SIST EN 16603-35-06:2014
(Main)Space engineering - Cleanliness requirements for spacecraft propulsion hardware
Space engineering - Cleanliness requirements for spacecraft propulsion hardware
ECSS-E-ST-35-06 belongs to the Propulsion field of the mechanical discipline, and concerns itself with the cleanliness of propulsion components, sub-systems and systems The standard - defines design requirements which allow for cleaning of propulsion components sub-systems and systems and which avoid generation or unwanted collection of contamination, - identifies cleanliness requirements (e.g. which particle / impurity / wetness level can be tolerated), - defines requirements on cleaning to comply with the cleanliness level requirements, and the requirements on verification, - identifies the cleanliness approach, cleaning requirements, (e.g. what needs to be done to ensure the tolerable level is not exceeded, compatibility requirements), - identifies, specifies and defines the requirements regarding conditions under which cleaning or cleanliness verification takes place (e.g. compatibility, check after environmental test). The standard is applicable to the most commonly used propulsion systems and their related storable propellant combinations: Hydrazine (N2H4), Mono Methyl Hydrazine (CH3N2H3), MON (Mixed Oxides of Nitrogen), Nitrogen (N2), Helium (He), Propane (C3H8), Butane (C4H10) and Xenon (Xe). This standard is the basis for the European spacecraft and spacecraft propulsion industry to define, achieve and verify the required cleanliness levels in spacecraft propulsion systems. This standard is particularly applicable to spacecraft propulsion as used for satellites and (manned) spacecraft and any of such projects including its ground support equipment. External cleanliness requirements, e.g. outside of tanks, piping and aspects such as fungus and outgassing are covered by ECSS-Q-ST-70-01. This standard may be tailored for the specific characteristic and constraints of a space project in conformance with ECSS-S-ST-00.
Raumfahrttechnik - Sauberkeitsanforderungen für die Antriebstechnik von Raumfahrtzeugen
Ingénierie spatiale - Exigences de propreté des éléments de propulsion des véhicules spatiaux
Vesoljska tehnika - Zahteve za čistočo pogonske tehnike vesoljskih plovil
Standard ECSS-E-ST-35-06 sodi na pogonsko področje strojništva in zajema zahteve za čistočo pogonskih sestavnih delov, podsistemov in sistemov Standard - določa zahteve za projekt, ki omogočajo čiščenje pogonskih sestavnih delov podsistemov in sistemov in ki se izognejo nastajanju ali neželenemu nabiranju onesnaženja, - opredeljuje zahteve za čistočo (npr. kateri delec/nečistoča/raven vlažnosti je še dopusten), - določa zahteve glede čiščenja v skladu z zahtevami ravni čistoče in zahtevami za verifikacijo, - opredeljuje pristop za čistočo, zahteve za čiščenje (npr. kaj je treba storiti, da se zagotovi, da dopustna raven ni presežena, zahteve za združljivost), - opredeljuje, specificira in določa zahteve v zvezi s pogoji, pod katerimi poteka preverjanje čiščenja ali čistoče (npr. združljivost, preverjanje po okoljskem preskusu). Ta standard velja za večino najbolj pogosto uporabljenih pogonskih sistemov in njihovih povezanih, shranjenih kombinacij goriv: hidrazin (N2H4), monometil hidrazin (CH3N2H3), MON (mešani dušikovi oksidi), dušik (N2), helij (He), propan (C3H8), butan (C4H10) in ksenon (Xe). Ta standard je temelj za industrijo evropskih vesoljskih plovil in pogonsko industrijo za vesoljska plovila za določitev, doseganje in preverjanje zahtevanih ravni čistoče v pogonskem sistemu vesoljskega plovila. Ta standard še zlasti velja za pogon vesoljskih plovil, kot se uporablja za satelite in vesoljska plovila (s posadko) in katerega koli od teh projektov, vključno s podporno opremo na tleh. Zahteve za zunanjo čistočo, npr. izven rezervoarjev in cevi, in vidiki, kot so glive in razplinjevanje, so zajete v standardu ECSS-Q-ST-70-01. Ta standard se lahko prilagodi posameznim lastnostim in omejitvam vesoljskega projekta v skladu s standardom ECSS-S-ST-00.
