Powered by Google www.ChineseStandard.net Database: 189759 (9 Jun 2024)

GB/T 12224-2015 PDF in English


GB/T 12224-2015 (GB/T12224-2015, GBT 12224-2015, GBT12224-2015)
Standard IDContents [version]USDSTEP2[PDF] delivered inName of Chinese StandardStatus
GB/T 12224-2015English495 Add to Cart 0-9 seconds. Auto-delivery. General requirements for industrial steel valves Valid


Standards related to: GB/T 12224-2015

GB/T 12224-2015: PDF in English (GBT 12224-2015)

GB/T 12224-2015
GB
NATIONAL STANDARD OF THE
PEOPLE’S REPUBLIC OF CHINA
ICS 23.060.01
J 16
Replacing GB/T 12224-2005
General requirements for industrial steel valves
ISSUED ON: DECEMBER 10, 2015
IMPLEMENTED ON: JULY 01, 2016
Issued by: General Administration of Quality Supervision, Inspection and
Quarantine of the People's Republic of China;
Standardization Administration of the People's Republic of
China.
Table of Contents
Foreword ... 5
1 Scope ... 7
2 Normative references ... 7
3 Pressure-temperature rated values ... 11
3.1 General ... 11
3.2 Rated temperature ... 13
3.3 Temperature effects ... 13
3.4 Use instructions for flanged valves’ rated values ... 14
3.5 Deviation ... 14
3.6 Multiple material levels ... 15
3.7 Local operating conditions ... 15
4 Markings ... 15
5 Materials ... 15
5.1 General ... 15
5.2 Material selection ... 16
5.3 Anti-static requirements ... 17
5.4 Removing the end flange ... 17
6 Design requirements ... 17
6.1 Valve body design ... 17
6.2 End dimensions ... 25
6.3 Auxiliary connector ... 28
6.4 Valve assembly ... 31
6.5 Stem ... 33
6.6 Installation restrictions ... 33
6.7 Clip-on valves ... 33
7 Pressure test ... 34
7.1 Housing test ... 34
7.2 Seal test ... 35
7.3 Surface protection ... 36
8 Requirements for special pressure level valves ... 37
8.1 Scope ... 37
8.2 General ... 37
8.3 Required testing ... 37
8.4 Defect removal and repair ... 40
Annex A (normative) Requirements for defined pressure level valves ... 181
A.1 General ... 181
A.2 Pressure-temperature rated values ... 181
A.3 Valve marking ... 182
A.4 Valve body design requirements ... 182
Annex B (normative) Basic formulas for minimum wall thickness ... 185
B.1 Formulas for minimum wall thickness ... 185
B.2 Design values of minimum wall thickness ... 185
Annex C (informative) Relationship between the nominal size of valves and the
basic inner diameter of valve body end ... 186
Annex D (informative) Method for determining pressure-temperature rated
values ... 189
D.1 General ... 189
D.2 Method for determining standard pressure level rated values ... 190
D.3 Method for determining special pressure level rated values ... 193
D.4 Method for determining intermediate pressure level Class rated values
... 194
D.5 Maximum rated values ... 196
Bibliography ... 200
General requirements for industrial steel valves
1 Scope
This Standard specifies the pressure-temperature rated values, materials,
design requirements, inspection and test, markings of steel valves, and
requirements for special pressure level valves and defined pressure level
valves.
This Standard applies to flanged, threaded and welded valves, as well as clip-
on valves and valves for single flange installation, of which the pressure-
bearing members are made using the materials given in Table 1A and Table 1B;
the valve body is made by casting, forged rolling, rolling and assembling-
welding. This Standard includes valves of which the nominal pressure is Class
series and PN series. The range of steel valve parameters to which this
Standard applicable is:
a) The pressure level of Class series valves is Class150 ~ Class4500, of
which Class4500 only applies to welded valves; the pressure level of PN
series valves is PN2.5 ~ PN400;
b) The nominal size of flanged valves is not greater than DN1250;
c) The nominal size of socket welded valves and threaded valves is not
greater than DN65;
d) The rated temperature of threaded valves is not greater than 538 °C, the
pressure level is not greater than Class2500;
e) Flanged valves only apply to standard pressure level and does not apply
to special pressure level and defined pressure level valves;
f) Flanged valves have no intermediate pressure rated values.
2 Normative references
The following referenced documents are indispensable for the application of
this document. For dated references, only the edition cited applies. For undated
references, the latest edition of the referenced document (including any
amendments) applies.
GB 150.1 Pressure vessels - Part 1: General requirements
Table 2-29A ~ Table 2-71A may be in accordance with the requirements of GB/T
9124-2010.
