Compliance with API Standard 670 the PRO Product Standard for Proximity Probes

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3 Connection Technology Center, Inc Rae Boulevard Victor, New York Toll Free: (800) Phone: (585) Fax: (585) Compliance with API Standard 670 the PRO Product Standard for Proximity Probes Background: The American Petroleum Institute (API) issued their first standard in Since then, some 500 standards for the oil, gas and power industry have been issued. API is an American National Standards Institute (ANSI) accredited standards development organization, and API Standard 670 was developed for Machinery Protection Systems. The current 4 th edition is available from the API for the cost of $ USD, and can be ordered in a pdf file format. The API Standard 670 has global acceptance through active involvement with the International Organization for Standardization (ISO) and other international bodies. Connection Technology Center, Inc. (CTC) is an ISO 9001:2008 certified manufacturer of Vibration Analysis Hardware. Started in 1995, CTC specialized in manufacturing cables and connectors for industrial vibration applications. The product line now offers accelerometers, piezo velocity sensors, junction boxes and mounting hardware providing a full range of products for measuring acceleration and velocity on industrial machinery. In 2007, CTC formed the Protection & Reliability Optimization Instruments (PRO) division with an initiative to manufacture proximity probes, extension cables, oscillator-demodulators (drivers), and mounting hardware for the non-contact measurement of shaft displacement in fluid film bearing applications. This initiative conforms with or exceeds API Standard 670, and provides industry with a means to quantify the shaft vibration and shaft location in a fluid film bearing to avoid catastrophic bearing failure. PRO proximity probe systems provide an output of 200 mv/mil (1 mil = inches) or 7.87 mv/µm when calibrated with 4140 steel in accordance with API Standard 670. Connection Technology Center, Inc. 1

4 Machinery Protection Systems: The machinery protection systems described in API Standard 670 were developed for fluid film bearing systems that consist of a shaft, bearing sleeve, and lubricant between the shaft and sleeve. There are no rolling elements in a fluid film bearing. The shaft is supported by a lubricant as it rotates inside the sleeve. This creates the need to have a sensor that can measure the shaft vibration and shaft location inside the sleeve using a non-contact means. Typically, two proximity probes are installed on or in the bearing housing 90 o apart at the radial locations as illustrated in Figure #1. Figure #1 Proximity Probe Mounting Diagram Alternatively, proximity probes can also be used to measure the axial shaft position (thrust), rotational speed, keyway phase reference, case expansion, and in a reciprocating machine, piston rod drop. Radial proximity probes are often referred to as X and Y when viewed from the driver to the driven machine component. In Figure #2, if viewed from the driver to the driven, the Y probe would be on the left and the X probe would be on the right. Connection Technology Center, Inc. 2

5 Proximity Probe Y 90 o X Proximity Probe Bearing Sleeve Shaft Lubricant Figure #2 X and Y Radial Proximity Probes Figure #2 also illustrates that the X and Y proximity probes are spaced 90 0 apart from each other, and that the inside of the bearing sleeve is counter bored to prevent interference on the side of the sensing tip. The direction of rotation never determines which probe is X and which probe is Y, but the two probes can be used to identify the direction of rotation. If the Y probe leads the X probe by a phase difference of 90 o, the shaft is rotating clockwise. If the X probe leads the Y probe by a phase difference of 90 o, the shaft is rotating counter clockwise. System Components: A proximity probe system is made of three specific components: 1. Probe 2. Extension Cable 3. Driver (oscillator-demodulator) Connection Technology Center, Inc. 3

6 1. Probe: Figure #3 Forward Mount Proximity Probe API Standard 670, section states that a proximity probe consists of a tip, a probe body, and integral coaxial cable, and a connector as specified in 5.1.3, and shall be chemically resistant as specified in 4.4. PRO proximity probes are manufactured with a resilient polyphenylene sulfide (PPS) tip, stainless steel body, Teflon jacketed cable and gold plated connectors to provide robust non-contact displacement sensors, capable of performing in harsh environments. API Standard 670, section states that unless otherwise specified, the standard probe shall have a tip diameter of 7.6 to 8.3 millimeters (0.300 to 0.327in), with a reverse mount, integral hex nut probe body approximately 25 millimeters (1in) in length and 3/8-24 UNF-2A threads. PRO proximity probes for forward and reverse mounting are constructed with a 3/8-24 threaded stainless steel body (case). The reverse mount probe body (case) is 33 millimeters (1.3 inches) in length with an integral 11 millimeter (7/16 inch) hex nut whose tip diameter is 8 millimeters (0.315 inches). The forward mount probe, as shown in Figure #3, is available in multiple case lengths (1.0 to 9.5 inches in 0.5 inch increments), multiple unthreaded lengths (0.0 to 8.0 inches in 1.0 inch increments), and multiple overall lengths ( note that the overall length with and without an extension cable must equal 5 meters or 9 meters). Forward mount probes incorporate two 11 millimeter (7/16 inch) hex nuts for mounting purposes. API Standard 670, section states when specified, the standard options may consist of one or more of the following forward mount probe configurations. a) A tip diameter of 7.6 to 8.3 millimeters (0.300 to inches) and 3/8-24-UNF-2A English threads. PRO proximity probes have an 8 millimeter (0.315 inches) tip diameter. Connection Technology Center, Inc. 4

