Tolteq Snubber: Testing and Comparison

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1 SUBJECT: PRODUCT: TOLTEQ SNUBBER: OVERALL PERFORMANCE IN COMPARISON TO COMPETING SNUBBERS TOLTEQ SNUBBER DATE: AUGUST 28, 2014 SCOPE The purpose of this test is to document the snubbing effectiveness of the new Tolteq snubber versus several competing brands, including the Tolteq Legacy-style snubber, under varying environmental conditions. There were two separate test setups used during the testing, however, once a module broke, no further tests were performed on that sample. The test sequence and time were noted for all tests. All testing was performed by Tolteq employees using Tolteq testing equipment. SUMMARY All devices were set-up and tested on the same vibration table under the same conditions. The snubbers were mounted with a Legacy-style 4-bolt pattern using stainless steel screws with Loctite, and torqued to spec. The Tested Samples The following tables lists the two Tolteq snubbers one a traditional Legacy-style and the other a more modern screw-less design and four leading industry designs, assigned letters A-D. Sample# Description 1 Competitor A 2 Competitor B 3 Tolteq Snubber 4 Competitor C 5 Competitor D 6 Tolteq Legacy Cedar Park, Texas Page 1

2 Results Of the six tested samples, half failed after the first test, Setup #1. Admittedly, this first test subjected the samples to severe prolonged vibration via a standard vibration table, as explained in the next section, Test Setups. The three remaining snubbers were subjected to the remaining two tests; however, as the Conclusion shows, two of the samples final states can hardly be described as functional. The Tolteq snubber survived the vibration testing of up to 45g s RMS. There were no signs of major wear to the unit: none of the fasteners were in danger of coming loose, and none of the elastomer material was destroyed. The Tolteq Legacy snubber failed in the first sequence of vibration testing. Due to this failure, no usable data was gathered. Competitors A s snubber survived vibration testing of up to 45g s RMS. There were no visible signs of wear to the unit after the test. All four of the fasteners that attach the unit to the bulkhead came loose. Also, the unit amplified shock and vibration events during ambient testing. Competitor B s snubber survived vibration testing of up to 45g s RMS. There were very visible signs of wear to the outside of the unit and to the anti-rotation feature. All four of the fasteners that attach the snubber to the bulkhead came loose, but the elastomer was undamaged during the testing. Competitor C s snubber assembly failed in the first sequence of vibration testing. Due to this failure, no usable data was gathered. Competitor D s snubber assembly failed in the first sequence of vibration testing. Due to this failure, no usable data was gathered. Cedar Park, Texas Page 2

3 TEST SETUPS Shock and vibration testing was setup in three different ways to emulate a wide range of conditions, and therefore get more useful data in the end. Setup #1: Vibration Table All samples were hard mounted to the table with a simulated chassis equipped with an accelerometer to read the snubbing effectiveness, as shown in Figure 1, Figure 2 and Figure 3. Snubber Assembly Figure 1: Vibration table with snubber assembly on the right Cedar Park, Texas Page 3

4 Snubber Assembly Un-snubbed Accelerometer Snubbed Accelerometer Snubber Assembly Figure 2: Close up of Tolteq snubber assembly, Sample #3, attached to vibration table Snubber Assembly Un-snubbed Accelerometer Snubbed Accelerometer Snubber Assembly Figure 3: Testing assembly for competitor s snubbers The accelerometers used are 3-axis accelerometers, mounted to the simulated chassis and hard mounted to the input of the snubber. Cedar Park, Texas Page 4

5 Setup #2: Vibration in Vertical Barrel The second vibration setup was closer to a downhole situation, as shown in Figure 4. The snubber was attached to the vibration table via a custom fixture, a beryllium copper barrel and a bulkhead. This test was run at ambient temperature and heated to 110 C. Simulated Chassis Snubbed Accelerometer Snubber Un-snubbed Accelerometer Mounting Fixture Figure 4: Vertical vibration fixture, ambient temperature Cedar Park, Texas Page 5

6 Thermal Blanket Figure 5: Assembly wrapped in thermal blanket Cedar Park, Texas Page 6

7 Setup #3: Shock Drop Test The shock testing was conducted on an assembly designed and built by Tolteq specifically for this test, as shown in Figure 6. All of the test units were attached to two linear slides and dropped onto concrete to obtain a saw tooth pattern shock event. A simulated chassis was attached to the snubber and bulkhead assembly, then the whole assembly was put inside of a BeCu barrel. Snubbed Accelerometer Heating element placed here during heated testing Figure 6: Drop test assembly The accelerometers were placed in two locations. The first was placed at the base of the assembly to register the initial shock to the system; the second was placed on the simulated chassis to register the snubbing efficiency of the device under test. Cedar Park, Texas Page 7

