EP2957719A1 - Rotoreinheit für eine Turbomaschine und Verfahren zu deren Konstruktion - Google Patents

Rotoreinheit für eine Turbomaschine und Verfahren zu deren Konstruktion Download PDF

Info

Publication number
EP2957719A1
EP2957719A1 EP14172598.6A EP14172598A EP2957719A1 EP 2957719 A1 EP2957719 A1 EP 2957719A1 EP 14172598 A EP14172598 A EP 14172598A EP 2957719 A1 EP2957719 A1 EP 2957719A1
Authority
EP
European Patent Office
Prior art keywords
module
blades
rotor unit
hub
axial shaft
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Withdrawn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
EP14172598.6A
Other languages
English (en)
French (fr)
Inventor
Shadab Ali
Deepak Malik
Prashant Shukla
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.)
Siemens AG
Original Assignee
Siemens AG
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 Siemens AG filed Critical Siemens AG
Priority to EP14172598.6A priority Critical patent/EP2957719A1/de
Publication of EP2957719A1 publication Critical patent/EP2957719A1/de
Withdrawn legal-status Critical Current

Links

Images

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
    • F01D5/00—Blades; Blade-carrying members; Heating, heat-insulating, cooling or antivibration means on the blades or the members
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
    • F01D5/00—Blades; Blade-carrying members; Heating, heat-insulating, cooling or antivibration means on the blades or the members
    • F01D5/02—Blade-carrying members, e.g. rotors
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
    • F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
    • F05D2230/00—Manufacture
    • F05D2230/10—Manufacture by removing material
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
    • F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
    • F05D2230/00—Manufacture
    • F05D2230/20—Manufacture essentially without removing material
    • F05D2230/21—Manufacture essentially without removing material by casting
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
    • F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
    • F05D2230/00—Manufacture
    • F05D2230/20—Manufacture essentially without removing material
    • F05D2230/22—Manufacture essentially without removing material by sintering
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
    • F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
    • F05D2230/00—Manufacture
    • F05D2230/20—Manufacture essentially without removing material
    • F05D2230/25—Manufacture essentially without removing material by forging