General Information
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Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN 16603-35-06:2014
01-november-2014
9HVROMVNDWHKQLND=DKWHYH]DþLVWRþRSRJRQVNHWHKQLNHYHVROMVNLKSORYLO
Space engineering - Cleanliness requirements for spacecraft propulsion hardware
Raumfahrttechnik - Sauberkeitsanforderungen für die Antriebstechnik von
Raumfahrtzeugen
Ingénierie spatiale - Exigences de propreté des éléments de propulsion des véhicules
spatiaux
Ta slovenski standard je istoveten z: EN 16603-35-06:2014
ICS:
49.140 Vesoljski sistemi in operacije Space systems and
operations
SIST EN 16603-35-06:2014 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST EN 16603-35-06:2014
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SIST EN 16603-35-06:2014
EUROPEAN STANDARD
EN 16603-35-06
NORME EUROPÉENNE
EUROPÄISCHE NORM
September 2014
ICS 49.140
English version
Space engineering - Cleanliness requirements for spacecraft
propulsion hardware
Ingénierie spatiale - Exigences de propreté des éléments Raumfahrttechnik - Sauberkeitsanforderungen für die
de propulsion des véhicules spatiaux Antriebstechnik von Raumfahrtzeugen
This European Standard was approved by CEN on 1 March 2014.
CEN and CENELEC members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving
this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning
such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN and CENELEC
member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation
under the responsibility of a CEN and CENELEC member into its own language and notified to the CEN-CENELEC Management Centre
has the same status as the official versions.
CEN and CENELEC members are the national standards bodies and national electrotechnical committees of Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece,
Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia,
Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom.
CEN-CENELEC Management Centre:
Avenue Marnix 17, B-1000 Brussels
© 2014 CEN/CENELEC All rights of exploitation in any form and by any means reserved Ref. No. EN 16603-35-06:2014 E
worldwide for CEN national Members and for CENELEC
Members.
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SIST EN 16603-35-06:2014
EN 16603-35-06:2014 (E)
Table of contents
Foreword . 6
1 Scope . 7
2 Normative references . 8
3 Terms, definitions and abbreviated terms . 10
3.1 Terms from other standards . 10
3.2 Terms specific to the present standard . 10
3.3 Abbreviated terms. 13
3.4 Symbols . 13
4 Cleanliness requirements . 14
4.1 General . 14
4.2 Design requirements . 15
4.2.1 General . 15
4.2.2 Components. 15
4.2.3 System . 17
4.2.4 Ground support equipment (GSE) . 17
4.3 Manufacturing . 18
4.3.1 General . 18
4.3.2 Manufacturing processes . 18
4.3.3 Machined parts . 18
4.3.4 Tubing and manifolds . 18
4.3.5 Components. 20
4.3.6 Subsystems and systems. 21
4.3.7 Final rinsing solutions . 21
4.4 Cleanliness classes definition . 22
4.4.1 Particulate . 22
4.4.2 Non-volatile residues (NVR) . 25
4.4.3 Dryness and liquid residuals . 25
4.4.4 Requirements on process fluids to meet cleanliness classes . 26
4.5 Test methods . 27
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4.6 Code usage . 27
5 Cleaning techniques . 28
5.1 General . 28
5.2 Environment, health and safety. 29
5.2.1 General . 29
5.2.2 Hardware configuration requirements. 29
5.2.3 Cleaning process approval . 30
5.3 Pre-cleaning . 30
5.3.1 General . 30
5.3.2 Mechanical pre-cleaning . 30
5.3.3 Chemical pre-cleaning . 31
5.4 Precision cleaning. 32
5.4.1 General . 32
5.4.2 Re-cleaning operational systems . 32
5.5 Drying methods . 33
5.5.1 General . 33
5.5.2 Gaseous purge-drying . 33
5.5.3 Drying sample . 34
5.5.4 Flow rates during purging . 35
5.5.5 Vacuum drying procedure . 35
5.6 Excepted components, subsystems and systems . 36
6 Cleanliness verification requirements . 37
6.1 Surface . 37
6.1.1 Visual and UV inspection . 37
6.1.2 pH-test . 37
6.2 Acceptance inspection of items cleaned in a controlled environment . 38
6.2.1 General . 38
6.2.2 Test fluids . 38
6.2.3 Test fluid volume for analysis . 39
6.2.4 Analysis of test fluid-flush sample (solvent) . 39
6.2.5 Analysis of aqueous-based, liquid-flush sample . 40
6.2.6 Drying . 41
6.2.7 Vacuum drying . 41
6.3 Maintaining cleanliness . 42
6.3.1 Pressurant gas purge . 42
6.3.2 Installation and marking of temporary hardware . 42
6.3.3 Temporary hardware replacement . 42
3
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6.3.4 Component replacement . 43
6.4 Dryness verification . 43
6.4.1 General . 43
6.4.2 Purge dryness . 43
6.4.3 Vacuum dryness . 43
6.4.4 Sample test and qualified procedure . 44
7 Acceptance inspection of packaging materials . 45
7.1 Environmental control . 45
7.2 Sampling . 45
7.3 Thickness of packaging film . 45
7.4 Static electricity . 46
