SAP Parts-Mechanical Face Seal Testing Capabilities In-House Seal Testing & Validation Program SAP PARTS PVT.LTD.INDIA July 25, 2017 Authored by: K.Jayant Address: 85,B.U.Bhandari Indl.Estate, Snaswadi, Pune 412208,INDIA www.sapparts.com
SAP Parts-Mechanical Face Seal Testing Capabilities 25/07/2017 SAP Parts-Mechanical Face Seal Testing Capabilities In-House Seal Testing & Validation Program SAP Parts Pvt. Ltd. is a leading manufacturer of Mechanical Face Seals globally serving innovative sealing solutions to OEMs, with technologically advanced and of superior quality, performance and suitability in highly challenging application environments. Based on the application needs of the Sealing Solutions provided, in order to validate the product design SAP Parts has established a state-of the- art Seal testing Centre, where a number of Test Programs are designed and run to estimate the credentials of the performance of seals made by SAP Parts. This facility is capable to manufacture mechanical face seals for challenging applications as well as to test various performance parameters of Seals with respect to - Endurance testing: - Load, Torque, Wear, Speed, Leakage, Hardness etc. Material Specifications testing: - Chemical & Physical Properties, Microstructure, Morphology of Sealing Surfaces & SEM analysis as well as For O Rings -Aging of elastomers, Oil Compatibility, Compression Test, Specific gravity Test etc. Geometrical attributes testing: - Flatness, Surface Finish, Contact Geometry, Sealing profile. Computational Analysis: - FEA of elastomers, Contact Pressure, Load, Deflection etc. Following pages explain in detail about the test Facilities available, Plan of testing, Sample Test Report, Comparable analytical test report against Competitor, and a brief features of various Customer Specific application sealing solutions developed by SAP Parts. 1
Endurance Test Rig Set Up The Seal Technology Centre at SAP Parts, is equipped with a number of different Test Rigs for validation of Seals Performance based on the Size & Environmental requirements of applications where the seals are employed. Following are the details of such Test Rigs available for performance and endurance tests. SEAL ENDURANCE & LEAKAGE TEST RIG SPECIFICATIONS DIFFERENTIAL PRESSURE SEAL ENDURANCE & LEAKAGE TEST RIG Type Test Sample Size Max. Speed Max Load Pressure Differential Pressure Test Capabilities Mud Packing Test: Heat Generation Test Pressure Velocity Test SPECIFICATIONS SCADA Controlled Seal<300 mm Outside Dia. 5 M/s 250KgF External NA Mud Submerged Wear and Leakage with Contamination Test. Time v/s Pressure v/s Surface Speed in Lubrication to study amount of Heat Generated. Pressure v/s Velocity(Linear Speed) Wear, Galling and Spilling Test SEAL ENDURANCE & LEAKAGE TEST RIG Type Test Sample Size Max. Speed Max Load Pressure Differential Pressure Test Capabilities Mud Packing Test: Heat Generation Test Pressure Velocity Test SPECIFICATIONS Type Test Sample Size Max. Speed Max Load Pressure Differential Pressure Test Capabilities Mud Packing Test: Heat Generation Test Pressure Velocity Test SCADA Controlled Seal<300 mm Outside Dia. 5 M/s 200 KgF External/Internal Diff. Pressure : 7 Bar Mud Submerged Wear and Leakage with Contamination Test. Time v/s Pressure v/s Surface Speed in Lubrication to study amount of Heat Generated. Pressure v/s Velocity(Linear Speed) Wear, Galling and Spilling Test SCADA Controlled Seal<1100 mm Outside Dia. 5 M/s 1000 KgF External NA Mud Submerged Wear and Leakage with Contamination Test. Time v/s Pressure v/s Surface Speed in Lubrication to study amount of Heat Generated. Pressure v/s Velocity(Linear Speed) Wear, Galling and Spilling Test Note: The recommendations in this specification are designed to provide the best advice available but should not be considered as a legally binding warranty. All rights in accordance with ISO 16016-2016 are reserved. All the images displayed are only for elaboration of the content, and not intended to breach the proprietary rights of the owners if any. 2
SAP Parts-Mechanical Face Seal Testing Capabilities 25/07/2017 Product Testing Set-Up Apart from the seal performance test, the Seal Technology Centre is equipped with several other high end testing facilities which endorse the quality parameters and attributes of the products developed. Specific Gravity Tester Durometer Compression-set Tester Hardness Tester Compound Microscope Degital Height Gauge Surface Finish Tester Degital Height Gauge Coordinate Measuring Syster ( FARO) Low Temp.Tester Optical Flatness Tester Stereo Microscope - Surface Scratch Testing 3
Seal Validation Plan Note: The recommendations in this specification are designed to provide the best advice available but should not be considered as a legally binding warranty. All rights in accordance with ISO 16016-2016 are reserved. All the images displayed are only for elaboration of the content, and not intended to breach the proprietary rights of the owners if any. 4