Definitions

  • the present invention relates to a rotor unit for a turbomachine comprising a blade module comprising a hub and a plurality of blades, wherein the plurality of blades is disposed on the hub and an axial shaft module, wherein the axial shaft module is connected to the blade module.
  • the present invention also relates to a method for construction of a rotor unit for a turbomachine wherein the rotor unit is provided with a blade module comprising a hub and a plurality of blades and an axial shaft module.
  • a turbomachine is a rotary mechanical device wherein mechanical energy from a fluid flow is converted into electric power by means of a generator comprised in the turbomachine.
  • turbomachines include steam turbines, gas turbines, et cetera.
  • the turbomachine comprises a moving part termed as a rotor and a stationary part termed as a stator.
  • the rotor in turn consists of an axial shaft whereon a multitude of blades is disposed.
  • the rotor unit comprises a plurality of stages, wherein the stages are arranged contiguously in an axial direction. Each stage of the rotor comprises a portion of the axial shaft whereon a plurality of blades is disposed in a circumferential direction. Therefore, an assembly of blades for the turbomachine extends both axially and circumferentially.
  • the number of blades comprised in a certain stage, and/or the number of stages comprised in the rotor for the turbomachine depends on the design of the turbomachine, application of the turbomachine, and the intended power output of the turbomachine.
  • the moving fluid however acts on the blades, imparts rotational energy to the rotor, thereby enabling the generation of power.
  • each of the blades for respective rotor units is individually assembled and coupled to the respective axial shaft portion.
  • Each blade is provided with a root portion shaped as a fir-tree serration, T-root joint, fork root, et cetera, for the purpose of affixing the blade to the axial shaft portion.
  • the axial shaft portion is provided with a complementary space, which is profiled to accommodate the root portion of the blade.
  • the blade is coupled to the axial shaft portion using any of the well-known coupling techniques, such as flanges, tie bolts, rivets, welding, brazing, et cetera.
  • other blades are disposed in a similar manner, in order to obtain a certain stage of the rotor.
  • the aforementioned assembly of the rotor unit leads to stress concentrations in those specific root fixity regions, where the rotor and blade are coupled to each other.
  • the stress concentrations can lead to potential failures in the form of cracks, blade dislodgement, undesired blade vibrations (which are caused due to loosening of the blades), rotor stability, et cetera, during the operation of the turbomachine.
  • the blades are always prone to fretting at the root portions due to a discontinuous profile at the blade root-shaft interface. This increases the possibility of blade loosening and eventual dislodgement during the operation of the turbomachine, and such occurrences can hamper the operation of the turbomachine, thereby leading to equipment losses and shutting down of the turbomachine.
  • the object of the present invention is to provide a rotor unit of the aforementioned kind which has a stable and a simple design.
  • the aforementioned objective is achieved as the plurality of blades and the hub that are integral to each other.
  • a rotor unit for a turbomachine comprises a blade module and an axial shaft module, which are connected with each other.
  • the blade module and the axial shaft module are connected such that proper rotary operation of the rotor unit is enabled, i.e. the connecting force between the blade module and the axial shaft module is greater than the rotational forces experienced by the rotor unit during the operation of the turbomachine.
  • the blade module comprises a plurality of blades and a hub, where the plurality of blades and the hub are integral to each other.
  • the blade module can comprise any number of blades, for example, eight blades, sixteen blades, twenty blades, et cetera.
  • the plurality of blades is not capable of being dismantled as a separate part from the hub under normal operating conditions, because the plurality of blades and the hub are integral to each other. Since the plurality of the blades and the hub are integral to each other, the rotor unit has considerable strength benefits in comparison with the blades held individually with a rotor by root serrations. In this way, stress concentrations and fretting at the root of the blades is prevented due to the integral nature of the plurality of blades and the hub.
  • a material of the plurality of blades is identical to a material of the hub. Since the materials are identical, the mechanical coupling of the plurality of blades and the hub is further enhanced, leading to an increased robustness of the blade module. Therewith, a homogenous blade module is obtained, which is capable of being manufactured easily, and such a blade module also offers enhanced resistance against thermal stresses.
  • the hub is annular.
  • the plurality of blades is annularly disposed on the hub.
  • Popular time-saving and efficient machining techniques such as 360° machining techniques can be applied advantageously, in order to obtain the annular hub and the annular disposition of the blades.