7.5 Verification of cleanliness level . 46
7.5.1 General . 46
7.5.2 Minimum surface area for test . 46
7.5.3 Sample preparation . 46
7.5.4 Rinsing procedures . 47
8 Packaging and protection . 48
8.1 Approved coverings . 48
8.2 Packaging operations . 48
8.3 Certification labels . 49
9 Deliverables . 50
10 Test procedures . 51
10.1 Test liquid-flush procedure (solvent) . 51
10.2 Gas flow test procedure . 51
11 Sampling and analytical practices . 52
11.1 Cleanliness level test methods. 52
11.1.1 General . 52
11.1.2 Method I “Liquid Flush Test” . 52
11.1.3 Method II “Liquid Flow Test” . 53
11.1.4 Method III “Gas Flow Test” . 53
11.1.5 Method IV “Liquid flow test under operating conditions” . 53
12 Determination of particle population and NVR analysis . 55
12.1 Microscopic particle population . 55
12.2 Gravimetric NVR analysis method . 56
4
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EN 16603-35-06:2014 (E)
Annex A (normative) Cleanliness Requirements Analysis (CRA) for
spacecraft propulsion components, subsystems and systems - DRD . 57
Annex B (normative) Cleaning Technique Selection (CTS) for spacecraft
propulsion components, subsystems and systems - DRD . 59
Annex C (normative) Cleanliness Certificate (CC) for spacecraft
propulsion components, subsystems and systems - DRD . 61
Annex D (normative) Typical test and cleaning liquids. 64
Annex E (informative) Pre-cleaning sequences . 67
Annex F (informative) Cleanliness certificate . 69
Bibliography . 71
Figures
Figure F-1 : Example of a cleanliness certificate. 70
Tables
Table 4-1: Cleanliness classes . 24
Table 4-2: NVR contamination levels . 25
Table 4-3: Visible contamination levels . 27
Table 7-1: Packaging materials . 46
Table E-1 : Typical pre-cleaning sequence for common materials . 67
5
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EN 16603-35-06:2014 (E)
Foreword
This document (EN 16603-35-06:2014) has been prepared by Technical
Committee CEN/CLC/TC 5 “Space”, the secretariat of which is held by DIN.
This standard (EN 16603-35-06:2014) originates from ECSS-E-ST-35-06C rev.1.
This European Standard shall be given the status of a national standard, either
by publication of an identical text or by endorsement, at the latest by March
2015, and conflicting national standards shall be withdrawn at the latest by
March 2015.
Attention is drawn to the possibility that some of the elements of this document
may be the subject of patent rights. CEN [and/or CENELEC] shall not be held
responsible for identifying any or all such patent rights.
This document has been prepared under a mandate given to CEN by the
European Commission and the European Free Trade Association.
This document has been developed to cover specifically space systems and has
therefore precedence over any EN covering the same scope but with a wider
domain of applicability (e.g. : aerospace).
According to the CEN-CENELEC Internal Regulations, the national standards
organizations of the following countries are bound to implement this European
Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic,
Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France,
Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,
Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania,
Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United
Kingdom.
6
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SIST EN 16603-35-06:2014
EN 16603-35-06:2014 (E)
1
Scope
ECSS-E-ST-35-06 belongs to the Propulsion field of the mechanical discipline,
and concerns itself with the cleanliness of propulsion components, sub-systems
and systems
The standard
• defines design requirements which allow for cleaning of propulsion
components sub-systems and systems and which avoid generation or
unwanted collection of contamination,
• identifies cleanliness requirements (e.g. which particle / impurity /
wetness level can be tolerated),
• defines requirements on cleaning to comply with the cleanliness level
requirements, and the requirements on verification,
• identifies the cleanliness approach, cleaning requirements, (e.g. what
needs to be done to ensure the tolerable level is not exceeded,
compatibility requirements),
• identifies, specifies and defines the requirements regarding conditions
under which cleaning or cleanliness verification takes place (e.g.
compatibility, check after environmental test).
The standard is applicable to the most commonly used propulsion systems and
their related storable propellant combinations: Hydrazine (N2H4), Mono Methyl
Hydrazine (CH3N2H3), MON (Mixed Oxides of Nitrogen), Nitrogen (N2),
Helium (He), Propane (C3H8), Butane (C4H10) and Xenon (Xe).
This standard is the basis for the European spacecraft and spacecraft propulsion
industry to define, achieve and verify the required cleanliness levels in
spacecraft propulsion systems.
