EP1258670A2 - Gas containment system - Google Patents

Gas containment system Download PDF

Info

Publication number
EP1258670A2
EP1258670A2 EP02253134A EP02253134A EP1258670A2 EP 1258670 A2 EP1258670 A2 EP 1258670A2 EP 02253134 A EP02253134 A EP 02253134A EP 02253134 A EP02253134 A EP 02253134A EP 1258670 A2 EP1258670 A2 EP 1258670A2
Authority
EP
European Patent Office
Prior art keywords
gas
chamber
pressure
containment system
regulatory
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP02253134A
Other languages
German (de)
French (fr)
Other versions
EP1258670A3 (en
Inventor
James Robert Smith
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
BOC Group Ltd
Original Assignee
BOC Group Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by BOC Group Ltd filed Critical BOC Group Ltd
Publication of EP1258670A2 publication Critical patent/EP1258670A2/en
Publication of EP1258670A3 publication Critical patent/EP1258670A3/en
Withdrawn legal-status Critical Current

Links

Images

Classifications

    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F17STORING OR DISTRIBUTING GASES OR LIQUIDS
    • F17CVESSELS FOR CONTAINING OR STORING COMPRESSED, LIQUEFIED OR SOLIDIFIED GASES; FIXED-CAPACITY GAS-HOLDERS; FILLING VESSELS WITH, OR DISCHARGING FROM VESSELS, COMPRESSED, LIQUEFIED, OR SOLIDIFIED GASES
    • F17C13/00Details of vessels or of the filling or discharging of vessels
    • F17C13/12Arrangements or mounting of devices for preventing or minimising the effect of explosion ; Other safety measures
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F17STORING OR DISTRIBUTING GASES OR LIQUIDS
    • F17CVESSELS FOR CONTAINING OR STORING COMPRESSED, LIQUEFIED OR SOLIDIFIED GASES; FIXED-CAPACITY GAS-HOLDERS; FILLING VESSELS WITH, OR DISCHARGING FROM VESSELS, COMPRESSED, LIQUEFIED, OR SOLIDIFIED GASES
    • F17C7/00Methods or apparatus for discharging liquefied, solidified, or compressed gases from pressure vessels, not covered by another subclass
    • F17C7/02Discharging liquefied gases
    • F17C7/04Discharging liquefied gases with change of state, e.g. vaporisation
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F17STORING OR DISTRIBUTING GASES OR LIQUIDS
    • F17CVESSELS FOR CONTAINING OR STORING COMPRESSED, LIQUEFIED OR SOLIDIFIED GASES; FIXED-CAPACITY GAS-HOLDERS; FILLING VESSELS WITH, OR DISCHARGING FROM VESSELS, COMPRESSED, LIQUEFIED, OR SOLIDIFIED GASES
    • F17C2205/00Vessel construction, in particular mounting arrangements, attachments or identifications means
    • F17C2205/03Fluid connections, filters, valves, closure means or other attachments
    • F17C2205/0302Fittings, valves, filters, or components in connection with the gas storage device
    • F17C2205/0323Valves
    • F17C2205/0335Check-valves or non-return valves
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F17STORING OR DISTRIBUTING GASES OR LIQUIDS
    • F17CVESSELS FOR CONTAINING OR STORING COMPRESSED, LIQUEFIED OR SOLIDIFIED GASES; FIXED-CAPACITY GAS-HOLDERS; FILLING VESSELS WITH, OR DISCHARGING FROM VESSELS, COMPRESSED, LIQUEFIED, OR SOLIDIFIED GASES