  • the blade module further comprises a support rim.
  • the support rim extends in an axial as well as in the circumferential direction, and is further arranged to contact the axial shaft module.
  • the support rim is beneficial for increasing the area of coupling between the axial shaft module and the blade module.
  • the support rim is an axial and a circumferential extension of the hub.
  • the support rim also extends in accordance with a contour of the hub.
  • the area of coupling comprises inner surfaces of the support rim and the hub, and the outer surface of the axial shaft module.
  • a frictional force between the blade module and the axial shaft module is increasable, wherewith an enhanced coupling strength is achievable, which is beneficial in preventing the slippage between the blade module and the axial shaft module during the operation of the rotor unit.
  • An increased area of coupling provides enhanced coupling strength to the blade module and the axial shaft module.
  • the support rim is integral to the hub.
  • greater strength and sturdiness of the blade module are achieved.
  • techniques such as shrink-fitting can be employed to clamp the blade module to the axial shaft module, which increases the simplicity of production of the rotor units.
  • the hub comprises a cooling channel.
  • a coolant fluid is dispensable into the cooling channel during an operation of the rotor unit for cooling the plurality of the blades. This is beneficial in keeping the rotor unit at an optimal temperature during the operation of the rotor unit. Therewith, any malfunctioning arising out of overheating of the blade module can be avoided.
  • the object of the invention is solved by manufacturing the blade module, such that the plurality of blades is disposed on the hub, and wherein the plurality of blades and the hub are integral to each other.
  • the blade module and the axial shaft module are connected to each other. Since the plurality of the blades and the hub are manufactured such that the plurality of the blades and the hub are integral to each other, the strength of the rotor unit is enhanced as compared to a rotor unit comprising the blades, wherein the blades are held individually on a shaft using root serrations. Thus, stress concentrations and fretting at the root of the blades are prevented due to the integral nature of the plurality of blades and the hub.
  • the blade module is shrink-fitted onto the axial shaft module.
  • Shrink fitting is a simple and a cost-effective mechanical process of manufacturing the rotor unit. Furthermore, it is beneficial for reducing the production time for the rotor unit.
  • the blade module is fabricated monolithically. This is beneficial for obtaining a homogenous blade module, which offers enhanced resistance against thermal stresses.
  • the monolithic fabrication of the blade module is achieved by any of the processes such as casting, laser sintering, moulding, machining, Electrical Discharge Machining, forging, or welding. The aforementioned processes are well-known processes, wherewith the time required for machining and production of such a blade module is considerably reduced.
  • FIG 1 shows an embodiment of the rotor unit 1 according to the invention in a perspective view.
  • the rotor unit 1 is part of a turbomachine (not depicted), such as a gas turbine, a steam turbine, a combined cycle power plant, et cetera.
  • a turbomachine such as a gas turbine, a steam turbine, a combined cycle power plant, et cetera.
  • a blade module 2 and an axial shaft module 3 are comprised in the rotor unit 1.
  • the axial shaft module 3 is a portion of the axial shaft (not depicted) of the said turbomachine.
  • the blade module 2 is disposed on the axial shaft module 3.
  • the axial shaft module 3 has a diameter 'd S ', and the axial shaft module 3 extends along a longitudinal axis 100 of the turbomachine.
  • the longitudinal axis 100 is 'a rotational axis' of the turbomachine.
  • the blade module 2 and the axial shaft module 3 are further connected together for enabling the operation of the rotor unit 1.
  • the rotor unit 1 rotates along a circumferential direction 120 during the operation of the turbomachine.
  • the blade module 2 comprises a plurality of blades 4, a hub 5 and a support rim 6.
  • the hub 5 is annular, and the plurality of blades 4 is annularly disposed on the hub 5.
  • Each of the plurality of blades 4 extends both axially and radially.
  • the support rim 6 is a part of the hub 5, and the support rim 6 extends both circumferentially and axially.
  • the support rim 6 is present in a coupling region, i.e.
  • the region where the blade module 2 and the axial shaft module 3 are connected to each other, and the support rim 6 is beneficial as this increases the surface area of contact between the blade module 2 and the axial shaft module 3 which in turn leads to an increased area of coupling, wherewith a tight coupling between the blade module 2 and the axial shaft module 3 is achievable.
  • FIG 2 depicts an exemplary monolithic fabrication process for the blade module 2.
  • FIG 1 is also referred to herein for the purpose of elucidation of FIG 2 .
  • the blade module 2 is fabricated from an annular ring 7, and the annular ring 7 is a monolithic component.
  • the annular ring 7 is provided as an input to a machining system 20, and the blade module 2 is obtained as an output of the machining system 20.