This standard is particularly applicable to spacecraft propulsion as used for
satellites and (manned) spacecraft and any of such projects including its ground
support equipment.
External cleanliness requirements, e.g. outside of tanks, piping and aspects such
as fungus and outgassing are covered by ECSS-Q-ST-70-01.
This standard may be tailored for the specific characteristic and constraints of a
space project in conformance with ECSS-S-ST-00.
7
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EN 16603-35-06:2014 (E)
2
Normative references
The following normative documents contain provisions which, through
reference in this text, constitute provisions of this ECSS Standard. For dated
references, subsequent amendments to, or revisions of any of these
publications, do not apply. However, parties to agreements based on this ECSS
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 publication referred to applies.
EN reference Reference in text Title
EN 16601-00-01 ECSS-S-ST-00-01 ECSS system — Glossary of terms
EN 16603-35 ECSS-E-ST-35 Space engineering — Propulsion general
requirements
EN 16602-40 ECSS-Q-ST-40 Space product assurance — Safety
EN 16602-70-01 ECSS-Q-ST-70-01 Space product assurance — Cleanliness and
contamination control.
EN 16602-70 ECSS-Q-ST-70 Space product assurance — Materials, mechanical
parts and processes
ISO 2210:1972 Liquid halogenated hydrocarbons for industrial use-
Determination of residue on evaporation
ISO 5789:1979 Fluorinated hydrocarbons for industrial use —
Determination of non-volatile residue
ISO 5884:1978 Aerospace — Fluid systems and components —
Methods for system sampling and measuring the
solid particle contamination of hydraulic fluids
ISO 14951-3:2000 Space systems —Fluid characteristics —Part 3:
Nitrogen
ISO 14951-4:2000 Space systems — Fluid characteristics —Part 4:
Helium
ISO 14951-10:2000 Space systems — Fluid characteristics —Part 10:
Water
ISO 14952-3:2003 Space systems — Surface cleanliness of fluid systems
— Part 3: Analytical procedures for the
determination of non-volatile residues and
particulate contamination
8
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EN 16603-35-06:2014 (E)
ASTM D257(99) 2005 Standard Test Method for DC Resistance or
Conductance of Insulating Materials
ASTM D329 10 Dec Standard specification for Acetone
2002
ASTM D740 Standard specification for Methyl Ethyl Ketone
15 May 2005
ASTM D770-05 Standard specification for Isopropyl Alcohol
15 May 2005
ASTM D1152 Standard specification for Methanol (Methyl Alcohol)
1 Apr 2006
ASTM D1293 10 Dec Standard test methods for pH of water
1999
ASTM D4376 Standard specification for vapor-degreasing grade
Perchloroethylene
MIL-PRF-27415B Performance specification, propellant pressurizing
8 Feb 2007 agent, Argon
O-E-760D Federal specification
28 May 1987
SEMI C47-0699 Guideline for Trans 1,2 Dichloroethylene
May 1999
9
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EN 16603-35-06:2014 (E)
3
Terms, definitions and abbreviated terms
3.1 Terms from other standards
For the purpose of this Standard, the terms and definitions from ECSS-S-ST-00-01
and ECSS-E-ST-35 apply.
3.2 Terms specific to the present standard
3.2.1 accuracy
measure of how close a value is to the “true” value
3.2.2 blank
result for an analytical sample of the virgin test fluid prior to use in performing
a cleanliness verification test
3.2.3 cleanliness verification
activity intended to verify that the actual cleanliness conditions of an item are in
conformance with the applicable specification
3.2.4 condensable hydrocarbon
hydrocarbon capable of going from a gaseous to a liquid or solid state at
ambient temperature and pressure
3.2.5 crazing
creating microvoids in glassy thermoplastic polymers preceding the formation of
cracks
3.2.6 critical surface
any surface of an item that contacts the service medium
NOTE Examples of service media are propellants and
pressurants.
3.2.7 dewar
double-walled vessel with the annular space between the walls evacuated to
provide insulation
10
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EN 16603-35-06:2014 (E)
3.2.8 dew point
temperature at which condensation of water vapour takes place at prevailing
pressure
NOTE The prevailing pressure is usually atmospheric
pressure.
3.2.9 fibre
flexible structure having a length-to-width ratio of 10 to 1 or greater
NOTE 1 A fibre is considered to be a particle, see clause
3.2.14.
NOTE 2 The size of a fibre is its maximum length.
