KF90NY/15F6 Generator AC Seal Oil Pump: Reading Shaft Seal Health From a Drip Pattern

 

 

The KF90NY/15F6 pump handles a job that sounds simple but carries real consequence - pulling lubricating oil out of a storage tank or lube oil reservoir, then pushing it through piping to the generator's seal points, where it lubricates and cools the rotor, stator, and related components. Seal oil systems like this one keep hydrogen contained inside the generator casing while simultaneously protecting rotating parts from friction and heat, a dual purpose that makes pump reliability here genuinely important rather than a minor operational detail.

 

Can mechanical seal leakage on this pump lead to seal oil escaping externally, contaminating the surrounding environment and wasting oil in the process? Yes, and this is actually one of the more common wear-related issues that shows up over a mechanical seal's working life. A mechanical seal relies on two very flat, precisely matched faces pressed together, one rotating with the shaft and one stationary, with a thin fluid film between them providing both lubrication and the actual sealing action. As these faces wear over months and years of continuous operation, that fluid film and the contact between faces changes, and it's common for a small amount of oil to start passing through the seal interface rather than staying fully contained.

 

Left unaddressed, this leakage does exactly what the question describes - oil escapes past the shaft seal, potentially creating a housekeeping and environmental concern around the pump, along with the ongoing cost of replacing lost oil that's supposed to be circulating through the closed seal oil system rather than dripping onto the floor. Beyond the direct waste, persistent leakage around a pump shaft can also point to a seal that's degrading toward a more serious failure, one that could eventually affect the pump's ability to maintain proper pressure and flow to the generator seals themselves.

 

How can drip patterns at the shaft seal actually tell an operator or technician whether the mechanical seal needs replacing? A completely healthy mechanical seal typically shows either no visible leakage at all, or in some designs, an extremely minimal, barely-there weep that's considered normal and doesn't accumulate into actual drips. The real signal worth watching for is a shift away from that baseline. A seal that starts producing a steady, countable drip rate - say, drops forming and falling at a consistent, noticeable pace - where there was previously little to no visible leakage indicates the seal faces have worn enough that they're no longer maintaining a proper fluid film and sealing contact.

 

Tracking this over time matters more than a single observation. A drip rate that's stable and light might warrant continued monitoring rather than immediate action, while a drip rate that's clearly increasing week over week, or that's progressed from an occasional drop to a small but steady stream, signals a seal that's actively degrading and heading toward a more significant failure if left alone. Combining visual drip observation with periodic oil consumption tracking - noticing the reservoir needing more frequent top-ups than historical baseline - gives a more complete picture, catching a mechanical seal that needs replacement before it progresses into a leak serious enough to affect pump performance or seal oil system pressure to the generator.

 

 

Since its inception, YOYIK has been adhering to the concept of technology-led, quality-first, and has brought together a large number of top engineers and technicians in the industry. With their rich experience in power station construction and maintenance, they provide customers with a full range of services from equipment selection to installation, commissioning, and maintenance. With its strong technical strength and perfect after-sales service system, the company has become a trusted partner of many large-scale power generation projects.

 

The following are various spare parts options that our company can provide for power facilities.

#DF-Generator AC sealing oil pump KF90NY/15F6-DF

Three-way valve J21Y-320P

Control system OPC/AST solenoid valve 4WE10y33/CG110N9K4/V

Fluorine rubber ring C8689052

Block valve SD61H-P54.550V

Servo valve CSDY3-63S

Accumulator bladder NXQ-L25/31.5-H

Wind pressure anti blocking sampler PFP-B-II

pressure hose SMS-12-1524mm-B

Radial bearings 3FK5F32KM-06-02

pressure hose SMS-15/N1/4-305mm-B

Stop valve J61H-300SPL

Mechanical shutdown electromagnet DFP-A1-DC110 

servo valve MooG-J761-003A

Electric stop valve J961Y-P55140V

ASCO valve EF8551G403 240DC

pressure relief valve YSF12-35/130-TH

Diaphragm valve YX-DN25

valve seat G131123

Needle valve SHV4.0

servo valve 0508.2247T0102.AW019

Control device for gas-liquid two-phase flow DH-KX DN200 PN4.0

pressure relief valve YSF12-85/130-KJ

Bladder & gas valve NXQ-AB-100/31.5 -L- Y

AST solenoid valve 0508.615T0301AW025 220VDC

ACCUMULATOR BOTTLE NXO2-F40/31.5-H

Stop valve J561Y-2500Lb

relief valve LOF 98H-1

solenoid valve 4WE10E3X/CG24NZ4B10

Solenoid valve body SV13-12V-O-0-00 HQ1615Z

Solenoid valve JZPK-003A

Automatic Air Release Valve A.R.I DG-10

Solenoid valve 0508.1095T0804.AW002

Instrument valve M221W-100P

oil seals 32 x 37 x 2.5 mm Thk

Motor rear end cover Y200L-4

globe valve 80FWJ1.6P

Generator AC sealing oil pump KF90NY/15F6

 

Valve G761-3039B

Screw pump coupling plum blossom gasket 190621

Fluoro Rubber O-Ring OR0030029

pipe joint QD9111-77

The electromagnetic valve 4WE10D-20/AG220N74

sealing ring OR-304-V

Stop valve J61Y-P5440V

PACKING VALVE SPINDLE 442-152739-8-A36

servo valve U270/5Z04

Gearbox M02225 1.5KW

oil pipe 16G2AT-HMPDN25-DK025-1400

Block valve SD61H-P54.5170V

Regulating valve R73G-4GK-RMN

Sealing ring XM-12-1.5-J7

Energy storage device NXQ-A-25/20-L-R/Y

sealing ring HB4-56J8-94

Stop valve J61Y-420I

BALL BEARING SINGLE ROW RADIAL DEEP GROOVE NO.6206

Solenoid valve 4WE6Y-L6X/EG110NZ4-V

O-ring Y7-6

gate Z960Y-250

Back pressure valve ZA-GN31

sealing ring HY-SO-0133-V

oil pump PVH98QIC-RSM-1S-10-C25-31

 Stop check valve K25JC-1.6P DN25

Impeller TFVP 250D-OEK4

servo valve 072-1203

RUBBER LINER SET NXQ-F40/315

HYDRAULIC PUMP PD060PC02SRS5AAM0E1200000

Pressure measuring hose SMS20/M1/4-2000A

pressure relief valve YSF9-70/80-KJTA

Pressure Relief Valve YSF9-70/130KKJ

Disc Sealing Ring D943H-6C

oil pump 2CY18-3.6

servo valve SM4-40-40-151-80/40-10-H919H

Sequence Cartridge valve LC16DB20D-6X

Generator AC sealing oil pump KF90NY/15F6

 

DFYLMY-2026-7-10-A