FSRUG Feedwater Systems Reliability Users Group Jan 2014

FSRUG Feedwater Systems Reliability Users Group (Jan 2014) San Antonio, TX Stuffing Box Design & Configurations Presenter: Art Washburn, P. E.

FSRUG

FSRUG What is going on at this House? No Driveway, No Sidewalk…

FSRUG City of Raleigh Public Utilities Water Booster Station Pumps 45 Million Gallons per Day

FSRUG Virginia Beach Pump Station (Lake House)

FSRUG Pump Station (Greek Architecture)

FSRUG Office Building? . . .

FSRUG Electrical Sub-Station

FSRUG DISCUSSION POINTS • Two Rules to Get You Home and Plant Priorities • Case 1: API Plan 11 – Packing Injection Flush… Exhibits Excessive Leakage During Operation and Standby (Horizontal Multi-Stage Pump in Auxiliary Service Water Service) • Case 2: API Plan 13 – Reverse Flush System… Exhibits No Reverse Flush (Static System), Excessive Packing Leakage, Excessive Packing Sleeve Wear and Severe Stuffing Box Bearing Damage (Vertical Pump in Screen Wash Service) • Case 3: API Plan 13 – Reverse Flush System… Exhibits Excessive Packing Leakage (Vertical Pump in Condensate Service) • Case 4: API Plan 13 – Reverse Flush System with Bypass Port (Water Service and Hydrocarbon Service) • Source References

FSRUG Two Rules:

FSRUG Two Rules: Rule #1 – Make Conservative Decisions

FSRUG Two Rules: Rule #1 – Make Conservative Decisions Rule #2 – Maintain Design Control

FSRUG Two Rules: Rule #1 – Make Conservative Decisions Rule #2 – Maintain Design Control Plant Priorities:

FSRUG Two Rules: Rule #1 – Make Conservative Decisions Rule #2 – Maintain Design Control Plant Priorities: 1. Nuclear Safety

FSRUG Two Rules: Rule #1 – Make Conservative Decisions Rule #2 – Maintain Design Control Plant Priorities: 1. Nuclear Safety 2. Legal Requirements

FSRUG Two Rules: Rule #1 – Make Conservative Decisions Rule #2 – Maintain Design Control Plant Priorities: 1. Nuclear Safety 2. Legal Requirements 3. Efficiency

FSRUG Case 1: API Plan 11 – Packing Injection Flush (Original) Conditions: Excessive Packing Leakage - In Service - In Standby

FSRUG Case 1: Horizontal Multi-Stage Pump Sectional Aux Service Water Pump Stg 1, 260 psi Psuction, 30 psi

FSRUG Case 1: In-Board Bearing Housing Assembly Conditions: Packing Leakage Sprays Directly on Bearing Housing Water Intrusion in Bearing Housing Displaces Approx. 50% of Oil

FSRUG Case 1: Stuffing Box Configuration (Original) Conditions: Lantern Ring Mis-Aligned Inner Packing Rings - What Can You Do For Me Today?

FSRUG Case 1: API Plan 11 – Injection Flush System (Original) Measured Stuffing Box Pressure Pstuff box, 260 psi Stg 1 – 260 psi Pstuff box, 260 psi Psuction, 30 psi

FSRUG Case 1: Stuffing Box Configuration (Updated)

FSRUG Case 1: API Plan 11 – Injection Flush System Pstuff box, 35 psi Stg 1 – 260 psi Pstuff box, 35 psi Psuction, 30 psi

FSRUG Case 1: Stuffing Box Configuration (Updated)

FSRUG Case 1: Stuffing Box Configuration (Updated) Results: 1. Packing Sleeve Diameter, 4. 000 Inches 2. Required Flush for Packing or Mechanical Seal in Water Service and Fluid Temperature Less Than 150 o. F (1 GPM per 1 Inch of Shaft Diameter): 5 GPM 3. Stuffing Box Pressure: Maintains Positive Pressure, Easier to Adjust Packing, Reduced Frequency of Packing Adjustments, Eliminate Risk of Packing Spray Impingement on Bearing Housing