  • the annular ring 7 has an inner diameter 'd B1 ' and an outer diameter of 'D 0 '.
  • the annular ring 7 preferably comprises two concentric regions, viz. a first region 8 and a second region 9, which are capable of being machined to form the blade module 2.
  • the second region 9 surrounds the first region 8.
  • the machining system 20 is configured to machine the annular ring 7 such that the plurality of blades 4 is machined out of the second region 9, and the hub is machined out of the first region, in order to obtain the integrated blade module 2.
  • the integral aspect of the blade module 2 is noticeable in FIG 3 and elucidated therein.
  • the support rim 6 is also obtained by machining the first region 8.
  • the machining system 20 is a 360° machining tool such as a lathe, which is well known in the art.
  • other machining tools and techniques may be used for the purpose of machining the annular ring 7 for the purpose of obtainment of the blade module 2.
  • the inner diameter of the blade module 2 is also 'd B1 '.
  • the annular ring 7 preferably consists of a single material, which can be for example, a metal, an alloy, or a composite material. Therefore, the hub 5 and the plurality of blades 4, which are obtained after machining the annular ring 7, are also made of the same material.
  • the monolithic fabrication of the blade module 2 can also be achieved by other well-known techniques, such as die-casting, laser sintering, moulding, Electrical Discharge Machining, forging and welding, etc.
  • FIG 3 depicts a cross-sectional view of the blade module 2 along a section III-III as depicted in FIG 2 .
  • FIG 3 A view shown in FIG 3 is of a pair of antipodal blades which is integral to the hub 5.
  • the fabrication of the blade module 2 is such that root portions 11 of the respective blades are integrated into the hub 5, which in turn increases the robustness, and strength of the blade module 2. Furthermore, the probability of dislodgement of a certain blade during the operation of the rotor unit 1 is reduced further, thereby increasing the stability of the rotor unit 1.
  • the hub 5 also comprises a cooling channel 10, wherein the cooling channel 10 extends circumferentially along the hub 5. Furthermore, the cooling channel 10 is located internal to the hub 5, and the cooling channel 10 is also located proximal to the root portions 11 of the plurality of blades 4. A coolant fluid may be circulated within the cooling channel 10 for cooling the blade module 2, especially the root portions 11 of the plurality of blades 4, during the operation of the rotor unit 1.
  • FIG 4 depicts a flowchart 40 for a method for construction of the rotor unit 1.
  • the blade module 2 is manufactured from the annular ring 7.
  • the annular ring 7 is 360°-machined to obtain the plurality of blades 4 and the hub 5.
  • the annular ring 7 is 360°-machined, such that plurality of blades 4 is integrally disposed on the hub 5, wherewith the plurality of blades 4 and the hub 5 form a monolithic component.
  • the annular ring 7 is 360°-machined by techniques, such as die-casting, laser sintering, moulding, Electrical Discharge Machining, forging and welding, etc.
  • the axial shaft module 3 is provided.
  • the blade module 2 and the axial shaft module 3 are connected to each other.
  • the blade module 2 and the axial shaft module 3 are connected to each other by an exemplary shrink fitting process. An overview of the shrink fitting process is elucidated with reference to FIGS 5a and 5b .
  • FIG 5a which depicts an intermediate step of the shrink-fitting process
  • the blade module 2 is heated along the hub 5, such that the inner diameter of the blade module 2 is increased to d B2 (i.e. d B2 > d B1 ).
  • the diameter 'd S ' of the axial shaft module 3 however remains a constant.
  • the axial shaft module 3 and the blade module 2 are then arranged, such that the blade module 2 (with the increased diameter d B2 ) is annularly disposed on the axial shaft module 3.
  • the blade module 2 is then coupled with the axial shaft module 3 at a user-desired region and the blade module 2 is subsequently cooled to achieve a tight fit.
  • the blade module 2 is clamped on to the axial shaft module 3.
  • This figure depicts a final step of the shrink-fitting process, the blade module 2 is cooled, such that the inner diameter of the blade module 2 is reduced to d B3 , wherein d B2 > d B3 > d B1 .
  • the final inner diameter d B3 of the blade module 2 is however marginally greater than the diameter d S of the axial shaft module 3.
  • the shrink fittable attribute of the blade module 2 increases the robustness of the rotor unit 1, because the strength of coupling between the axial shaft module 3 and the blade module 2 is enhanced.
  • the blade module 2 and the axial shaft module 3 are made of the same material, wherewith the strength of coupling between the blade module 2 and the axial shaft module 3 is increased after the shrink-fitting process.
  • the blade module 2 and the axial shaft module 3 can be connected to each other by welding also.
  • the blade module 2 and the axial shaft module 3 can also be made of different materials.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Structures Of Non-Positive Displacement Pumps (AREA)
EP14172598.6A 2014-06-16 2014-06-16 Rotoreinheit für eine Turbomaschine und Verfahren zu deren Konstruktion Withdrawn EP2957719A1 (de)

