zhǔn)化管理委員會 發(fā)布
前言
本標(biāo)準(zhǔn)按照GB/T 1.1—2009給出的規(guī)則起草。
本標(biāo)準(zhǔn)代替GB/T 1048—2005《管道元件 PN(公稱壓力)的定義和選用》。本標(biāo)準(zhǔn)與GB/T 1048—2005相比,除編輯性修改外主要技術(shù)變化如下:
——增加了用Class標(biāo)識的公稱壓力的定義(見第2章);
——增加了公稱壓力數(shù)值PN 160、PN 250、PN 320和PN 400(見表1);
——刪除了PN 20、PN 50、PN 110、PN 150、PN 260和PN 420,用Class 150、Class 300、Class 600、Class 900和Class 1500代替(見表1,2005年版的第3章);
——增加了Class系列優(yōu)選的數(shù)值(見表1)。
本標(biāo)準(zhǔn)使用重新起草法參考ISO 7268:1983《管道元件 公稱壓力的定義》編制,與ISO 7268:1983的一致性程度為非等效。
本標(biāo)準(zhǔn)由中國機械工業(yè)聯(lián)合會提出。
本標(biāo)準(zhǔn)由全國管路附件標(biāo)準(zhǔn)化技術(shù)委員會(SAC/TC 237)歸口。
本標(biāo)準(zhǔn)所代替標(biāo)準(zhǔn)的歷次版本發(fā)布情況為:
——GB/T 1048—1970、GB/T 1048—1990、GB/T 1048—2005。
管道元件 公稱壓力的定義和選用
1 范圍
本標(biāo)準(zhǔn)給出了管道系統(tǒng)元件公稱壓力的定義,并規(guī)定了管道元件使用的公稱壓力系列。
本標(biāo)準(zhǔn)適用于公稱壓力用PN或Class標(biāo)識的管道元件。
2 術(shù)語和定義
下列術(shù)語和定義適用于本文件。
2.1
公稱壓力 nominal pressure
與管道系統(tǒng)元件的力學(xué)性能和尺寸特性相關(guān)的字母和數(shù)字組合的標(biāo)識,由字母PN或Class和后跟的無量綱數(shù)字組成。
注1:除相關(guān)標(biāo)準(zhǔn)中另有規(guī)定外,無量綱數(shù)字不代表測量值,也不應(yīng)用于計算。
注2:除與相關(guān)的管道元件標(biāo)準(zhǔn)有關(guān)聯(lián)外,字母PN或Class不具有意義。
注3:管道元件的最大允許工作壓力取決于管道元件的PN數(shù)值或Class數(shù)值、材料、元件設(shè)計和最高允許工作溫度等。
注4:具有相同PN或Class和DN數(shù)值的管道元件,同與其相配合的法蘭具有相同的連接尺寸。
3 公稱壓力系列及選用
公稱壓力包括PN和Class兩個系列,公稱壓力數(shù)值應(yīng)從表1中選取。
表1 公稱壓力數(shù)值
PN 系列 Class 系列
PN 2.5 Class 25a
PN 6 Class 75
PN 10 Class 125b
PN 16 Class 150
PN 25 Class 250b
PN 40 Class 300
PN 63 (Class 400)
PN 100 Class 600
PN 160 Class 800c
PN 250 Class 900
PN 320 Class 1500
PN 400 Class 2000d
— Class 2500
— Class 3000e
— Class 4500f
— Class 6000e
— Class 9000g
注:帶括號的公稱壓力數(shù)值不推薦使用。
a 適用于灰鑄鐵法蘭和法蘭管件。
b 適用于鑄鐵法蘭、法蘭管件和螺紋管件。
c 適用于承插焊和螺紋連接的閥門。
d 適用于鍛鋼制的螺紋管件。
e 適用于鍛鋼制的承插焊和螺紋管件。
f 適用于對焊連接的閥門。
g 適用于鍛鋼制的承插焊管件。