7 b) A tip diameter of 4.8 to 5.3 millimeters (0.190 to 0.208in) and 1/4-28- UNF-2A English threads. c) A tip diameter of 7.6 to 8.3 millimeters (0.300 to 0.327in) and M10x1 metric threads. d) A tip diameter of 4.8 to 5.3 millimeters (0.190 to 0.208in) and M8x1 metric threads. e) Lengths other than approximately 25 millimeters (1in). PRO proximity probes have multiple case lengths (1.0 to 9.5 inches in 0.5 inch increments). f) Flexible stainless steel armoring attached to the probe body and extending to within 100 millimeters (4in) of the connector PRO proximity probes have optional stainless steel armoring to protect the cable attached to the probe body and extending to within 100 millimeters (4 inches) of the connector. API Standard 670, section states that the overall physical length of the probe and integral cable assembly shall be approximately 1 meter (39in), measured from the probe tip to the end of the connector. The minimum overall physical length shall be 0.8 meters (31in); the maximum overall physical length shall be 1.3 meters (51in). The integral cable length on PRO proximity probes always falls within a +30% to -0% tolerance for a 1 meter total length measured from the probe tip to the end of the connector. API Standard 670, section states that a piece of clear heat-shrink tubing (not to be shrunk at the factory) 40 millimeters (1.5in) long shall be installed over the coaxial cable before the connector is installed to assist the owner in tagging. PRO proximity probe cables have a 2 inch piece of clear polyolefin heat shrink placed over the manufacturer s part number and serial number, and an additional 2 inch piece of clear polyolefin heat shrink for the end user s private or internal labeling. 2. Extension Cables: Figure #4 Extension Cable Connection Technology Center, Inc. 5

8 API Standard 670, section states that extension cables shall be coaxial, with connectors as specified in The nominal physical length shall be 4 meters (158in) and shall be a minimum of 3.6 meters (140in). Shrink tubing shall be provided at each end in accordance with PRO extension cables have a tolerance of 4.0 meters +20% and 4.0 meters -0%. In accordance with , PRO provides two additional 2 inch pieces of clear polyolefin heat shrink for the end user s private or internal labeling. API Standard 670, section states that the attached connectors shall meet or exceed the mechanical, electrical, and environmental requirements specified in Section 4 and in MIL-C C and MIL-C-39012/5F. The cable and connector assembly shall be designed to withstand a minimum tensile load of 225 Newtons (50 pounds). PRO provides connectors with gold plated brass bodies, Teflon insulators and gold plated center contacts in accordance with MIL-C Connectors are tested under tensile loads up to 75 pounds. 3. Driver (oscillator demodulator): Driver DIN Rail Mount Panel Mount Figure #5 API Standard 670, section states that the standard oscillator-demodulator shall be designed to operate with the standard probe as defined in and the probe extension cable as defined in API Standard 670 sections states that the oscillator-demodulator output shall be 7.87 millivolts per micrometer (200 millivolts per mil) with a standard supply voltage of -24 volts DC. The oscillator-demodulator shall be calibrated for the standard length of the probe assembly and extension cable. The output, common, and power-supply connections shall be heavy-duty, corrosion-resistant terminations suitable for at least 18 American Wire Gage (AWG) wire (1.0 square Connection Technology Center, Inc. 6

