EN 14917:2021/prA1
(Amendment)Metal bellows expansion joints for pressure applications
Metal bellows expansion joints for pressure applications
This document specifies the requirements for design, manufacture and installation of metal bellows expansion joints with circular cross section for pressure applications with maximum allowable pressure greater than 0,5 bar.
Kompensatoren mit metallischen Bälgen für Druckanwendungen
Compensateurs de dilatation à soufflets métalliques pour appareils à pression
Kompenzatorji s kovinskimi mehovi v tlačnih cevovodih - Dopolnilo A1
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
01-december-2024
Kompenzatorji s kovinskimi mehovi v tlačnih cevovodih - Dopolnilo A1
Metal bellows expansion joints for pressure applications
Kompensatoren mit metallischen Bälgen für Druckanwendungen
Compensateurs de dilatation à soufflets métalliques pour appareils à pression
Ta slovenski standard je istoveten z: EN 14917:2021/prA1
ICS:
23.040.99 Drugi sestavni deli za Other pipeline components
cevovode
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
DRAFT
EUROPEAN STANDARD
EN 14917:2021
NORME EUROPÉENNE
EUROPÄISCHE NORM
prA1
September 2024
ICS 23.040.99
English Version
Metal bellows expansion joints for pressure applications
Compensateurs de dilatation à soufflets métalliques Kompensatoren mit metallischen Bälgen für
pour appareils à pression Druckanwendungen
This draft amendment is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee CEN/TC 342.
This draft amendment A1, if approved, will modify the European Standard EN 14917:2021. If this draft becomes an amendment,
CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for inclusion of
this amendment into the relevant national standard without any alteration.
This draft amendment was established by CEN in three official versions (English, French, German). A version in any other
language made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC
Management Centre has the same status as the official versions.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and
United Kingdom.
Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are
aware and to provide supporting documentation.
Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without
notice and shall not be referred to as a European Standard.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2024 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 14917:2021/prA1:2024 E
worldwide for CEN national Members.
Contents Page
European foreword . 4
1 Modification to the European foreword . 5
2 Modification to Clause 2, “Normative references” . 5
3 Modification to 6.1.1, “Symbols” . 5
4 Modification to 6.1.2.1, “General” . 5
5 Modification to 6.1.3.5, “Design on PS basis” . 5
6 Modifications to 6.2.2.5.1, “General intermediate factors” . 5
7 Modification to 6.2.3.3.2.2, “In-plane instability” . 6
8 Modification to 6.2.4.4.1, “Stresses due to equivalent axial displacement” . 6
9 Modification to 6.2.5.2, “Limitations” . 6
10 Modification to 6.2.5.3.2, “Additional factors” . 6
11 Modifications to 6.2.5.3.2, “Additional factors” . 6
12 Modification to 6.2.6.1, “General” . 6
13 Modification to 6.2.8.2, “Total equivalent axial expansion and compression” . 6
14 Modification to 6.2.8.4.2, “Increasing factors for single bellows” . 7
15 Modifications to 6.2.9.2.2, “Working forces and moments” . 7
16 Modification to 6.2.9.3, “Type of expansion joint” . 7
17 Modification to 6.2.10, “Torsion acting on bellows (unreinforced or reinforced)” . 7
18 Modification to 7.4.1.2, “Limitations of the cold forming process” . 7
19 Modifications to 8.4.4, “Non-destructive testing of welds” . 8
20 Modification to Annex K (normative), “Hardware calculation” . 8
21 Modification to K.4.1, “General” . 9
22 Modification to K.5, “Pin”. 9
23 Modification to K.7.3.2, “Instability” . 9
24 Modification to K.7.3, “Square type gimbal” . 9
25 Modification to K.7.4, “Round type gimbal” . 11
26 Modification to K.8.1.1, “General” . 11
27 Modification to K.8.1.2, “Stress in plate for section 3” . 11
28 Modification to K.8.1.3, “Stress in sections for form-lock connection (lugs for
hinge/gimbal” . 11
29 Modification to K.8.1.4, “Stress in sections for welded buttonhole connection (lugs
for hinge/gimbal)” . 13
30 Modification to K.8.1.6, “Stress in the weld plate/pipe” . 13
31 Modification to K.8.2.2, “Stress in the plate” . 13
32 Modification to K.9.2.1, “General” . 13
33 Modification to K.9.2.3, “Stresses in Section 2” . 14
34 Modification to K.9.3.2, “Weld between lug plate and attachment plate” . 15
35 Modification to K.10.1.1, “Stress in flange with 2 tie bars or lugs” . 15
36 Modification to K.10.1.2, “Stress in flange with more than 2 tie bars” . 15
37 Modification to K.10.2.1, “Stress in plate welded on flange with 2 tie bars” . 15
38 Modification to K.12, “Gusset with reinforcing rings” . 15
39 Modification to K.12.2 , “Basic definitions” . 15
40 Modification to K.12.3 , “Stresses in the gussets” . 15
41 Addition of Annex L (informative), “Benchmarks for calculation” . 15
European foreword
This document (EN 14971:2021/prA1:2024) has been prepared by Technical Committee CEN/TC 342
“Metal hoses, hose assemblies, bellow and expansion joints”, the secretariat of which is held by SNV.