The pressure-temperature rated values of defined pressure level valves do not
exceed the value calculated according to Annex A.
3.1.2 Standard pressure level valves
Valves that meet the requirements of this Standard, except those that meet the
requirements of Clause 8 for special pressure level valves and requirements of
Annex A for defined pressure level valves, are designated as standard pressure
level valves, of which the pressure-temperature rated values comply with the
requirements of 3.1.1.
3.1.3 Special pressure level valves
Valves that meet the requirements of 3.1.2 and meet the inspection
requirements specified in Clause 8 are designated as special pressure level
valves, of which the pressure-temperature rated values comply with the
requirements of 3.1.1. Special pressure level rated values are not available for
flanged end valves.
3.1.4 Defined pressure level valves
Welded or threaded valves that meet the requirements of Annex A for defined
pressure level valves, with the pressure-temperature rated values does not
exceed the value calculated according to Annex A and the nominal size of not
more than DN65 are designated as defined pressure level valves. The
requirements for standard pressure level valves are applicable to defined
pressure level valves, except as otherwise specified in Annex A. The pressure-
temperature rated values of defined pressure level do not apply to flanged
valves.
3.1.5 Intermediate rated value valves
Class series welded or threaded valves, standard pressure level Class400
flanged valves, which can be linearly interpolated to determine the intermediate
rated values between the rated temperature or the rated pressure listed in the
table as specified in 6.1.5. However, for flanged valves of other pressure levels,
linear interpolation is not allowed to be used to determine the nominal pressure
level.
3.1.6 Assembled-and-welded members
Valves assembled-and-welded in whole or in part with castings, forgings, bars,
plates or tubes shall meet the following requirements:
a) The assemble-and-weld of weldments shall be in accordance with the
requirements of GB 150.1 and GB 150.3-2011;
b) The heat treatment of weldments shall be in accordance with the
requirements of GB 150.4;
c) The inspection and acceptance of welds shall be in accordance with the
requirements of GB 150.4;
d) The above requirements do not apply to seal welding or adhesive welding,
such as welding of seat blocks, seat rings, lifting lugs and auxiliary joints.
3.2 Rated temperature
The rated temperature is the temperature indicated by the corresponding
pressure rated value and is the maximum applicable temperature of the
pressure-bearing enclosure of the valve, i.e. the maximum temperature of the
working medium allowed.
3.3 Temperature effects
3.3.1 High temperature
At temperatures in the high temperature creep range, loosening of flanges,
bolts and gaskets will result in a reduction in bolt load. This will reduce the
sealing ability of the flange connection surface. When the temperature rises,
especially the flange connection surface with the nominal pressure not greater
than PN25 and the flange connection surface not larger than Class150 may
cause leakage, so effective measures shall be taken to avoid excessive applied
load or excessive temperature gradient change.
3.3.2 Low temperature
For the materials listed in Table 1A, the pressure rated values with the working
temperature below -29 °C shall not exceed the pressure-temperature rated
values corresponding to -29 °C ~ 38 °C in Table 2-1A ~ Table 2-28A or Table 2-
1B ~ Table 2-28B.
For the materials listed in Table 1B, the pressure rated values with the working
temperature below -10 °C shall not exceed the pressure-temperature rated
values corresponding to -10 °C ~ 50 °C in Table 2-29A ~ Table 2-71A or Table
2-29B ~ Table 2-71B.
Some of the materials listed in Tables 1A and 1B have reduced impact
resistance at low temperatures and the ability to withstand shock loads, sudden
changes in stress, or high levels of stress concentration is also reduced.
as specified in 7.1, but the user shall confirm that there are no restrictions such
as drive units or special materials.
3.6 Multiple material levels
The material of valve body, bonnet or cover plate may be materials of different
standards or different grades. In either case, these materials can be used as
long as they meet the requirements for pressure-temperature rated values.
Mark the material according to the requirements of Clause 4.
3.7 Local operating conditions
When a valve (or valves) is installed in a piping system and operates at different
pressures (or temperatures) on both sides of the closed valve, the pressure and
temperature combinations of the installed valves shall meet the requirements
for the maximum rated value.
4 Markings
The valve marking is in accordance with the requirements of GB/T 12220.
Except for the marking contents specified in GB/T 12220, if the pressure-
temperature rated values of standard pressure level valves are limited by the
material of the internal parts, or if there are other changes, the manufacturer's
nameplate shall include these restrictions or change markings. For example,
valves with non-metallic seals or valves with medium flange bolts using carbon
steel.