    • F17C2205/00Vessel construction, in particular mounting arrangements, attachments or identifications means
    • F17C2205/03Fluid connections, filters, valves, closure means or other attachments
    • F17C2205/0302Fittings, valves, filters, or components in connection with the gas storage device
    • F17C2205/0338Pressure regulators
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F17STORING OR DISTRIBUTING GASES OR LIQUIDS
    • F17CVESSELS FOR CONTAINING OR STORING COMPRESSED, LIQUEFIED OR SOLIDIFIED GASES; FIXED-CAPACITY GAS-HOLDERS; FILLING VESSELS WITH, OR DISCHARGING FROM VESSELS, COMPRESSED, LIQUEFIED, OR SOLIDIFIED GASES
    • F17C2223/00Handled fluid before transfer, i.e. state of fluid when stored in the vessel or before transfer from the vessel
    • F17C2223/01Handled fluid before transfer, i.e. state of fluid when stored in the vessel or before transfer from the vessel characterised by the phase
    • F17C2223/0107Single phase
    • F17C2223/0123Single phase gaseous, e.g. CNG, GNC
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F17STORING OR DISTRIBUTING GASES OR LIQUIDS
    • F17CVESSELS FOR CONTAINING OR STORING COMPRESSED, LIQUEFIED OR SOLIDIFIED GASES; FIXED-CAPACITY GAS-HOLDERS; FILLING VESSELS WITH, OR DISCHARGING FROM VESSELS, COMPRESSED, LIQUEFIED, OR SOLIDIFIED GASES
    • F17C2250/00Accessories; Control means; Indicating, measuring or monitoring of parameters
    • F17C2250/04Indicating or measuring of parameters as input values
    • F17C2250/0404Parameters indicated or measured
    • F17C2250/043Pressure
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F17STORING OR DISTRIBUTING GASES OR LIQUIDS
    • F17CVESSELS FOR CONTAINING OR STORING COMPRESSED, LIQUEFIED OR SOLIDIFIED GASES; FIXED-CAPACITY GAS-HOLDERS; FILLING VESSELS WITH, OR DISCHARGING FROM VESSELS, COMPRESSED, LIQUEFIED, OR SOLIDIFIED GASES
    • F17C2260/00Purposes of gas storage and gas handling
    • F17C2260/03Dealing with losses
    • F17C2260/035Dealing with losses of fluid
    • F17C2260/036Avoiding leaks
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F17STORING OR DISTRIBUTING GASES OR LIQUIDS
    • F17CVESSELS FOR CONTAINING OR STORING COMPRESSED, LIQUEFIED OR SOLIDIFIED GASES; FIXED-CAPACITY GAS-HOLDERS; FILLING VESSELS WITH, OR DISCHARGING FROM VESSELS, COMPRESSED, LIQUEFIED, OR SOLIDIFIED GASES
    • F17C2260/00Purposes of gas storage and gas handling
    • F17C2260/04Reducing risks and environmental impact
    • F17C2260/042Reducing risk of explosion
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F17STORING OR DISTRIBUTING GASES OR LIQUIDS
    • F17CVESSELS FOR CONTAINING OR STORING COMPRESSED, LIQUEFIED OR SOLIDIFIED GASES; FIXED-CAPACITY GAS-HOLDERS; FILLING VESSELS WITH, OR DISCHARGING FROM VESSELS, COMPRESSED, LIQUEFIED, OR SOLIDIFIED GASES
    • F17C2270/00Applications
    • F17C2270/05Applications for industrial use
    • F17C2270/0518Semiconductors
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10TTECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T137/00Fluid handling
    • Y10T137/8593Systems
    • Y10T137/85978With pump
    • Y10T137/86083Vacuum pump

