SCHAEFFER MFG S S HYDRAULIC FLUIDS WITH VARNISHIELD Lawrence G. Ludwig, Jr., CLS,OMA,CMFS

Transcription

1 SCHAEFFER MFG S S HYDRAULIC FLUIDS WITH VARNISHIELD Lawrence G. Ludwig, Jr., CLS,OMA,CMFS

2 Topics Functions of a hydraulic fluid Trends Equipment Fluid Performance Specifications VarniShield technology

3 Major Components Pump provides force to cause fluid flow Valves provides fluid direction control and maintains fluid pressure Reservoir stores the fluid Actuator converts hydraulic energy into mechanical energy - Linear/cylinder - Rotary/hydraulic motor Hydraulic fluid provides media for power transmission and lubrication

4 Hydraulic End-Uses/Markets Served Stationary Conveyors Food production Forming Injection molding Manufacturing Metal fabrication Packaging Paper Power generation Hydroelectric Gas/steam/combined cycle turbines Wind energy Printing Textiles Mobile Elevators Farm machinery Heavy construction Hoist/Crane Logging Mining Water transportation

5 Functions of a Hydraulic Fluid Transmit power and maintain pressure - Bulk modulus and viscosity Lubricate and protect. - Proper viscosity Provide sealing between moving parts Eliminate heat generated in service Accept and minimize the effects of contamination

6 Hydraulic Equipment Trends Systems are becoming smaller Pumps are getting bigger Operating pressures are increasing Up to 5000 psi, moving to 6500 psi Higher fluid temperatures Transient temperatures of 266 F (130 C) Drain intervals are increasing Increased focus on cleanliness/filterability Noise Legislation Encapsulation further reduces fluid cooling Less Oil + More Work = Increased Fluid Stress

7 Smaller Systems Smaller systems have a high tank turnover rate Reduced fluid volumes relative to pump flow rate Fluid is in constant movement Time available for air release is reduced Less residence time At higher pressures air bubbles are more soluble Cavitation damage can be catastrophic Surface damage due to formation of micropits Pump vibration Can also promote lubricant degradation Less time for the fluid to cool Oxidation and thermal degradation

8 Effects of Higher Pressures and Temperatures Lower pump volumetric efficiency Slower response time Reduced hydraulic power Fluid overheating Faster depletion of anti-oxidant and anti-wear additives Reduced fluid life. Higher oxidation rate Rate doubles for every 18 F F rise Fluid darkening, varnish deposits, valve sticking, filter plugging, bad odor Reduced equipment life Higher pump wear Shorter hose life Hardening at high temperature

9 Extended Drain Intervals Mobile Equipment Oil Drain Interval, hrs Equipment Manufacturer Previous Interval Today s Interval Komatsu 2,000 5,000 Hitachi 2,500 4,000 Caterpillar 2,000 4,000 Sumitomo 2,000 5,000 Volvo 2,000 4,000 JCB 1,000 3,000 10,000 hour specifications under development Requires all-year, multigrade fluid Fill to overhaul is the goal

10 What do all these equipment and operating trends mean to the hydraulic fluid? Fluid life can be diminished at a greater rate in providing protection in these harsher systems With less oil in the system, and expectations for longer lifetimes, a greater performance reserve is essential Hydraulic fluid quality and careful formulating are more critical than ever before

11 Fluid Performance- General Proper Viscosity Requirements Viscosity is the most important criteria. Viscosity directly influences the efficiency of the power transmission Wear Protection Oxidation and Thermal Stability Corrosion Protection Good Foam Resistant Characteristics Resistant to Air Entrainment Non-Compressible Good Demulsibility

12 Importance of Viscosity To high of a viscosity at start-up results in inadequate oil flow: Air entrainment Cavitation Noisy operations Sluggish response Energy loss Pump breakage in extreme cases

13 Importance of Viscosity To low of a viscosity once operating temperature is reached and the system is operating under load: High wear Excessive pump leakage Loss of system efficiency Excessive seal leakage Overheating Further reduction in viscosity Oxidation and thermal breakdown

14 OEM Viscosity Requirements

15 Hydraulic Fluid Performance Trends Filterability Alternative Base Stocks Wet Improved Fluid Finer Filtration Cleanliness Pore Size (Servo Systems) HWBF PAO, Syn Ester VHVI Fluids Natural Esters Multi-functional Hydraulic and Gear Hydraulic and Metalworking Hydraulic and Slideway

16 Hydraulic Fluid Environmental Trends Longer Useful Life Governing Factors Less Fluid in Larger Systems Extended Oxidation Resistance Water Pollution Classification Biodegradability Performance Additive Packages Zinc Free Zinc Ashless