9 millimeters cross section). The oscillator-demodulator shall be electrically interchangeable in accordance with for the same probe tip diameter. The interface or noise of the installed system (including oscillator-demodulator radiofrequency output noise, line-frequency interference, and multiples thereof) on any channel shall not exceed 20 millivolts pp, measured at the monitor inputs and outputs, regardless of the condition of the probe or the gap. The transducer system manufacturer's recommended tip-to-tip spacing for probe cross-talk must be maintained. The oscillator-demodulator common shall be isolated from ground. Oscillator-demodulators shall be mechanically interchangeable. PRO drivers (oscillator demodulators) have a sensitivity of 200 millivolts per mil (7.87 millivolts per micrometer) when calibrated with standard probes using a 4140 steel target. Screw terminals on the driver (oscillator-demodulator) allow for connection to a -24V power supply using wires of at least 18 AWG. The driver (oscillator-demodulator) is calibrated for the combined cable length of the probe assembly and extension cable (5 meter or 9 meter). The driver (oscillatordemodulator) is electrically interchangeable for the same probe tip diameter and total system length. The driver (oscillator-demodulator) common is isolated from ground. The driver (oscillator-demodulator) is mechanically interchangeable. API Standard 670, section states that when specified, oscillatordemodulators shall be supplied with a DIN rail mounting option. PRO provides drivers (oscillator-demodulators) with multiple mounting options, the standard and most common being the DIN Rail mounting option as shown in Figure #5. Accuracy: API Standard 670, section states that accuracy of the transducer system and monitor system in the testing (0ºC to 45ºC) and operating (-35ºC to 120ºC) temperature ranges shall be: a) The Incremental Scale Factor (ISF) error is the maximum amount the scale factor varies from 7.87 mv per micrometer (200 mv per mil) when measured at 250 µm (10 mil) increments. ISF error is associated with errors in radial vibration measurements. Within testing range, +/- 5% of 7.87 mv/µm (200 mv/mil) Outside testing range but within operating range, an additional +/- 5% of the testing range accuracy. b) The Deviation from Straight Line (DSL) error is the maximum error (in mils) in the probe gap reading at a given voltage compared to a 7.87 mv per micrometer (200 mv per mil) best fit straight line. DSL errors are associated with errors in axial position or probe gap measurements. Connection Technology Center, Inc. 7

10 Within testing range, +/ µm (+/- 1 mil) of the best fit straight line at a slope of 7.87 mv/µm (200 mv/mil) Outside testing range but within operating range, +/- 76 um (+/- 3 mils) of the best fit straight line at a slope of 7.87 mv/um (200 mv/mil) c) The Minimum Linear Range shall be 2 millimeters (80 mils). The ISF Error of PRO proximity probe systems is illustrated in Figure #6, and complies with the API Standard 670 testing range. Incremental Scale Factor (ISF) Error mm % 5% Percent 0% 5% 10% mils Figure #6 ISF Error The DSL Error of PRO proximity probe systems is illustrated in Figure #7, and complies with the API Standard 670 testing range. Deviation Straight Line (DSL) Error mm mils 0 0 μm mils Figure #7 DSL Error Connection Technology Center, Inc. 8

11 The gap to voltage Linear Range of PRO proximity probe systems is illustrated in Figure #8, and exceeds the API Standard 670 testing range. Linearity Gap (mm) Output (DC Volts) Gap (mils) Figure #8 Gap to Voltage Linear Range API Standard 670, section states that if monitoring system components or transducer system components will be used in applications exceeding the requirements of the testing or operating ranges, the machinery protection hardware vendor shall supply documentation showing how the accuracy is affected or suggest alternative transducer and monitor components suitable for the intended application. PRO would consider this on a case by case basis and provide accurate data sheets based on the application or suggest an alternative measurement. API Standard 670, section states that the proximity probe transducer system accuracy shall be verified on the actual probe target area or on a target with the same electrical characteristics as those of the actual probe target area. Connection Technology Center, Inc. 9

12 PRO component systems are calibrated to 4140 steel, unless a custom calibration based on an alternative material is requested at the time of customer order. API Standard 670, section states that when verifying the accuracy of any individual component of the proximity probe transducer system in the operating range, the components not under test shall be maintained within the testing range. PRO proximity probes, extension cables, and drivers (oscillator demodulators) are all tested at the extended temperature ranges within the guidelines of API Standard 670. Summary: API Standard 670 is a well written and meaningful guideline for use with fluid film bearing applications. In a fluid film bearing, the shaft rotation is supported by a lubricant in the bearing sleeve allowing the shaft to freely vibrate and seek a centerline that may very well not be the geometric center of the bearing sleeve. Following the guidelines of API Standard 670, proximity probes can be installed 90 o apart in the radial X & Y locations of the bearing to measure the vibration and the shaft centerline location. The vibration of the shaft will be measured as a variable DC voltage that simulates an AC vibration signal. This measurement is typically made in mils peak to peak or µm peak to peak. The radial vibration measurement can be used to quantify the total amount of shaft vibration in the X and Y directions. In many applications these two measurements are combined to form a shaft orbit plot as shown in Figure #9. The shaft orbit that is developed by combining the X & Y measurements of the radial proximity probes can be used to measure the total vibration of the shaft centerline as it rotates in the bearing sleeve. The orbit will provide the peak to peak displacement and direction of vibration relative to the shaft centerline. Figure #9 Shaft Orbit Connection Technology Center, Inc. 10