3.2.10 field cleaning
processes of pre-cleaning and precision cleaning of components, subsystems
and systems which cannot be processed in a controlled environment such as a
clean room
3.2.11 generally clean
free from manufacturing residue, dirt, oil, grease, processing debris, or other
extraneous contamination based on visual examination
3.2.12 high-efficiency particulate air filter
filter that is at least 99,97 % efficient by volume on 0,3 μm particles
3.2.13 non-volatile residue
soluble or suspended material and insoluble particulate matter remaining after
temperature-controlled evaporation of a volatile liquid
NOTE See also clause 6.2.4.3
3.2.14 particle
unit of solid matter with observable size
NOTE 1 Various methods for defining its size may be
used and are dependant upon the measurement
technique.
NOTE 2 For the manual method the apparent maximum
linear dimension of a particle in the plane of
observation as observed with instruments such
as optical, electron, or atomic force microscopes
is the particle size.
NOTE 3 For the automatic method, the equivalent
diameter of a particle detected by automatic
instrumentation is the particle size.
NOTE 4 The equivalent diameter is the diameter of a
reference sphere having known properties and
producing the same response in the sensing
instrument as the particle being measured.
NOTE 5 A fibre is considered a particle, see clause 3.2.9.
11
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EN 16603-35-06:2014 (E)
3.2.15 passivation
process by which a corrosion-resistant layer is formed on a metal surface by
submersing the surface in an acid solution
3.2.16 pickling
chemical or electrochemical process by which surface oxides are removed from
metals
3.2.17 precision cleaning
cleaning process used to achieve cleanliness levels more stringent than visibly
clean
3.2.18 pre-cleaning
cleaning process normally used to achieve the visibly clean cleanliness level
3.2.19 reversion
decrease in viscosity, strength, or in rubber modulus due to heating or
overworking, resulting in a tacky and soft material
3.2.20 silting
accumulation of particles of sufficient quantity to cause a haze or obscuring of
any portion of a filter membrane when viewed visually or under 40-power
maximum magnification
3.2.21 test fluid
specified fluid that is utilized to determine the fluid system wetted-surface
cleanliness level
3.2.22 threshold limit value
maximum average daily dosage, based on an 8-h day, 5-day week, to which an
average worker may be exposed to hazardous chemicals without harmful effect
NOTE 1 The TLV is a time-weighted average
concentration.
NOTE 2 The TLV is normally expressed in parts of the
gas or vapour in micro litres per litre.
3.2.23 visibly clean
absence of surface contamination when examined with a specific light source,
angle of incidence, and viewing distance using normal or magnified vision up
to ×20
3.2.24 visibly clean plus ultraviolet
cleaning level that is visibly clean and also meets the requirements for
inspection with the aid of an ultraviolet light of wavelength 250 nm to 395 nm
3.2.25 volatile hydrocarbon
hydrocarbon capable of going from liquid or solid to a gaseous state at ambient
temperature and pressure
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3.3 Abbreviated terms
For the purpose of this Standard, the abbreviated terms from ECSS-S-ST-00-01
and the following apply:
Abbreviation Meaning
CC cleanliness certificate
CRA
cleaning requirement analysis
CTS cleaning technique selection
GC
generally clean
HEPA high-efficiency particulate air filter
HFE
hydro fluor ether (Per fluoro-n-butyl methyl ether)
IPA isopropanol
MAIT manufacturing, assembly, integration and test
MEK methyl ethyl keton
MS
mass spectroscopy
NVR non-volatile residue
ppmv parts per million, volumetric
TLV threshold limit value
US ultra sonic
VC visibly clean
VC + UV visibly clean plus ultraviolet
3.4 Symbols
Symbol
Meaning
dp mean pore diameter of a filter
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EN 16603-35-06:2014 (E)
4
Cleanliness requirements
4.1 General
a. This standard shall only apply to propulsion systems using Hydrazines,
MON, Propane, Butane, Nitrogen, Helium, Xenon as propellants.
b. Cleanliness assurance precautions and features shall be specified and
incorporated in the hardware at the design phase.
NOTE In propulsion systems cleanliness is a major
requirement to avoid loss of function and
performance.
c. Cleanliness verification shall be applied at progressive MAIT stages in
the process.
d. The hardware shall be designed to enable post-build cleaning and
cleanliness verification.
e. Operation and use shall not generate or release contamination.
f. A cleanliness verification should be performed successively at
component, sub-system and system level prior to a blind-end close-out.
g. Cleanliness Particle Count levels shall be to a lower required class or
subclass at the early hardware build and verification stages, than the final
product.
NOTE 1 This allows final system-level cleanliness to be
achieved.
NOTE 2 See Table 4-1: for cleanliness classes and
subclasses.
h. During the design phase the necessity of cleanliness verification shall be
assessed.
N
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