17 Trends in Hydraulics Fluids Wear Protection When Wet Contamination with Water Often Happens Water Can Influence the Performance of the Fluid - Corrosion - Hydrolysis - Oxidation New Pump Tests Have Been Introduced with 1% Water - Denison T6C - Denison T6H20C

18 Trends in Hydraulics Fluids Air Release Due to smaller hydraulic systems, base oil air release properties have become important Systems become less precise when air contaminates the oil At moderate pressures, e.g psi, pumps cavitate The air release of the base oil impacted by refining process Some types of antifoam can negatively impact air release

19 Trends in Hydraulics Fluids Shear Stability Longer life fluids in mobile hydraulics require a wider operating temperature range Viscosity modifiers and pour point depressants will be required Hydraulic fluid shearing Result: Loss of viscosity, cavitation and pump damage

20 What s s in a Typical Hydraulic Fluid and Why Additive Package Base Oil + = Hydraulic Fluid 80 98% 2 20%

21 Base Fluid Types Used Petroleum Base - Group I Paraffinic Solvent Refined - Group II Paraffinic (Hydrocracked) Synthetic Base - Polyalphaolefin - Diester - Polyol Ester - Phosphate Esters - Polyglycols

22 Base Fluid Types Used Water- Based - Water Glycol - Emulsion Type - Oil-in in-water - Water-in in-oil - Synthetic Solutions Vegetable Oil Base

23 Components of Hydraulic Fluid Additive Package Additive Package Antioxidant Antiwear agent Demulsifier Detergent Dispersant Foam inhibitor Pour point depressant Metal deactivator Rust inhibitor VI Improver

24 Specifications - Denison Industrial Lubricants Hydraulic Trends Denison HF-0 - New Approval List Issued - Products over 10 years old need reconfirming - Products over 15 years old need reapproval To Obtain HF-0 - Hybrid Denison Pump (Jan 2004) Hybrid Pump T6H20C Piston and vane 600-hour test Inlet temperature = 248 F/120 F/120 C for dry test Inlet temperature = 176 F/80 F/80 C for wet test (1% water)

25 Specifications - Denison Trends in Hydraulics OEMs Denison Upgrading HF-0 Approval Vane Pumps Higher Pressures - up to 4,600 psi T6H20C

26 Hydraulics Some Key Specifications Eaton (Vickers) M-2950-S.. Mobile 35VQ25 vane pump I-286-S.. Industrial V-104C V vane pump In lieu of the V-104C V vane pump no longer being available, Eaton will accept 35VQ25 test results for the industrial specification

27 Market Data Cincinnati Machine Trends in Hydraulics OEMs Cincinnati Machine Approval Period Reduced from Five to Three Years - P-68: ISO VG 32 - P-70: ISO VG 46 - P-69: ISO VG 68

28 Hydraulics Some Key Specifications DIN Part 1 use circulating and R&O fluids Part 2 uses anti-wear; FZG, V-104C V + bench tests Part 3 is the multigrade version SAE HX-1 - Asian mobile equipment utilizes the Komatsu HPV35+35 piston pump JCMAS HK JCMAS HKB (biodegradable) Caterpillar HYDO (minimum 900 ppm Zinc)

29 Hydraulics Some key specifications ISO Classifications HH - Non inhibited oils HL - R & O oils HM - Anti-wear oils HV - Anti-wear multi-grade oils HS - Synthetic Fluids non fire resistant HFAE - Oil in water emulsions >80% water (fire resistant) HFAS - Chemical solutions in water >80% water (fire resistant) HFB - Water in oil (invert emulsions) 95/5 (fire resistant) HFC - Water Glycol (fire resistant) HFDR - Phosphate ester (fire resistant) HFDS - Chlorinated Hydrocarbon base (fire resistant) HDFT - Blends of HFDR and HFDS (fire resistant) HFDU - Synthetic fluid of other types (fire resistant)

30 Schaeffer s s VarniShield Technology Differentiation for Hydraulic Systems

31 Fluid Power Trends: It s s a tough world for hydraulic fluids Hydraulic systems are getting smaller Reservoir shapes are often not optimum Flow rates are high relative to oil volumes Oil residence times can be very short Hydraulic systems are designed with higher power densities Oil temperatures are higher > 266 F F transients are seen Oil pressures have increased OEMs agree these trends are leading to more frequent problems in high performance hydraulic systems