13 The location of the shaft centerline in the bearing sleeve can also be measured with the radial proximity probes. This DC voltage (gap) measurement is typically expressed in mils or µm and is an actual measurement of the spacing between the shaft surface and tip of the proximity probe. This measurement is critical in knowing the location of the shaft in the bearing sleeve, and preventing metal to metal contact between the shaft and the bearing sleeve. Alternatively, proximity probes can also be used to measure the axial shaft position (thrust), rotational speed, keyway phase reference, case expansion, and in a reciprocating machine, piston rod drop. All of these critical measurements require proximity probes, extension cables, and drivers (oscillator-demodulator) that are robust and accurate as described in API Standard 670. The PRO Standard of meeting or exceeding the requirements of API Standard 670 will provide the user with: Proximity probes that are manufactured with a resilient polyphenylene sulfide (PPS) tip, stainless steel body, Teflon jacketed cable and gold plated connectors to provide robust non-contact displacement sensors, capable of performing in harsh environments. Teflon jacketed extension cables provide connectors with gold plated brass bodies, Teflon insulators and gold plated center contacts in accordance with MIL-C Connectors are tested under tensile loads up to 75 pounds. Drivers (oscillator demodulators) that have a sensitivity of 200 millivolts per mil (7.87 millivolts per micrometer) when calibrated with standard probes using a 4140 steel target. Screw terminals on the driver (oscillatordemodulator) allow for connection to a -24V power supply using wires of at least 18 AWG. The driver (oscillator-demodulator) is calibrated for the combined cable length of the probe assembly and extension cable. An ISF error less than +/-5% of 200 mv/mil (7.87 mv/µm) when measured at 10 mil (250 µm) increments. A DSL error less than +/- 1 mil (+/ µm) of the best fit straight line at a slope of 200 mv/mil (7.87 mv/µm). A Linear Range exceeding 80 mils (2 mm). PRO and Bently TM compatible Proximity Probes, Extension Cables, and Drivers (Oscillator-Demodulators) that meet or exceed the criteria established by API Standard 670. Connection Technology Center, Inc. 11

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15 DX3301 Series BENTLY TM COMPATIBLE 8 mm Eddy Current / Proximity Probes Standard Cable Shown Armored Cable Shown Product Features Protects fluid bearing machines, such as turbines and compressors. Proprietary design makes our probes compatible with industry standards Kits Available Includes: DX3301 (Proximity Probe) DX (Extension Cable) DX (Driver) Example Kit Part Number : KT-DX A 8 mm probe tip diameter with 3/8-24 threaded body Probe tip and body sealed to prevent leaking through cable Stainless steel probe body and jam nuts Specifications Temperature Range: - 31º F (-35º C) to 350º F (177º C) Sensitivity mv/mil (8 V/mm) (1 mil = ) Wrench flats at cable end of probe body Miniature threaded connector Teflon jacketed cable Section 6 - PRO LINE DX3301 Series Ordering Information Note: Please specify individual components when ordering kits DX Case Thread No Thread Length Case Length Total Length Connector Regulatory Approval 01 = 3/8-24 No Armor 02 = 3/8-24 Armor 00 = 0.0 in 05 = 0.5 in AA 40 = 4.0 in 50 = 5.0 in 10 = 1.0 in 15 = 1.5 in BB CC 50 = 5.0 in 60 = 6.0 in 05 = 0.5 meter 10 = 1.0 meter 01 = mini coax, with connector protector 00 = None 10 = 1.0 in 60 = 6.0 in 20 = 2.0 in 70 = 7.0 in 50 = 5.0 meter 02 = mini coax 20 = 2.0 in 70 = 7.0 in 30 = 3.0 in 80 = 8.0 in 90 = 9.0 meter 30 = 3.0 in 80 = 8.0 in NOTE: 0.5 in. Increments up to 1 in. less than the case length 40 = 4.0 in 90 = 9.0 in 95 = 9.5 in Example Part Number: DX No armor, 0.5 inch thread length, 1.0 inch case length, 0.5 meter total length, mini-coax connector Lifetime Warranty on Materials & Workmanship Page