This document is currently submitted to the CEN Enquiry.
This document has been prepared under a standardization request addressed to CEN by the European
Commission. The Standing Committee of the EFTA States subsequently approves these requests for its
Member States.
For the relationship with EU Legislation, see informative Annex ZA, which is an integral part of
EN 14971:2021.
1 Modification to the European foreword
Replace paragraphs 5 and 6 with the following:
“This document has been prepared under a standardization request addressed to CEN by the European
Commission. The Standing Committee of the EFTA States subsequently approves these requests for its
Member States.
For the relationship with EU Legislation, see informative Annex ZA, which is an integral part of this
document.”
2 Modification to Clause 2, “Normative references”
In Clause 2 and throughout the document replace:
"EN 13445-2:2014" with "EN 13445-2:2024".
"EN 13445-3:2014" with "EN 13445-3:2021".
3 Modification to 6.1.1, “Symbols”
Insert the following new symbols in Table 4 in the appropriate order in the table:
“
l the length of the tie rod measured between the centre points of the bearing spheres".
R
𝑟𝑟 mean radius of crest and root knuckle of U-shaped corrugations (see formula 26) and all mean
𝑚𝑚
radius of torus (see Figure 16)".
4 Modification to 6.1.2.1, “General”
Add the following paragraphs before the NOTE:
"For material properties, Clause 5 applies.
If material properties are used to calculate expansion joints in this standard that are not available, like
values in the creep range, special considerations should be taken into account. Examples are advanced
non-linear calculations and component tests. The safety philosophy of the PED and the latest state-of-the-
art knowledge apply.
For the allowable stresses, see 6.1.3.3.".
5 Modification to 6.1.3.5, “Design on PS basis”
Below Formula (3), add the following:
“where
𝑅𝑅
𝑝𝑝𝑝𝑝
𝑘𝑘 = ".
𝑝𝑝,𝑡𝑡
𝑅𝑅
𝑝𝑝𝑝𝑝𝑝𝑝
6 Modifications to 6.2.2.5.1, “General intermediate factors”
Delete the outside brackets in Formula (22).
Replace "L " with "L ; L " in Formula (33).
c c t
7 Modification to 6.2.3.3.2.2, “In-plane instability”
Replace "min" with "max" in the whole clause.
8 Modification to 6.2.4.4.1, “Stresses due to equivalent axial displacement”
Replace Formula (144) with:
“
∗
3∙𝐸𝐸 ∙𝑒𝑒
B,20 p
𝜎𝜎 (∆q) = ∙∆q
m,b
2 2 2
( )
2 ∙ (1−𝜗𝜗 )∙ 𝑤𝑤−𝐶𝐶 ∙𝑟𝑟 ∙𝑐𝑐 ∙𝐶𝐶
r 𝑚𝑚 c(d) d
”.
9 Modification to 6.2.5.2, “Limitations”
In Formula (146) and (147), replace "r" with "𝑟𝑟 ".
𝑖𝑖
10 Modification to 6.2.5.3.2, “Additional factors”
In Formula (152), replace "r" with "𝑟𝑟 ".
𝑚𝑚
11 Modifications to 6.2.5.3.2, “Additional factors”
In Table 11, line D , replace “Formula (148)” with “Formula (150)”.
iC
12 Modification to 6.2.6.1, “General”
Add the following sentence:
“This clause is relevant for all types of described bellows in 6.2.3, 6.2.4 and 6.2.5.”.