32 Consequences of this tougher world Foaming & cavitation through low residence times Shorter fluid life due to increased oxidation Poor hydraulic valve response due to sludge and varnish build up Increased need to replace blocked filters More wear on valves & pumps Varnish Oil Aging Filter Blockage

33 Comparing Today s s Hydraulic Fluids OEMs agree that as operating conditions become more severe varnish formation increases When sludge & varnish deposits are present sub optimal performance occurs An increase in varnish & sludge problems has occurred in the field Standard (duration) pump tests do not show the increased stress placed on many fluids today

34 What is Varnish? The polymerized oil oxidation products and decomposition byproducts derived by thermal breakdown. As the oil ages more varnish is formed. Can also be formed by Static discharge across high flow filters Cracks the oil generating auto-oxidation oxidation Microdieseling (implosion of entrained air bubbles) Localized temperatures of 1,800 F F can be reached Varnish is polar Ends up as a tenacious hard lacquer Attracted to metal surfaces Starts as a sticky soft residue Attracts wear debris

35 Extended Duration Pump Testing Extended 35VQ-25 vane pump testing is able to demonstrate this effect with various zinc-containing containing fluids After 500 hours a tenacious varnish deposit starts to form in the reservoirs and on pump parts when testing traditional hydraulic oils 1000 hours at full pressure & temperature shows a fluid s potential for varnish formation. Test conditions : Temperature = 203 F/ F/95 C Pressure = 3,000 psi/207 Bar Speed = 2,400 rpm Oil volume = 51.6 gals/197 litres

36 Why is Varnish so Bad for a Hydraulic System? Oil that is oxidized does not lubricate. Higher Friction Can cause hydraulic valves to stick - especially proportional and servo types Shortens the lives of components (valves, filters, pumps, bearings, seals etc) Oil flow is hindered and cooling capacity is often lost Potential system failures lead to equipment downtime and loss of operational income Bottom line hydraulic system performance suffers.

37 Varnish is Bad For Pumps, Too Vane pumps Increased noise Decreased volumetric and mechanical efficiency Increased energy consumption Side plate scuffing Stuck vanes in rotor slot Rotary seal damage Potential bearing failure Piston pumps Increased piston land friction against the wear plate Leakage and possible seizure Sticking valves Unscheduled stoppages during operation Filter blockage

38 What are End Users Experiencing? Increased focus on contamination control to maximize hydraulic performance Stringent filtration is becoming more common < 3 micron often seen End users are reporting impaired valve function due to varnish More frequent filter blockage, higher friction and sticky residues attracting wear-promoting solid particles Electrostatic filters used for sludge and varnish removal are expensive

39 Schaeffer Mfg Has the Solution VarniShield Traditional fluid technology 6 weeks continuous use 203 F/95 C 3000 psi/207 Bar Eaton Vickers 35VQ25

40 Varnish Eliminated Extended Pump Testing VarniShield Technology 6 weeks continuous use 203 F/95 C;3,000 psi/207 Bar Eaton Vickers 35VQ25

41 VarniShield Schaeffer Mfg s s New Technology #112, #112A, #254, #275SW & #275S Performance Profile: Meets and Exceeds Denison Hybrid Pump HF-0 Easily surpasses DIN Part 2 Eaton Vickers Vane Pump extended performance Exceeds Cincinnati Machine Thermal Stability Requirements. (25 mg sludge maximum) Advantages over current technologies: A clean, no varnish, deposit-free hydraulic system Longer oxidation life and reserves of performance (>3500 hrs D943) Excellent wear characteristics (FZG 12th Stage) Exceptional thermal stability (1.8 mg sludge in CM test)

42 VarniShield Pump Wear Protection Parker Denison T6H20C Hybrid Pump Performance Total weight loss End of dry phase End of wet phase Vanes weight loss 5.1 mg 5.8 mg Cam ring weight loss 18 mg 161 mg Pistons total of all mg 274 mg Increase in wet phase differential pressure was exceptionally good (2.9 psi/200 mbar) Hybrid Pump testing meets all criteria for Parker Hannifin s s (Denison) HF-0 0 specification

43 VarniShield Pump Wear Protection Eaton-Vickers 35VQ/25 Vane Pump Test 3000 psi, 2400 rpm, 203 F, 150 hours Total Ring & Vane Wt. Loss, mg Schaeffer s Hydraulic Fluids Eaton - Vickers M-2950-S Eaton Vickers I-286-S max 90 max Meets and Exceeds Eaton-Vickers Specifications

44 Additional Performance Benefits Excellent demulsibility so water separates quickly (15 minutes) in ASTM D-1401 D Demulsibility Test Excellent Hydrolytic Stability Excellent filterability even in the presence of water Very good anti-foam and air release properties High level of rust and corrosion protection to extend component life Energy savings