16 DX Series BENTLY TM COMPATIBLE Extension Cable Standard Cable Shown Armored Cable Shown Connector Protector Option Section 6 - PRO LINE DX Series Protective Adhesive Gel Option Kits Available Includes: DX3301 (Proximity Probe) DX (Extension Cable) DX (Driver) Example Kit Part Number : KT-DX A Product Features Bently Compatible DX extension cables match with DX3301 series probes and DX drivers to form a complete assembly to monitor vibration and shaft position Matched with Bently Compatible probes and driver assemblies for cost effective and reliable measurements Excellent chemical resistance Protective sleeves to cover connections (optional) Specifications Temperature Range : -31º F (- 35º C) to 350º F (177º C) Connector pull strength > 50 lbs. Matched to 5 & 9 meter system lengths Male & Female miniature threaded connectors Teflon jacketed cable Ordering Information Note: Please specify individual components when ordering kits - - DX System Length (reference only) Total Length of Extension Cable Armor Regulatory Approval 50 = 5.0 m 000 = 0.0 m 00 = No 00 = None 90 = 9.0 m 040 = 4.0 m 01 = Yes 045 = 4.5 m 080 = 8.0 m 085 = 8.5 m 02 = No, with connector protector 03 = Yes, with connector protector Example Part Number: DX meter total cable length, No armor Lifetime Warranty on Materials & Workmanship Page 2

17 DX Series BENTLY TM COMPATIBLE Driver Assembly DIN Rail Option (Shown Below) Panel Mount Option (Shown Above) Product Features Driver assembly DX offers multiple options for mounting and easy connections via BNC jack and screw terminals Kits Available Includes: DX3301 (Proximity Probe) DX (Extension Cable) DX (Driver) Example Kit Part Number : KT-DX A Flexible system configuration DC gap and shaft vibration signals available via BNC jack for analysis Multiple mounting options (DIN rail, panel or none) Specifications Temperature Range : - 31º F (- 35º C) to 185º F (85º C) Linear Range - 10 to 90 mils ( approximately -1 to -17 Vdc Aluminum Enclosure with powder coated finish Miniature threaded connector 3 position screw terminals + BNC output Section 6 - PRO LINE DX Series Ordering Information DX Note: Please specify individual components when ordering kits System Length Mounting Type Regulatory Approval 5 = 5.0 meter 9 = 9.0 meter 0 = Panel 1 = DIN 2 = None 00 = None Example Part Number: DX meter system length, DIN mount Lifetime Warranty on Materials & Workmanship Page

18 DP Series Reverse Mount 8 mm Eddy Current / Proximity Probes Standard Cable Shown "CC" 0.14 Tip Diam. 8mm Product Features.44 in (11 mm) Protects fluid bearing machines, such as turbines and compressors. Proprietary design makes our probes compatible with industry standards Section 6 - PRO LINE DP Series Kits Available Includes: DP1001 (Proximity Probe) DC1001 (Extension Cable) DD1001 (Driver) Example Kit Part Number : KT-DA mm probe tip diameter with 3/8-24 threaded body Probe tip and body sealed to prevent leaking through cable Stainless steel probe body Specifications Temperature Range: - 31º F (-35º C) to 350º F (177º C) Sensitivity mv/mil (8 V/mm) (1 mil = ) Miniature threaded connector Teflon jacketed cable Ordering Information Note: Please specify individual components when ordering kits CC DP Case Thread No Thread Length Case Length Total Length Connector Regulatory Approval 05 = reverse mount with 3/8-24 threaded body 02 = 0.2 in 12 = 1.2 in 05 = 0.5 meter 10 = 1.0 meter 50 = 5.0 meter 90 = 9.0 meter 02 = mini coax 00 = None Example Part Number: DP Reverse mount with 3/8-24 threaded body, 0.2 inch no thread length, 1.2 inch case length, 0.5 meter total length, mini coax Lifetime Warranty on Materials & Workmanship Page 4