Definitions

  • This invention relates to gas containment systems and, more particularly to systems which contain and preferably also abate gases which are accidentally released from apparatus due to, for example, component failure.
  • the gases tend to be supplied to the semi conductor processing apparatus at elevated pressures either from a cylinder of pressurised gas or distributed from a bulk storage system for the gas. In both cases, the supply of gas to the apparatus at the pressures required therein is governed by a gas pressure regulator. Problems arise, however, in the event of failure of the pressure regulator or of other components present in the gas supply system.
  • the gas regulators themselves, they commonly incorporate a diaphragm on one side of which is a reference pressure, for example atmospheric, and on the other side is set the pressure required in the processing apparatus.
  • the gas In the event of failure, for example rupture of the diaphragm, the gas is released at high pressure in the reference pressure side of the regulator and leaks to the atmosphere and can cause environmental damage or, in the case of pyrophoric gases, a fire.
  • the invention is concerned with the provision of a gas containment system which can generally overcome such problems.
  • a gas containment system containing a source of high pressure gas and means to regulate the supply of the gas to processing apparatus, wherein in the event of failure of the regulatory means, means are provided to direct gas escaping from the regulatory means in to a chamber at sub-atmospheric pressure.
  • the regulatory means includes or comprises a gas pressure regulator.
  • the gas directing means is connected to the reference pressure side of the gas pressure regulator.
  • the gas directing means from more than one gas containment system is connected to one chamber at sub-atmospheric pressure.
  • a non-return valve is advantageously present between the regulatory means and the chamber. This is particularly advantageous when the gas directing means from more than one gas containment system is connected to a single chamber. In such cases, it is preferred for there to be a non-return valve for each gas containment system so that in the event of failure of, for example, a diaphragm in one of the containment systems, the reference pressure and hence the continued operability of the remaining undamaged gas containment systems will be unaffected.
  • any pressure regulators in particular present in the gas containment system will be connected to a sub-atmospheric pressure, there will be a need to re-set the delivery set point pressure of the regulator to allow for the off-set pressure being altered. For example, adding 1 bar to the delivery (demand) pressure will return the actual delivered pressure to the original effective operational pressure.
  • the chamber of the gas containment system is preferably evacuated to sub-atmospheric pressure by means of a vacuum pump.
  • a pressure monitor in or otherwise associated with the chamber is advantageously provided to detect a failure in the regulatory means by measuring the resulting rise in pressure in the chamber.
  • a gas containment system which comprises a source of high pressure gas in the form of a cylinder 1 linked by a pipe 2 to a gas pressure regulator 3.
  • the regulator 3 has a diaphragm 4 separating a supply pressure chamber 5 from a reference pressure chamber 6.
  • the reference pressure chamber 6 of the regulator 3 is linked by pipes 7, 8 and 9 to a chamber 10 which is designed to be evacuated to sub-atmospheric pressures by means of a vacuum pump 11 linked to the chamber by means of a pipe 12.
  • a valve 13 is provided to isolate the chamber 10 from the vacuum pump 11.
  • the exhaust side of the vacuum pump 11 is liked to an abatement device 14 in to which the gases directed from the chamber 10 can be rendered environmentally acceptable.
  • Further pipes 15, 16, 17 are also shown which respectively link three further pressure regulators (not shown) similar to the regulator 3 to the pipe 8.
  • Each of the regulators 3, 15, 16, 17 may have their own independent sources of pressurised gas or may be connected to a pressurised bulk storage gas system.
  • a non-return (or check) valve 18 is present in the pipe 7 to prevent any back flow of gas towards the regulator 3. Similar non-return (or check) valves 19, 20, 21 are present in the pipes 15, 16 and 17 respectively.
  • non-return valves The benefit of the pressure of such non-return valves is primarily in a system with more than one gas regulator when failure of one regulator, and a consequent flow of gas through the corresponding non-return valve, will not affect the reference pressure in the other regulators by virtue of the presence of the non-return valves.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Filling Or Discharging Of Gas Storage Vessels (AREA)
  • Apparatus Associated With Microorganisms And Enzymes (AREA)
  • Structure Of Emergency Protection For Nuclear Reactors (AREA)
  • Feeding, Discharge, Calcimining, Fusing, And Gas-Generation Devices (AREA)

Abstract

A gas containment system comprising a source of high pressure gas and means to regulate the supply of the gas to processing apparatus, wherein in the event of failure of the regulatory means, means are provided to direct gas escaping from the regulatory means in to a chamber at sub-atmospheric pressure.