FSRUG Case 1: Stuffing Box Configuration (Updated) Analysis Process: 1. Simplify Equation of State to 2 Pressure Drop Devices or Less 2. Iterate Pressure Drop Determination for Both Devices to Share the Total Pressure Until a Mass Balance is Achieved (in GPM) 3. Result: Highly Predictable System Behavior

FSRUG Water Intrusion – Traditional Oil Deflector vs. INPRO Deflector See EPRI NMAC Lube Notes, November 2004, Bearing Operation with an Oil-Water Mixture

FSRUG Case 2: API Plan 13 – Reverse Flush System (Original) Conditions: Screen Wash Pump Pdischarge, 85 PSI Lantern Ring, Grease Filled Packing exposed to pump discharge pressure Bearing, High Pressure Breakdown Device (Static, melts)

FSRUG Case 2: API Plan 13 – Reverse Flush System (Original) Conditions: Excessive Packing Wear

FSRUG Case 2: API Plan 13 – Reverse Flush System (Updated) Conditions: Screen Wash Pump Pdischarge, 85 PSI Replaced Bottom Packing with Spacer (Controlled Clearance) Lantern Ring, Leak Off Thru Tubing (Orifice) to Sump Bearing d. P, 82 PSI Tubing d. P, 3 PSI Packing, 3 PSI

FSRUG Case 2: API Plan 13 – Reverse Flush System (Updated) Analysis Seeks Mass Balance Thru the Bushing and Orifice: Bushing: Orifice:

FSRUG Case 3: API Plan 13 – Reverse Flush System (Original) Conditions: Condensate Pump Excessive Packing Leakage Pdischarge, 515 PSI Pabove bushing, 170 PSI

FSRUG Case 3: API Plan 13 – Reverse Flush System (Original) Conditions: Condensate Pump Bottom Lantern Ring Significantly Blocking Plan 13 Return to Suction Lantern Ring Annulus Area too Small – Region Under Packing Does Not Depressurize Packing Sleeve Wear Excessive

FSRUG Case 3: API Plan 13 – Reverse Flush System (Updated) Conditions: Condensate Pump Bottom Lantern Ring Resized to Assure Plan 13 Return is Not Blocked Lantern Ring Annulus Area Increased to Allow Depressurizing Region 360 Degrees Around Shaft

FSRUG Case 3: API Plan 13 – Reverse Flush System (Updated) Conditions: Condensate Pump Interstage Pressure Acting on Packing Rings is Low, Gland Water Injection Maintains Positive Pressure on Packing to Prevent Air In-Leakage Packing Leak-Off Easily Controlled and Sleeve Wear Low

FSRUG Case 4: API Plan 13 – Reverse Flush System with Bypass Port(s)

FSRUG Case 4: API Plan 13 – Reverse Flush System with Bypass Port(s) Conditions: Bypass Port(s) may Not be Required for Water Service Bypass Port(s) are Required for Hydrocarbon Service (Low Specific Gravity Product)

FSRUG SOURCE REFERENCES: • Centrifugal Pumps: Design & Application, Lobanoff and Ross (practical application) • Centrifugal and Axial Flow Pumps, Stepanoff (theory) • Centrifugal Pumps, Gülich • Vertical Turbine, Mixed Flow & Propeller Pumps, Dicmus • Centrifugal Pump Handbook, Sulzer • Pump Handbook, Karassik • Centrifugal Pump Clinic, Karassik • Centrifugal Pumps Selection & Operation, Karassik • Centrifugal Pumps, Karassik • In-Tandem 3. 0 for Windows, EG&G Sealol (John Crane) • ABZ Inc, Design Flow Solutions Software

FSRUG WHO IS THIS SYSTEM ENGINEER?

FSRUG TAYLOR SMITH – Comanche Peak

FSRUG THE (HAPPY) END QUESTIONS ?