45 Water Contamination Water can enter the fluid through: Access plates in the reservoir Condensation Wash down Heat exchanger leaks Small amounts of water can be tolerated Too much water in a system can cause: Collection of contaminants Additive depletion Sticky valves and servos Formation of acids that can corrode yellow metals Rusting and corrosion Accelerated wear Plugged filters

46 Excellent Demulsibilty Characteristics Today s s hydraulic systems are smaller and designed to do more work Fluid spends very little time in the reservoir consequently, hydraulic fluids must have a high degree of demulsibility Demulsibility is the ability of the fluid to separate from water Schaeffer Mfg s s hydraulic fluids with VarniShield have a higher degree of demulsibility as demonstrated by the ASTM D-1401 D Test Method For Water Separability

47 Hydrolytic Stability Measure of the reactivity of the fluid s s anti-wear additive system with water Under heat and pressure the anti-wear additives can react with water to form acidic components. Corrosion of yellow metals Formation of sludge Loss of anti-wear protection It is important that the fluid have good hydrolytic stability to protect all yellow metal components even when small amounts of water enter the system

48 Excellent Hydrolytic Stability Schaeffer Mfg s s hydraulic fluids with VarniShield have a higher degree of hydrolytic stability as demonstrated by the ASTM D-2619 D Hydrolytic Stability Test Method ASTM D-2619D Schaeffer s Hydraulic Fluids Copper wt. Loss, mg/cm2 Acidity of Water Layer, mg KOH/g Denison HF-O Maximum Limits

49 Filterability Water contamination can cause plugging of filters Blocked filters can be a major maintenance issue in the field With the increased use of finer filtration (<3 microns) in order to keep the fluid clean this has become more of an issue The Denison HF-O O specification address this issue

50 Excellent Filterability in the Presence of Water Denison Filterability Test TP A Performance Schaeffer s Hydraulic Fluids Denison HF-O Maximum Limits Filtration time without water, seconds Filtration time with 2% water, seconds 163 2X filtration time without water

51 Foaming and Air Release Air can enter through the reservoir or through air leaks within the hydraulic system Air can lead to foaming and additional air entrainment Use of smaller reservoirs aggravate the problem. Not enough setting time Foaming can be aggravated by: High operating pressures High operating temperatures High flow rates and pump speeds Low oil levels Contamination

52 Foaming and Air Release Foaming can cause: Accelerated oxidation of the fluid Higher operating temperatures Pump cavitation Decreased lubricity Shortened component life Air can also become entrained in the fluid Bubbles suspended in the fluid (<1mm in diameter) Under low pressure the fluid absorbs 10% air by volume. Entrained air can result in: Spongy controls Cavitation Noise Pressure spikes Loss of horsepower Temperature increases Fluid oxidation

53 Foaming and Air Release Foaming can be controlled by the use of antifoam additives Some types of anti-foam or use of too much can impair the fluids air release properties. Retard the release of dissolved air A fluid s s air release properties are dependent upon the type of base stocks used.

54 Foaming and Air Release Schaeffer s Hydraulic Fluids DIN Part 2 Max limits Sequence I Sequence II Sequence III 0/0 150/0 0/0 75/0 0/0 150/0 Schaeffer s Hydraulic Fluids Denison HF-0 0 Maximum Limits Air release time, minutes

55 Plastic Injector Molding VarniShield Cost Savings Example

56 Plastic Injection Molder Example 3-44 servo valves per machine 10% of valves replaced annually due to sticking issues Typical cost to replace servo valve $2000 to remanufacture $3000 for new Average time to replace servo valve is one hour Labor rate is $50/hour

57 Costs Large Injection molding shop may replace 60 valves per year 60 valves x $3000/new valve = $180,000/year or 60 valves x $2,000/remanufactured valve = $120,000/year Typical time to replace valves 60 valves x 1 hour/valve = 60 hours 60 hours x $50/hour = $3,000 Total cost* $123,000 to $183,000 *Does not include production downtime or labor and cost for replacement of pumps

58 Total Cost Total cost per year due to varnish not including production loss is $123,000 to $183,000 per year

59 Summary The use of Schaeffer Mfg s s hydraulic fluids with VarniShield heralds a new era for cleaner hydraulic systems Varnish and sludge problems are minimized or eliminated A high resistance to oxidation means longer oil life System component life can be extended Equipment downtime and costs due to maintenance issues can be significantly reduced For heavily varnished systems it is suggested that a purge with Schaeffer s s #287 Food Grade Flush be conducted