SAP Parts-Mechanical Face Seal Testing Capabilities 25/07/2017 Comparable Seal Testing Material Test Analysis 5
Comparable Seal Testing Endurance Test Analysis TEST SETUP : MECHANICAL FACE SEAL ENDURANCE TEST - SAMPLE REPORT Comparative Testing of Seal Samples - SAP Parts V/s Competitor Seals TEST RIG SYSTEM FOR MECHANICAL FACE SEAL - OIL LEAKAGE & LIFE ESTIMATION REPORT NO/SAP/SLTR/XXX DATE:-21/1/2017 PAGE No:-1 of 1 SAMPLE REF /DRG NO. CUSTOMER CODE : XXXX Sr.# Test Name Test Output Specifications Observations: SAP Parts Sample Observations: Competitor Sample 1 Seal Fitment Test Seal Fitment in Housing Seal Fitment by Install Tool Assembly Height variation ± 0.3mm Easy Fitment using Install Tool Within Tolerance Easy fitment by using tool Within Tolerance 2 O-Ring aging Test Compression Set of "O" Ring NBR60-Air aging 72Hrs @ 120 C Compression set < 30% 22% 35% 3 O-Ring Compatibility Test Change in Volume of O Ring NBR60-oil aging ASTM Oil #1 change in volume ±5% NBR60-oil aging ASTM Oil #3 change in volume +45% -3.50% 7.50% -5.0% 12.00% 4 Face Load Profile Test Estimate Load V/s Deflection Face Load Exerted @3mm Gap : 1 N-mm 1 N-mm 1.1N-mm 5 Oil Leakage Test Oil Leakage From System No Leakage @ 3m/s No Leakage Observed Leakage Observed - 58 Hrs. 6 High Temp. Oil Test Seal Performance at high temp. No Leakage @10 RPM @22Hrs < 70 C No Leakage Observed Leakage Observed - 22 Hrs. 7 Low Temp. Oil Test 8 Mud Box Test 9 10 Differential Pressure Test Spin (Ramp Up / Down) Test Conclusion: Seal Performance at Low Temp. Seal Performance under Mud Box Seal Performance under Differential Pressure. Seal Performance under variable RPM & Time. No Leakage@ Low temp @10 RPM @22Hrs @ - 25 C Oil Contamination NASH-1638 Sustain the Differential Pressure of 3 Bars @ 150 RPM Sustain during Ramp Up to 174 RPM @ 2.2m/s Ramp Down to 0 RPM every 15 Min.For 166 Hrs. No Leakage Observed Found Within Specification No Leakage Observed No Leakage Observed No Leakage Observed. Found Within Specification Leakage Observed - 1.5 Hrs. Leakage Observed - 7 Hrs. SAP Parts Seal Sample has qualified the oil leakage test for the standard test conditions,resulting No Oil Lekage, and break down. The product specifications post test observed to within acceptance criteria.seal Performance is validated. Competitor Seal Sample tested for the endurance exhibited premature failure and witnessed substantial Oil Leakage at intermidiate duration before completion of the respective test cycles, hence do not qualify the acceptance criteria. Seal performance is not Validated. Prepared By GLJ Engineer- Testing SAP/SLTR/03-2017 Reviewed By ASB QA Approved By PBK Head - R&D Note: The recommendations in this specification are designed to provide the best advice available but should not be considered as a legally binding warranty. All rights in accordance with ISO 16016-2016 are reserved. All the images displayed are only for elaboration of the content, and not intended to breach the proprietary rights of the owners if any. 6
SAP Parts-Mechanical Face Seal Testing Capabilities 25/07/2017 Customer Specific Solutions Developed -1 SECTOR - Agricultural technology/agricultural machinery PROBLEM - Frequent service demand of the PTO shaft seals on account of Leakage due to wear and thermal overloading. Service life of 1 season ( 6 Months) PROJECT - To provide a sustainable sealing solution suitable for the mud environment instead of existing normal cassette sealing. NEW PRODUCT. USAGE - Sealing the power transmission output shaft of agriculture tractors working in mud submerged conditions like paddy field. For global use in agricultural engineering technology combined with customer-specific external and internal media. REQUIREMENT- Defining an improved sealing system by a introducing a Service Free Product for PTO sealing and improving the wear or abrasion behavior and increasing the temperature resistance. SOLUTION - An unique design of mechanical face seal made which unitizes the seal in a housing filled with grease and sleeved on a bush which further fits on the shaft locks the seal housing hub cavity. While the shaft rotates half seal mounted on the sleeve slides against another fixed half face of mechanical seal, thus oil seals. External mud entry is permanently avoided by the collar of sleeve faced to environment. TESTING - The unitized mechanical seal is tested for the performance on the test bench were simulated by means of inadequate lubrication at points, and external impact from defined dirt using a mud box and seal tested for 1000 hours at accelerated test conditions and found no leakage or failures. RESULT - The outstanding sustainability for oil leakage at elevated speed even up to 1400 RPM of this unitized mechanical seal, is what brings particular added value. The resulting longer service life not only makes up for the increased price compared to normal cassette seals, but when combined with the increased temperature resistance, also provides the possibility of increasing the speed and therefore the operating speed of the machines. ADVANTAGE- On field tests No leaks after 1200 hours. 7