8 TESTING The following table list the specifics for each of the three tests, including a description of the test setup, as covered in the previous section, Test Setups. The samples are described in more detail in the previous section, Summary. Test Test Sample to Test Sequence Test Description 1 Vibration Setup #1 2 Vibration Setup #1 3 Vibration Setup #1 4 Vibration Setup #2 5 Vibration Setup #2 1, 4 Snubber/chassis NOT in a BeCu barrel Horizontal orientation Ambient Temperature Frequency 10Hz-10 KHz random all axis 46 g s RMS for 100 hours 2, 5 Snubber/chassis NOT in a BeCu barrel Horizontal orientation Ambient Temperature Frequency 10Hz-10 KHz random all axis 46 g s RMS for 100 hours 3, 6 Snubber/chassis NOT in a BeCu barrel Horizontal orientation Ambient Temperature Frequency 10Hz-10 KHz random all axis 46 g s RMS for 100 hours 1 Snubber/chassis in a BeCu barrel Vertical Orientation Ambient Temperature Frequency 10 Hz-10 KHz random all axis 46 g s RMS for 24 hours 2 Snubber/chassis in a BeCu barrel Vertical Orientation Ambient Temperature Frequency 10 Hz-10 KHz random all axis 46 g s RMS for 24 hours Cedar Park, Texas Page 8

9 Test Test Sample to Test Sequence Test Description 6 Vibration Setup #2 7 Vibration Setup #2 8 Vibration Setup #2 9 Vibration Setup #2 10 Shock Setup #3 11 Shock Setup #3 3 Snubber/chassis in a BeCu barrel Vertical Orientation Ambient Temperature Frequency 10 Hz-10 KHz random all axis 46 g s RMS for 24 hours 1 Snubber/chassis in a BeCu barrel Vertical Orientation Elevated Temp Frequency 10 Hz-10 KHz random all axis 46 g s RMS for 24 Hours 2 Snubber/chassis in a BeCu barrel Vertical Orientation Elevated Temp Frequency 10 Hz-10 KHz random all axis 46 g s RMS for 24 Hours 3 Snubber/chassis in a BeCu barrel Vertical Orientation Elevated Temp Frequency 10 Hz-10 KHz random all axis 46 g s RMS for 24 Hours 1-3 Snubber/chassis to be inside BeCu barrel Ambient Temperature 10 drops at 3-5 second intervals 1000 g s peak input 1-6 Snubber/chassis to be in a BeCu barrel. Drop is directly on snubber. Elevated Temperature 10 drops at 3-5 second intervals 1000 g s peak input Cedar Park, Texas Page 9

10 POST TEST ANALYSIS Tests 1-3: Vibration Setup #1 Because three of the tested snubbers (Competitor C, Competitor D, and Tolteq Legacy) failed as a result of this test, only the remaining three snubbers are shown in Figure 7. Figure 7: Snubbing Efficiency-horizontal, unheated Summary Figure 7 shows that the Tolteq Snubber performed slightly better than Competitor B. Competitor A s snubber actually increased the vibration in this test. Cedar Park, Texas Page 10

11 Tests 4-6: Vibration Setup #2 Figure 8: Snubbing Efficiency-vertical, unheated Summary Figure 8 shows the superiority of the Tolteq snubber in an unheated environment, with a 42.88% snubbing efficiency. Competitor A performed quite poorly by actually increasing the vibration in a vertical setup. Cedar Park, Texas Page 11

12 Tests 7-9: Vibration Setup #2 Figure 9: Snubbing Efficiency-vertical, heated Summary Figure 9 shows that the same snubber that performed so poorly at ambient temperature Competitor A actually outperformed the other two snubbers when heated. It was during this same testing, however, that Competitor A s snubber actually detached from the bulkhead (see the Conclusion). This event would have most certainly resulted in the tool s failure in a realworld application. Cedar Park, Texas Page 12

13 Test 10: Shock Setup #3 The following graph displays the shock, both snubbed and unsnubbed, placed on the remaining snubbers at ambient temperature. Figure 10: Test 10-Competitor A in the horizontal position, ambient temperature Summary In Figure 10, a single shock event is shown as experienced by Competitor A. The data shows that the snubbed end, as represented by the orange line, actually saw more shock than the unsnubbed end. Cedar Park, Texas Page 13

14 The following graph displays the shock, both snubbed and unsnubbed, placed on the remaining snubbers at ambient temperature. Figure 11: Test 10-Competitor B in the horizontal position, ambient temperature Summary In Figure 11, a single shock event is shown as experienced by Competitor B. The snubbed end, as represented by the orange line, performed well and saw 60% less shock than the unsnubbed end. Cedar Park, Texas Page 14

15 The following graph displays the shock, both snubbed and unsnubbed, placed on the remaining snubbers at ambient temperature. Figure 12: Test 10-Tolteq Snubber in the horizontal position, ambient temperature Summary In Figure 12, the Tolteq snubber performed well, with a 47.1% snubbing effect, as represented by the orange line. Cedar Park, Texas Page 15

