Radial lead seal assembly for a generator and a radial lead seal assembly of a generator

Patent metadata

Field	Value
Publication number	US-9593775-B2
Application number	US-201514799985-A
Country	US
Kind code	B2
Filing date	Jul 15, 2015
Priority date	Jul 15, 2015
Publication date	Mar 14, 2017
Grant date	Mar 14, 2017

Abstract

A retrofit method for modifying a radial lead seal assembly of a generator and a radial lead seal assembly of a generator are presented. The radial lead seal assembly seals a radial chamber from an axial chamber. The radial lead seal assembly includes sealing elements disposed around a radial lead to seal an annular space between the radial lead and the radial chamber, a coil spring disposed around the radial lead between the sealing elements and a junction between the radial lead and the axial lead, and a nut. The retrofit method includes removing one or more of the sealing elements to define a radial space between the remainder of the sealing elements and the coil spring. Conical springs are inserted in the radial space and only partially compressed under a radially inward compressive load exerted on the radial lead seal assembly via the nut.

First claim

What is claimed is:

1. A retrofit method for modifying a radial lead seal assembly of a generator, wherein the generator comprises a lead assembly for conducting a field current to a rotor winding, wherein the lead assembly comprises an axial lead extending within an axial chamber through the rotor and a radial lead extending radially outward from the axial lead through a radial chamber, wherein the radial lead seal assembly fluidically seals the radial chamber from the axial chamber, wherein the radial lead seal assembly comprises a plurality of annular sealing elements disposed around the radial lead so as to seal an annular space between the radial lead and the radial chamber, a coil spring disposed annularly around the radial lead between the plurality of sealing elements and a junction between the radial lead and the axial lead, and a loading member, the retrofit method comprising:
removing one or more of the annular sealing elements to define a radial space between the remainder of the sealing elements and the coil spring;
inserting a plurality of conical springs in said radial space; and
applying a radially inward compressive load on the radial lead seal assembly via the loading member such that the conical springs are only partially compressed,
wherein a clearance from an outer diameter of the conical springs to an inner diameter of the radial chamber is smaller than a clearance from an inner diameter of the conical springs to an outer diameter of an insulation of the radial lead so that the conical springs do not contact with an insulated surface of the radial lead.

2. The retrofit method according to claim 1 , wherein a transition spacer is disposed annularly around the radial lead between the coil spring and the conical springs.

3. The retrofit method according to claim 1 , wherein the compressive load exerted by the loading member fully compresses the coil spring.

4. The retrofit method according to claim 1 , wherein the loading member comprises a nut engaged to the radial chamber at a radially outer end of the radial lead, and wherein the compressive load is applied by exerting a torque on the nut.

5. The retrofit method according to claim 1 , wherein the plurality of sealing elements are made of a material comprising neoprene rubber.

6. The retrofit method according to claim 1 , wherein the conical springs are oriented in a series configuration.

7. The retrofit method according to claim 1 , wherein the conical springs are oriented in a parallel configuration.

8. The retrofit method according to claim 1 , wherein the conical springs are oriented in a combination of series and parallel configurations.

9. A radial lead seal assembly of a generator, wherein the generator comprises a lead assembly for conducting a field current to a rotor winding, wherein the lead assembly comprises an axial lead extending within an axial chamber through the rotor and a radial lead extending radially outward from the axial lead through a radial chamber, the radial lead seal assembly comprising:
a plurality of annular sealing elements disposed around the radial lead to seal an annular space between the radial lead and the radial chamber and thereby seal the axial chamber fluidically from the radial chamber;
a coil spring disposed annularly around the radial lead between the plurality of sealing elements and a junction between the radial lead and the axial lead;
a plurality of conical springs disposed annularly around the radial lead in a radial gap between the plurality of sealing elements and the coil spring; and
a loading member for exerting a compressive load on the radial lead seal assembly in radially inward direction such that the conical springs are only partially compressed,
wherein a clearance from an outer diameter of the conical springs to an inner diameter of the radial chamber is smaller than a clearance from an inner diameter of the conical springs to an outer diameter of an insulation of the radial lead so that the conical springs do not contact with an insulated surface of the radial lead.

10. The radial lead seal assembly according to claim 9 , further comprising a transition spacer disposed annularly around the radial lead between the coil spring and the conical springs.

11. The radial lead seal assembly according to claim 9 , wherein the compressive load exerted by the loading member fully compresses the coil spring.

12. The radial lead seal assembly according to claim 9 , wherein the loading member comprises a nut engaged to the radial chamber at a radially outer end of the radial lead, and wherein the compressive load is applied by exerting a torque on the nut.

13. The radial lead seal assembly according to claim 9 , wherein the plurality of sealing elements are made of a material comprising neoprene rubber.

14. The radial lead seal assembly according to claim 9 , wherein the conical springs are oriented in a series configuration.

15. The radial lead seal assembly according to claim 9 , wherein the conical springs are oriented in a parallel configuration.

16. The radial lead seal assembly according to claim 9 , wherein the conical springs are oriented in a combination of series and parallel configurations.

Assignees

• Siemens Energy Inc

Inventors

• Rasinski Michael J
• Gore Robert
• Whitener Randy Edward

Classifications

• F16J15/021 Primary

  with elastic packing (F16J15/08 takes precedence) · CPC title

• H02K15/50

  Disassembling, repairing or modifying dynamo-electric machines (repairing of cooling fluid boxes H02K15/38) · CPC title

• H02K5/124

  Sealing of shafts · CPC title

• H02K3/51 Primary

  applicable to rotors only · CPC title