For special pressure level valves, valves that meet the special pressure level
requirements of this Standard shall be marked “GB/T 12224 SPL” on the
nameplate.
For defined pressure level valves, valves that meet the defined pressure level
requirements of this Standard shall be marked “GB/T 12224 LTD” on the
nameplate.
5 Materials
5.1 General
5.1.1 The material selection of pressure-bearing members such as valve body,
bonnet or cover plate is as specified in Table 1A or Table 1B.
5.1.2 The pressure-bearing members such as valve body, bonnet or cover plate
may be made of different materials or different types of materials. The material
of the valve body shall be determined according to the applicable pressure-
temperature rated values. The material of the bonnet or cover plate shall be
adapted to the pressure-temperature rated values of the valve body. Valve
stems, discs, and other parts, such as medium flange gaskets and bolts that
are subjected to pressure or other loads, shall be adapted to the pressure-
temperature rated values of the valve.
5.1.3 For valves of which the valve body, bonnet or cover plate is carbon steel,
the nominal pressure is not greater than PN40 and Class300, under the use
condition that the temperature is not greater than 200 °C, the medium flange
connection bolt is allowed to adopt the carbon steel of which the yield strength
is not lower than Class B in ASTM A307-2004, such as 25- and 35-steel in GB/T
699, and marked on the nameplate as specified in Clause 4.
5.1.4 For valves with a nominal size not greater than DN100 and a nominal
pressure not greater than PN100 or not greater than Class600, the valve body
and bonnet or cover plate shall be in accordance with the standard
requirements referenced in Table 1A or Table 1B when investment castings are
used. However, tensile specimens of Ф5 × 25 mm (No. R7 specimen specified
in GB/T 228.1-2010) taken from the same standard melting furnace are allowed
to replace the standard tensile specimens to determine mechanical and
chemical properties. The metal from the standard melting furnace is the metal
that has been previously refurbished separately. The tensile specimen shall be
cast in the same refractory mold as the casting and shall be heat treated the
same as the casting. When investment castings are used for nominal sizes and
nominal pressures greater than the above range, all requirements of the
material standards shall be met.
5.1.5 The appearance quality of pressure-bearing steel castings shall be in
accordance with JB/T 7927.
5.1.6 The mechanical properties of the pressure-bearing members shall be in
accordance with the material standards.
5.2 Material selection
5.2.1 Working conditions
In use, the material has the possibility of qualitative change, the transformation
of carbide phase into graphite, the oxidation of ferrite materials, the lowering of
the toughness of carbon steel even at temperatures above -10 °C, the
sensitivity of intergranular corrosion of austenitic materials, the grain boundary
erosion of nickel-based alloys, etc., which are all factors that need to be
considered.
5.2.2 Other requirements
or calculated in Table 3A or Table 3B, the minimum wall thickness value among
the values may be obtained by linear interpolation method. The minimum wall
thickness of the valve body is required to be measured from the inner surface
of the contact fluid. The minimum wall thickness does not include the thickness
of the lining or bushing.
6.1.3 Inner diameter
The relationship between the basic inner diameter of the valve body end and
the nominal size of the pipe is given in Annex C. To determine the wall thickness
tm, the inner diameter d in Tables 3A, 3B and B shall meet the following
requirements:
a) The inner diameter d is the minimum diameter of the runner, but the
minimum diameter is not less than 90 % of the basic inner diameter of the
valve end. And it shall meet the requirements of 6.1.3b) ~ 6.1.3f);
b) For socket welded and threaded valves, it is not necessary to consider the
socket or tapped hole diameter and associated counterbore or tapped
hole when determining the d value (see 6.2.3, 6.2.4);
c) For multi-stage valve body valves, such as three-stage ball valves [see
Figure 1c)], the valve body is composed of the main valve body and the
left and right valve bodies attached to it. The minimum diameter d of the
left and right valve bodies is not less than 90 % of the basic inner diameter
of the valve end. The main valve body d value shall be the inner diameter
of the main valve body. If the main valve body wall has an axial hole,
whether it is a through hole or a threaded blind hole, the inner and outer
wall thickness shall meet the f and g dimensions requirements in Figure
2;
d) For special cases where the valve is used in the high pressure zone and
low pressure zone of a system, and is specified to be connected to the
end of the thinner pipe wall (or lower pressure level flange), the inner
diameter d shall be determined by connecting to the thicker pipe wall (or
higher pressure level flange), and the minimum wall thickness tm of the
valve shall be selected or calculated according to the higher pressure;
e) The local deviation of the relevant inner diameter of the transition zone