13 Modification to 6.2.8.2, “Total equivalent axial expansion and compression”
Replace Formula (197) with the following:
“
∆𝑞𝑞
𝑒𝑒,𝑎𝑎𝑎𝑎𝑎𝑎
0,5
0,67
𝑤𝑤 𝑅𝑅
𝑝𝑝1,0,𝑡𝑡
⎧ 𝑚𝑚
0,1336∙� � ∙�𝑟𝑟 ∙�𝐷𝐷 + 2∙𝑤𝑤 +𝑒𝑒)∙𝑐𝑐∙ (𝑠𝑠 ) ∙ � ∙ (𝑞𝑞−∆𝐿𝐿− 4∙𝑟𝑟 ) 𝑤𝑤𝑤𝑤𝑤𝑤ℎ 𝑐𝑐𝑐𝑐𝑐𝑐𝑐𝑐 𝑤𝑤𝑐𝑐𝑟𝑟𝑘𝑘
𝑚𝑚 𝑖𝑖 𝑑𝑑 𝑚𝑚
⎪
2∙𝑟𝑟 𝑅𝑅
𝑚𝑚 𝑝𝑝1,0
≤
0,5
⎨ 𝑤𝑤 𝑅𝑅
𝑝𝑝1,0,𝑡𝑡
0,1336� ��𝑟𝑟 ∙�𝐷𝐷 + 2∙𝑤𝑤 +𝑒𝑒)∙ � ∙ (𝑞𝑞−∆𝐿𝐿− 4∙𝑟𝑟 ) 𝑓𝑓𝑐𝑐𝑟𝑟 𝑏𝑏𝑒𝑒𝑐𝑐𝑐𝑐𝑐𝑐𝑤𝑤𝑠𝑠 𝑎𝑎𝑎𝑎𝑎𝑎𝑒𝑒𝑎𝑎𝑐𝑐𝑒𝑒𝑐𝑐 𝑎𝑎𝑐𝑐𝑐𝑐.𝑤𝑤𝑐𝑐 𝑇𝑇𝑎𝑎𝑏𝑏𝑐𝑐𝑒𝑒 8 (𝑤𝑤𝑤𝑤𝑤𝑤ℎ𝑐𝑐𝑜𝑜𝑤𝑤 𝑐𝑐𝑐𝑐𝑐𝑐𝑐𝑐 𝑤𝑤𝑐𝑐𝑟𝑟𝑘𝑘)
⎪
𝑚𝑚 𝑖𝑖 𝑚𝑚
2∙𝑟𝑟 𝑅𝑅
𝑚𝑚 𝑝𝑝1,0
⎩
”.
Add the following sentence after the formula: "For s , see Formulae (268), (269), (270).".
d
14 Modification to 6.2.8.4.2, “Increasing factors for single bellows”
Replace Formula (208) with the following:
"
1 𝑓𝑓𝑐𝑐𝑟𝑟 𝜅𝜅⋅ (𝑐𝑐 ⁄2) = 0
𝐵𝐵
� ( ⁄ )
𝑐𝑐̂= 𝜅𝜅⋅𝑎𝑎 2 𝑎𝑎
𝐵𝐵 𝐵𝐵
𝑃𝑃Θ
𝑓𝑓𝑐𝑐𝑟𝑟 0 <𝜅𝜅⋅� � < 𝜋𝜋
[ ( /2)] 2
𝑠𝑠𝑖𝑖𝑠𝑠𝜅𝜅⋅𝑎𝑎
𝐵𝐵
with κ according to Formula (48)."
Replace Formula 209 with the following formula and definition:
"
1 𝑓𝑓𝑐𝑐𝑟𝑟 𝜅𝜅⋅𝑐𝑐 ≤𝜋𝜋/4
𝐵𝐵
𝑐𝑐̂=� 3,5
𝑃𝑃𝑃𝑃 4,8
) ]
𝑚𝑚𝑎𝑎𝑚𝑚�1;�2,33− �⋅ [0,5 + 0,015⋅ (𝜅𝜅⋅𝑐𝑐 � 𝑓𝑓𝑐𝑐𝑟𝑟 𝜋𝜋/4 <𝜅𝜅⋅𝑐𝑐 ≤ 𝜋𝜋/√2
𝐵𝐵 𝐵𝐵
∗
𝑎𝑎 /𝑎𝑎
𝐵𝐵
with κ according to Formula (48).".
Delete Formula (210).
15 Modifications to 6.2.9.2.2, “Working forces and moments”
In Table 14, row 2.4816, change the allocation for column n from R to R
t p1,0 p0,2.
16 Modification to 6.2.9.3, “Type of expansion joint”
In Formula (214), replace "𝐾𝐾 " 𝑤𝑤𝑤𝑤𝑤𝑤ℎ "𝐾𝐾 ".
𝜇𝜇𝜇𝜇 𝜇𝜇𝜇𝜇,𝑡𝑡
In Formula (219), replace "μ" with "𝜇𝜇̅ " (only one dash!).
In Formula (228), replace "�𝜇𝜇�� " with "𝜇𝜇̅ ".
𝑝𝑝
Delete the following list item after Formulae (222) and (231):
“iii. the length of the tie rod l measured between the centre points of the bearing spheres”.
R
17 Modification to 6.2.10, “Torsion acting on bellows (unreinforced or
reinforced)”
Add the following sentence after Formula (253):
"The angle of twist of more than one bellows is calculated by 𝑀𝑀 ∗𝑎𝑎 .”.
B
𝑡𝑡,𝑎𝑎𝑎𝑎𝑎𝑎
Add the following sentence after Formula (256):
“The torsional moment of more than one bellows is calculated by 𝑀𝑀 /n .”.
B
𝑡𝑡,𝑎𝑎𝑎𝑎𝑎𝑎
In Formula (256), replace "KB" with "KB,t".
In the Note after Formula
...
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