Description

This invention relates to gas containment systems and, more particularly to systems which contain and preferably also abate gases which are accidentally released from apparatus due to, for example, component failure.
In the manufacture of semi conductor devices, numerous gases are employed for the manufacturing processes themselves and for the cleansing/conditioning of the apparatus in which the processing of the semi conductor devices take place. Many of these gases are dangerous in terms of their being toxic or pyrophoric.
The gases tend to be supplied to the semi conductor processing apparatus at elevated pressures either from a cylinder of pressurised gas or distributed from a bulk storage system for the gas. In both cases, the supply of gas to the apparatus at the pressures required therein is governed by a gas pressure regulator. Problems arise, however, in the event of failure of the pressure regulator or of other components present in the gas supply system.
In the case of the gas regulators themselves, they commonly incorporate a diaphragm on one side of which is a reference pressure, for example atmospheric, and on the other side is set the pressure required in the processing apparatus.
In the event of failure, for example rupture of the diaphragm, the gas is released at high pressure in the reference pressure side of the regulator and leaks to the atmosphere and can cause environmental damage or, in the case of pyrophoric gases, a fire.
It is common practice in the event of failure to vent the reference pressure side of the pressure regulator in to a duct to take the gas away from the working areas of the apparatus. However, such venting does not remove the problem of environmental: pollution and/or fire.
The invention is concerned with the provision of a gas containment system which can generally overcome such problems.
In accordance with the invention, there is provided a gas containment system containing a source of high pressure gas and means to regulate the supply of the gas to processing apparatus, wherein in the event of failure of the regulatory means, means are provided to direct gas escaping from the regulatory means in to a chamber at sub-atmospheric pressure.
Preferably, the regulatory means includes or comprises a gas pressure regulator. In such embodiments, the gas directing means is connected to the reference pressure side of the gas pressure regulator.
In preferred embodiments, the gas directing means from more than one gas containment system is connected to one chamber at sub-atmospheric pressure.
A non-return valve is advantageously present between the regulatory means and the chamber. This is particularly advantageous when the gas directing means from more than one gas containment system is connected to a single chamber. In such cases, it is preferred for there to be a non-return valve for each gas containment system so that in the event of failure of, for example, a diaphragm in one of the containment systems, the reference pressure and hence the continued operability of the remaining undamaged gas containment systems will be unaffected.
It is to be noted that, as the reference pressure side of any pressure regulators in particular present in the gas containment system will be connected to a sub-atmospheric pressure, there will be a need to re-set the delivery set point pressure of the regulator to allow for the off-set pressure being altered. For example, adding 1 bar to the delivery (demand) pressure will return the actual delivered pressure to the original effective operational pressure.
The chamber of the gas containment system is preferably evacuated to sub-atmospheric pressure by means of a vacuum pump.
A pressure monitor in or otherwise associated with the chamber is advantageously provided to detect a failure in the regulatory means by measuring the resulting rise in pressure in the chamber.
Having collected any gas escaping through the gas containment system of the invention, there will generally be a need to abate the toxicity and/or flammability of the gases in situ in the chamber or, preferably, by directing the gas by means of its own inherent pressure and/or by means of a vacuum pump attached downstream of the chamber in to an abatement device in which the gases may be rendered harmless and made suitable for release to the atmosphere.
For a better understanding of the invention, reference will now be made to the accompanying drawing showing a schematic representation of a gas containment system of the invention.
With reference to the drawing, there is shown a gas containment system which comprises a source of high pressure gas in the form of a cylinder 1 linked by a pipe 2 to a gas pressure regulator 3. The regulator 3 has a diaphragm 4 separating a supply pressure chamber 5 from a reference pressure chamber 6.
The reference pressure chamber 6 of the regulator 3 is linked by pipes 7, 8 and 9 to a chamber 10 which is designed to be evacuated to sub-atmospheric pressures by means of a vacuum pump 11 linked to the chamber by means of a pipe 12. A valve 13 is provided to isolate the chamber 10 from the vacuum pump 11.
The exhaust side of the vacuum pump 11 is liked to an abatement device 14 in to which the gases directed from the chamber 10 can be rendered environmentally acceptable.
Further pipes 15, 16, 17 are also shown which respectively link three further pressure regulators (not shown) similar to the regulator 3 to the pipe 8. Each of the regulators 3, 15, 16, 17 may have their own independent sources of pressurised gas or may be connected to a pressurised bulk storage gas system.
A non-return (or check) valve 18 is present in the pipe 7 to prevent any back flow of gas towards the regulator 3. Similar non-return (or check) valves 19, 20, 21 are present in the pipes 15, 16 and 17 respectively.
The benefit of the pressure of such non-return valves is primarily in a system with more than one gas regulator when failure of one regulator, and a consequent flow of gas through the corresponding non-return valve, will not affect the reference pressure in the other regulators by virtue of the presence of the non-return valves.

Claims (8)

  1. A gas containment system comprising a source of high pressure gas and means to regulate the supply of the gas to processing apparatus, wherein in the event of failure of the regulatory means, means are provided to direct gas escaping from the regulatory means in to a chamber at sub-atmospheric pressure.
  2. A system as claimed in Claim 1 in which the regulatory means includes or comprises a gas pressure regulator.
  3. A system according to Claim 2 in which the gas directing means is connected to the reference pressure side of the gas pressure regulator.
  4. A system according to any preceding claim in which gas directing means from more than one gas containment system is connected to one chamber at sub-atmospheric pressure.
  5. A system according to any preceding claim in which a non-return valve is present between the regulatory means and the chamber.
  6. A system according to any preceding claim in which the chamber is evacuated to sub-atmospheric pressure by means of a vacuum pump.
  7. A system according to any preceding claim in which a pressure monitor associated with the chamber is provided to detect a failure in the regulatory means.
  8. A system according to any preceding claim in which gas in the chamber is directed to an abatement device.
EP02253134A 2001-05-09 2002-05-03 Gas containment system Withdrawn EP1258670A3 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GBGB0111417.2A GB0111417D0 (en) 2001-05-09 2001-05-09 Gas containment system
GB0111417 2001-05-09

Publications (2)

Publication Number Publication Date
EP1258670A2 true EP1258670A2 (en) 2002-11-20
EP1258670A3 EP1258670A3 (en) 2005-06-15

Family

ID=9914370

Family Applications (1)