adjacent to the weld groove processing section need not be considered,
except as specified in 6.1.6;
f) Where there is a lining or bushing in the runner, the inner diameter d is the
diameter of the interface between the lining or bushing and the valve body;
g) For the intermediate value of the two inner diameters listed in Table 3A or
body neck of which the diameter is d', including the above 1.1ඥ𝑑𝑡௠
section, the wall thickness shall not be less than t';
c) For the case where the diameter of the valve body neck is much smaller
than the inner diameter of the valve body passage, such as the stem
through hole of the butterfly valve body, i.e. d/d1' ≥ 4 (see Figure 2), the
minimum local wall thickness measured in the L = tm (1 + 1.1ඥ𝑑/𝑡௠ )
section from the intersection of the inner diameter of the valve body and
the outer diameter axis of the valve body neck shall be equal to t', which
is looked up form Table 3A or Table 3B according to the corresponding
inner diameter d1' of the valve body neck and the corresponding pressure
level. The minimum wall thickness of the valve body neck exceeding the
above L = tm (1 + 1.1ඥ𝑑/𝑡௠) section shall be as specified in 6.1.4a), and
shall be looked up from Table 3A or Table 3B according to the diameter d′′;
d) In the case of drilling or tapping the wall of the valve body neck parallel to
the axial direction of the valve body neck, it is required that the sum of the
thickness of the inner and outer lines of the hole is not less than tm or t’,
see f' + g' ≥ t2' in Figure 2. The thickness of the inner side and the thickness
of the bottom of the drilled hole are not less than 0.25tm or 0.25t', see f ≥
0.25tm, j ≥ 0.25tm in Figure 2. And this thickness shall be continued along
the valve body neck, that is, at least from the top of the neck, equal to the
depth of the hole plus the distance of half the hole or bolt diameter.
6.1.5 Intermediate pressure level valves
For intermediate pressure level threaded or welded valves and Class400
flanged valves, the pressure-temperature rated values Pc1 and the minimum
wall thickness tm of the housing shall be in accordance with the requirements
of Annex D, determined using linear interpolation method from formula (D.5) ~
formula (D.12).
6.1.6 Valve body end shape
The valve body end shape shall meet the following requirements:
a) Butt welded end: For the preparation of the welding groove (see 6.2.1), in
the area close to the outer surface of the valve body neck, the housing
wall thickness tm measured along the direction of the runner shall not be
less than the required value tm of 6.1.2 or 6.1.5. The transition to the
welding groove shall be gentle and the cross-section shall be substantially
circular arc throughout the transition zone. The cross-section of the
transition zone shall be such as to avoid intermittent sharp corners or
sharp changes, except for test rings or test sleeves (welded or integral).
The thickness at 2tm from the welding end shall be not less than 0.77tm.
b) Socket welding end and threaded end: As for the distance from the
centerline of the basic cylindrical runner to the outer surface of the valve
body runner, for Class series valves, it shall be not less than 0.5 times the
nominal outer diameter of the tube listed in ASME B36.10M; for PN series
valves, it shall be not less than 0.5 times the nominal outer diameter of
the tube listed in GB/T 17395-2008.
c) End finishing: If only after the housing pressure test required in 7.1, can
the semi-finished product be processed to the final size, the flange sealing
surface is machined to the final surface roughness, and the threaded
connection end is changed to socket welded end. No additional pressure
tests are required after these processes are completed.
6.1.7 Local area
For those of which the wall thickness (t0) of the local area is smaller than the
minimum wall thickness, they are acceptable only if all the following restrictions
are met.
a) An area smaller than the minimum thickness can be surrounded by a circle
having a diameter of not more than 0.35ඥ𝑑଴𝑡଴. For the valve body neck,
d0 = d' and t0 = t' (see 6.1.4). For all other local areas, use d0 = d (see
6.1.3) and t0 = tm (see corresponding 6.1.2 or 6.1.5).
b) The measured thickness is not less than 0.75t0.
c) The distance between the edges of each encircling circle is not less than
1.75ඥ𝑑଴𝑡଴.
6.1.8 Additional thickness allowance
Due to the influence of piping system load, operation (closing and opening) load,
non-circular shape and stress concentration, the housing thickness looked up
form Table 3A or Table 3B requires additional thickness allowance. Since there
are many factors to be considered in the additional thickness allowance, the
additional thickness allowance is determined by the manufacturer according to
the specific situation. Especially the inclined stem valves, of which the
intersection and opening of the valve body cavity is increased, and some of the
assembled-and-welded valve body valves may require additional reinforcement
to ensure adequate strength and rigidity.
......
 
Source: Above contents are excerpted from the PDF -- translated/reviewed by: www.chinesestandard.net / Wayne Zheng et al.