Priority Applications (1)

Application Number Priority Date Filing Date Title
EP14172598.6A EP2957719A1 (de) 2014-06-16 2014-06-16 Rotoreinheit für eine Turbomaschine und Verfahren zu deren Konstruktion

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP14172598.6A EP2957719A1 (de) 2014-06-16 2014-06-16 Rotoreinheit für eine Turbomaschine und Verfahren zu deren Konstruktion

Publications (1)

Publication Number Publication Date
EP2957719A1 true EP2957719A1 (de) 2015-12-23

Family

ID=50942171

Family Applications (1)

Application Number Title Priority Date Filing Date
EP14172598.6A Withdrawn EP2957719A1 (de) 2014-06-16 2014-06-16 Rotoreinheit für eine Turbomaschine und Verfahren zu deren Konstruktion

Country Status (1)

Country Link
EP (1) EP2957719A1 (de)

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6269540B1 (en) * 1998-10-05 2001-08-07 National Research Council Of Canada Process for manufacturing or repairing turbine engine or compressor components
WO2007095902A1 (de) * 2006-02-25 2007-08-30 Mtu Aero Engines Gmbh Verfahren zur herstellung und reparatur eines integral beschaufelten rotors
FR2901305A1 (fr) * 2006-05-18 2007-11-23 Snecma Sa Disque de turbine monobloc
DE102007050142A1 (de) * 2007-10-19 2009-04-23 Mtu Aero Engines Gmbh Verfahren zur Herstellung einer Blisk oder eines Blings, damit hergestelltes Bauteil und Turbinenschaufel
DE102008057160A1 (de) * 2008-11-13 2010-05-20 Mtu Aero Engines Gmbh Verfahren zum Austausch eines inneren Scheibenelements einer integral beschaufelten Scheibe
EP2650474A2 (de) * 2012-04-11 2013-10-16 Honeywell International Inc. Axial geteilte Radialturbinen und Verfahren zu ihrer Herstellung

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6269540B1 (en) * 1998-10-05 2001-08-07 National Research Council Of Canada Process for manufacturing or repairing turbine engine or compressor components
WO2007095902A1 (de) * 2006-02-25 2007-08-30 Mtu Aero Engines Gmbh Verfahren zur herstellung und reparatur eines integral beschaufelten rotors
FR2901305A1 (fr) * 2006-05-18 2007-11-23 Snecma Sa Disque de turbine monobloc
DE102007050142A1 (de) * 2007-10-19 2009-04-23 Mtu Aero Engines Gmbh Verfahren zur Herstellung einer Blisk oder eines Blings, damit hergestelltes Bauteil und Turbinenschaufel
DE102008057160A1 (de) * 2008-11-13 2010-05-20 Mtu Aero Engines Gmbh Verfahren zum Austausch eines inneren Scheibenelements einer integral beschaufelten Scheibe
EP2650474A2 (de) * 2012-04-11 2013-10-16 Honeywell International Inc. Axial geteilte Radialturbinen und Verfahren zu ihrer Herstellung

Similar Documents

Publication Publication Date Title
US20080016688A1 (en) Process for manufacturing a blisk and mold for implementing the process
JP5606489B2 (ja) ターボ機械用ダイヤフラム及びその製造方法
EP2920424B1 (de) Verfahren zur herstellung von schaufeln von turbomaschinen durch drahterodieren, schaufeln und turbomaschinen
JP2007231868A (ja) 蒸気タービン動翼およびそれを用いた蒸気タービン並びに蒸気タービン発電プラント
US20190275575A1 (en) Hydraulic extrusion tool with integrated induction device
US20150098802A1 (en) Shrouded turbine blisk and method of manufacturing same
JP2017526846A (ja) タービンブリスクおよびタービンブリスクを製造する方法
JP6860592B2 (ja) 水力発電機並びにその製造方法およびその運転方法
JP6247682B2 (ja) 静翼ダイヤフラムリング、ターボ機械、および方法
FR3094906B1 (fr) Procede de fabrication d’un element aubage de stator pour une turbomachine et outillage pour sa mise en oeuvre
JP5965622B2 (ja) ピン留め又はボルト留めされた内側リングを備えたマージン段ノズル用の蒸気タービンシングレット接合部
EP2540988A2 (de) Pfropfenanordnung für die Aussendichtung einer Turbinenschaufel
JP6284495B2 (ja) 真空ポンプの為のローター装置の製造の為の方法および真空ポンプの為のローター装置
JP2020084768A (ja) ノズルダイアフラムの製造方法、及びノズルダイアフラム
EP2957719A1 (de) Rotoreinheit für eine Turbomaschine und Verfahren zu deren Konstruktion
US7866949B2 (en) Methods and apparatus for fabricating a rotor for a steam turbine
EP2576998B1 (de) Dampfturbineneinheit und Verfahren zur Montage einer Dampfturbine
EP2955329A1 (de) Integral geformte rotoranordnung mit welle und blisks
JP5751950B2 (ja) ガスタービン及びガスタービンの補修方法
US20180102699A1 (en) Segmented rotor for an asynchronous machine and an asynchronous machine having such a segmented rotor
EP3263851A1 (de) Turbinenanordnung
EP3046228A1 (de) Generatorrotor für einen elektrischen Generator und Verfahren zur Herstellung davon
US9366146B2 (en) Closure bucket for turbo-machine
US11053799B2 (en) Steam turbine rotor
CN113474971A (zh) 具有以增材方法施加的连接元件的复杂的环形元件

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: A1

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

AX Request for extension of the european patent

Extension state: BA ME

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

18D Application deemed to be withdrawn

Effective date: 20160624