Application Number Title Priority Date Filing Date
EP02253134A Withdrawn EP1258670A3 (en) 2001-05-09 2002-05-03 Gas containment system

Country Status (4)

Country Link
US (1) US20020179156A1 (en)
EP (1) EP1258670A3 (en)
JP (1) JP2003049998A (en)
GB (1) GB0111417D0 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2012034979A3 (en) * 2010-09-16 2012-05-10 Solvay Sa Hydrogen fluoride supply unit
CN105546340A (en) * 2015-12-10 2016-05-04 马鞍山钢铁股份有限公司 Method and device for preventing moisture leakage of air separation vaporization system

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
TW201530041A (en) * 2013-10-11 2015-08-01 Applied Materials Inc Compact hazardous gas line distribution enabling system single point connections for multiple chambers
US20180119888A1 (en) * 2015-05-12 2018-05-03 Entegris, Inc. Valve assemblies and fluid storage and dispensing packages comprising same

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4010769A (en) * 1972-11-27 1977-03-08 Plast-O-Matic Valves, Inc. Leak detection arrangement for valve having sealing means
US5392636A (en) * 1992-12-30 1995-02-28 Blackwell; Robert S. Apparatus and method for leak testing pressure regulated LPG systems
US5967173A (en) * 1997-07-14 1999-10-19 Furon Corporation Diaphragm valve with leak detection

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2012034979A3 (en) * 2010-09-16 2012-05-10 Solvay Sa Hydrogen fluoride supply unit
CN103154594A (en) * 2010-09-16 2013-06-12 索尔维公司 Hydrogen fluoride supply unit
US9334574B2 (en) 2010-09-16 2016-05-10 Solvay Sa Hydrogen fluoride supply unit
CN105546340A (en) * 2015-12-10 2016-05-04 马鞍山钢铁股份有限公司 Method and device for preventing moisture leakage of air separation vaporization system

Also Published As

Publication number Publication date
GB0111417D0 (en) 2001-07-04
JP2003049998A (en) 2003-02-21
US20020179156A1 (en) 2002-12-05
EP1258670A3 (en) 2005-06-15

Similar Documents

Publication Publication Date Title
US5417236A (en) Automated process gas supply system for evacuating a process line
CN106310553A (en) High-pressure air supply system for safety refuge system and working method of high-pressure air supply system
EP1258670A2 (en) Gas containment system
US7353881B2 (en) Ganged fire extinguisher system
US20240353064A1 (en) Method and an apparatus for preventing the emission of harmful gases into atmosphere
US20230259147A1 (en) Multi-stage gas pressure reduction system
CN101868667A (en) Small-sized gas holder
US5344313A (en) Fugitive volatile organic compound vapor collection system
WO2010034602A1 (en) Pressure-resistant component having a sealed joint
DE59601674D1 (en) METHOD AND DEVICE FOR FAST PRESSURE RELEASE IN A PLANT, IN PARTICULAR WITH A HYDROGEN-COOLED GENERATOR
US6969229B2 (en) Sealing system for centrifugal compressors which process lethal gases
US20110212677A1 (en) Housing assembly for an electrical device
GB8413203D0 (en) Manifolding systems for gas containers
CN208706593U (en) A vacuum pipeline protection system
CN210814326U (en) Air source processing device
US20240287953A1 (en) Instrument gas capture system
US6729145B1 (en) Process plant
US12071871B1 (en) Positive pressure air cleaning apparatus for a crankcase ventilation system
CA3061854A1 (en) Method and apparatus for recovering vented volumes of gas into containment
CN213893807U (en) A self-protection device for atmospheric storage tanks after nitrogen seals and safety accessories fail
CA2143918C (en) Method and apparatus for reducing damper operating pressure
EP2865424A1 (en) Air compressor system
CN209782979U (en) Oil gas recovery device
SA122440803B1 (en) Integrated ignition system with gas unit
SU1032267A2 (en) Drainage pipeline protecting device

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A2

Designated state(s): AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE TR

AX Request for extension of the european patent

Free format text: AL;LT;LV;MK;RO;SI

PUAL Search report despatched

Free format text: ORIGINAL CODE: 0009013

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

AK Designated contracting states

Kind code of ref document: A3

Designated state(s): AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE TR

AX Request for extension of the european patent

Extension state: AL LT LV MK RO SI

RIC1 Information provided on ipc code assigned before grant

Ipc: 7F 17C 13/12 B

Ipc: 7F 17C 7/00 A

18D Application deemed to be withdrawn

Effective date: 20041201