Customer Specific Solutions Developed -2 SECTOR - Agriculture Machinery/Equipment PROBLEM - Existing Metal Face Seal 100Cr6 + O-Ring NBR 60 combination observed failure of seals by Wear and Oil Leakage due to increased friction forces and frictional heat, at high speed conditions less than 5M/s. PROJECT - To provide a tested sealing system for Mid- Rollers of rubber track undercarriages for agricultural harvesting application at high speed conditions more than 5M/s USAGE - Rubber Track Rollers REQUIREMENTS- Increasingly fast-running undercarriage agriculture applications bring about higher circumferential speeds, temperatures and friction levels. The resulting wear pattern on the existing sealing rings needs to be significantly and sustainably improved. The proposed design was checked and optimized for Low torque capabilities, Pressure peaks that sometimes occur, as well as the application-specific parameters -speed, temperature, direction of rotation etc. Seals of superior leakage & speed performance combined with minimal friction at high speed conditions is developed and tested. APPROACH - Computational Modeling approach was adopted to correct the optimal seal profile which can exert minimum pre-loading on the seal faces. Close observation and FEA analysis of O-Rings in compressed condition yield the load values, the same is also verified on the test bench, by means of the pressure applied on load cell. To reduce the frictional heat, Nihard alloy cast iron having higher abrasion resistance was proposed, the sealing faces employed with WS2 coating which reduce co-efficient of static & dynamic friction substantially, and O-rings from NBR of High temperature capability introduced, Thus making seal to perform at higher surface speeds with reduced friction heating. Test bench runs and testing carried out in multiple steps on the whole seal at the Lab as well as customer's premises ultimately lead to an optimal geometry correction. RESULT - Employing improved LF (low friction) technology, on the metal faces seals made from Ni-hard cast alloy material, and introducing NBR with high temperature capabilities, it was possible to meet the customer's more demanding usage conditions. The optimal balance between contact pressure and leak-tightness was achieved with the close collaboration between technology and development over the course of 6 months. ADVANTAGE- Friction behavior improvement Temperature Stabilized to 70 C Note: The recommendations in this specification are designed to provide the best advice available but should not be considered as a legally binding warranty. All rights in accordance with ISO 16016-2016 are reserved. All the images displayed are only for elaboration of the content, and not intended to breach the proprietary rights of the owners if any. 8
SAP Parts-Mechanical Face Seal Testing Capabilities 25/07/2017 Customer Specific Solutions Developed -3 SECTOR - Rock Drilling/TBM PROBLEM - Existing metal face Seal was failing due to high pressure difference between external environment and internal hydraulic pressure of oil. PROJECT - To provide sustainable sealing solution for Tunnel Boring Machine cutter rollers working in very high differential pressure environments. USAGE - Cutter Roller of TBM REQUIREMENTS- Rock cutters employed in TBM are subject to enormous differential pressure created by virtue of rock slurry outside and Oil inside sealing system. Also the cutter speed in hard rock and soft rock situations is differential that exhibit spinoff of cutter roll. Existing seals from 100Cr6 Steel + NBR combination exhibit slip over of O-rings from seal housing cavity in excessive differential pressure conditions leads to premature failure of seal and cutter roller stalling. APPROACH - Product development for severe applications like rock cutting essentially demands most appropriate selection of material. Proposed mechanical face Seals from High chrome Moly alloy cast iron, which is designed to provide abrasion resistant properties with maximum hardness. It has been used in the hardened plus tempered condition. When heat-treated, it attains the highest hardness about Rockwell C 60. The O-Ring elastomer to withstand high differential pressure of rock slurry and hydraulic system oil, proposed Silicon60, exhibit most reliable results when put to test. RUNNING TEST - A special Differential Pressure Mud Box test bench, capable to withstand high differential Pressure up to 7 bars, is established to test this seal and external environment of rock slurry is simulated. The slurry can be pressurized by means of pump and inside hydraulic oil can be pressurized by hydraulic system. The seal intact in the mud box is run at regulated differential pressure cycles and various speeds to test the performance, especially leakage & break down, for 184 Hrs. RESULT - The test exhibit Seal withstanding to differential Pressure of 7 Bars without failure of O- Ring. 9