16 Test 11: Shock Setup #3 Figure 13: Test 11-Competitor A, heated Summary In Figure 13, Competitor A s snubber performance, as represented by the orange line, is only slightly improved (12%) over its unsnubbed performance. Cedar Park, Texas Page 16

17 Figure 14: Test 11-Competitor B, heated Summary In Figure 14, Competitor B s snubber performance, as represented by the orange line, shows a 59% improvement over its unsnubbed performance. Cedar Park, Texas Page 17

18 Figure 15: Test 11-Tolteq Snubber, heated Summary In Figure 15, the Tolteq snubber showed a 61% improvement over its unsnubbed performance. Cedar Park, Texas Page 18

19 CONCLUSION Competitor A: Test Unit A s snubber survived all of the testing with no damage to the unit itself; however, all of the ambient temperature testing showed that its elastomer was extremely rigid, and in fact was amplifying shock and vibration events. During heated testing, the elastomer became softer and proved to dampen vibration very efficiently. During the heated vertical vibration testing, the four mounting screws holding the snubber and chassis assembly to the bulkhead backed all the way out, resulting in the assembly becoming loose and spinning freely inside the BeCu barrel. If the test had included a wired MWD tool, the wires would have completely broken and the tool would have malfunctioned. Competitor B: Test Unit B s snubber worked well throughout all of the testing. It was consistently either the top performer or very close to the top. During the heated vibration testing, the four mounting screws holding the snubber and chassis assembly to the bulkhead backed all the way out. The snubber and chassis assembly were then allowed to spin inside of the BeCu barrel. If the test had included a wired MWD tool, the wires would have broken and the tool would have malfunctioned. Cedar Park, Texas Page 19

20 After the heated vibration test, some very visible wear to the outer chassis of the Competitor B snubber was apparent, as shown in Figure 16. It appears that the anti-rotation feature in the assembly hammered the chassis during the test, resulting in a cracked housing. Crack in the Housing Figure 16: Competitor B showing a visible crack in the housing Cedar Park, Texas Page 20

21 The anti-rotation feature also caused the shaft to contact the snubber body, resulting in wear to both the body and the shaft, as shown in Figure 17 and Figure 18. Wear on the Mount Snubber Body Shaft Figure 17: Competitor B snubber shaft shown contacting body Damage to the Shaft Figure 18: Competitor B snubber shaft removed from body to show visible wear Cedar Park, Texas Page 21

22 Damage to the Body Figure 19: Competitor B snubber body opened to show wear caused by rotating shaft Damage to the Body Figure 20: Competitor B snubber body opened to show wear caused by rotating shaft Cedar Park, Texas Page 22

23 Tolteq Snubber: The Tolteq snubber performed exceptionally well throughout the testing. There were also no signs of any major wear on the assembly, and because the mounting screws have been eliminated from the assembly, it stayed intact throughout the testing. The remaining two competitors, on the other hand, separated at a now obvious weak point the mounting screws. Figure 21: Tolteq snubber Cedar Park, Texas Page 23

24 Competitor C: Competitor C s assembly failed during the first sequence of vibration testing. The shaft sheared off its mounting base, resulting in complete failure, as shown in Figure 22 and Figure 23. Based on our observations, this section is a weak spot for all modules made out of aluminum. Crack in the Shaft Figure 22: Competitor C snubber with crack in the shaft Broken Shaft Mount sheared from Shaft Figure 23: Competitor C in final broken state Cedar Park, Texas Page 24

25 Competitor D: Competitor D s snubber assembly failed in the first sequence of vibration testing. The mounting base sheared off the body, resulting in complete failure, as shown in Figure 24. Based on our observations, this section is a weak spot for all modules made out of aluminum. Snubber Body Snubber Shaft Mount sheared from Shaft Figure 24: Competitor D Snubber with the mount (bottom) broken off the body (top) Cedar Park, Texas Page 25

26 Tolteq Legacy Snubber: The Tolteq Legacy Snubber assembly failed the first sequence of vibration testing. The assembly failed when the shaft sheared off the mounting base, a weak spot for several other tested samples. The elastomer also experienced a catastrophic failure during testing. Snubber Body Figure 25: Tolteq Legacy Snubber body, separated from shaft Figure 26: Tolteq Legacy Snubber with mounting base separated from shaft (foreground). The elastomer inserts are shown in the background. Cedar Park, Texas Page 26

27 The Clear Winner As the results clearly show, the Tolteq snubber survived all of the testing while providing an exceptional level of shock and vibration snubbing. Although one other competitor performed slightly better in one test, it eventually detached and rotated freely, resulting in what would have become a tool failure in the real-world. As a result of this extensive testing, Tolteq s snubber has also undergone further refinements to the silicone based elastomer so that the module can perform better under heated vibration. Figure 27: Tolteq snubber, fully assembled Cedar Park, Texas Page 27