19 DP1001 Series 8 mm Eddy Current / Proximity Probes Standard Cable Shown Armored Cable Shown Product Features Protects fluid bearing machines, such as turbines and compressors. Proprietary design makes our probes compatible with industry standards Kits Available Includes: DP1001 (Proximity Probe) DC1001 (Extension Cable) DD1001 (Driver) Example Kit Part Number : KT-DA mm probe tip diameter with 3/8-24 threaded body Probe tip and body sealed to prevent leaking through cable Stainless steel probe body and jam nuts Specifications Temperature Range: - 31º F (-35º C) to 350º F (177º C) Sensitivity mv/mil (8 V/mm) (1 mil = ) Wrench flats at cable end of probe Miniature threaded connector Teflon jacketed cable Section 6 - PRO LINE DP1001 Series Ordering Information Note: Please specify individual components when ordering kits DP Case Thread No Thread Length Case Length Total Length Connector Regulatory Approval 01 = 3/8-24 No Armor 02 = 3/8-24 Armor 00 = 0.0 in 05 = 0.5 in AA 40 = 4.0 in 50 = 5.0 in 10 = 1.0 in 15 = 1.5 in BB CC 50 = 5.0 in 60 = 6.0 in 05 = 0.5 meter 10 = 1.0 meter 01 = mini coax, with connector protector 00 = None 10 = 1.0 in 60 = 6.0 in 20 = 2.0 in 70 = 7.0 in 50 = 5.0 meter 02 = mini coax 20 = 2.0 in 70 = 7.0 in 30 = 3.0 in 80 = 8.0 in 90 = 9.0 meter 30 = 3.0 in 80 = 8.0 in 40 = 4.0 in 90 = 9.0 in 95 = 9.5 in Example Part Number: DP No armor, 0.5 inch no thread length, 1.0 inch case length, 0.5 meter total length, mini coax with connector protector, Lifetime Warranty on Materials & Workmanship Page

20 DC1001 Series Extension Cable Standard Cable Shown Armored Cable Shown Connector Protector Option Product Features PRO DC1001 extension cables mate with probes and drivers to form a complete assembly to monitor vibration and shaft position Section 6 - PRO LINE DC1001 Series Protective Adhesive Gel Option Kits Available Includes: DP1001 (Proximity Probe) DC1001 (Extension Cable) DD1001 (Driver) Example Kit Part Number : KT-DA1001 Matched with PRO probes and driver assemblies for cost effective and reliable measurements Excellent chemical resistance Protective sleeves to cover connections (optional) Specifications Temperature Range : -31º F (- 35º C) to 350º F (177º C) Connector pull strength > 50 lbs. Matched to 5 & 9 meter system lengths Male & Female miniature threaded connectors Teflon jacketed cable Ordering Information Note: Please specify individual components when ordering kits - - DC System Length (reference only) Total Length of Extension Cable Armor Regulatory Approval 50 = 5.0 m 000 = 0.0 m 00 = No 00 = None 90 = 9.0 m 040 = 4.0 m 01 = Yes 045 = 4.5 m 080 = 8.0 m 085 = 8.5 m 02 = No, with connector protector 03 = Yes, with connector protector Example Part Number: DC meter total length, no armor Lifetime Warranty on Materials & Workmanship Page 6

21 DD1001 Series Driver Assembly DIN Rail Option (Shown Below) Panel Mount Option (Shown Above) Product Features Driver assembly DD1001 offers multiple options for mounting and easy connections via BNC jack and screw terminals Kits Available Includes: DP1001 (Proximity Probe) DC1001 (Extension Cable) DD1001 (Driver) Example Kit Part Number : KT-DA1001 Flexible system configuration DC gap and shaft vibration signals available via BNC jack for analysis Multiple mounting options (DIN rail, panel or none) Specifications Temperature Range : - 31º F (- 35º C) to 185º F (85º C) Linear Range - 10 to 90 mils ( approximately -1 to -17 Vdc Aluminum Enclosure Miniature threaded connector 3 position screw terminals + BNC output Section 6 - PRO LINE DD1001 Series Ordering Information DD Note: Please specify individual components when ordering kits System Length Mounting Type Regulatory Approval 5 = 5.0 meter 9 = 9.0 meter 0 = Panel 1 = DIN 2 = None 00 = None Example Part Number: DD meter system length, DIN mount Lifetime Warranty on Materials & Workmanship Page

22 DM901-1A DM903-1A 1/2 14 NPT mounting bushing for 3/8-24 probe bodies 3/4 14 NPT with conduit connection 3/8-24 UNF - 2B 3/4-14 NPT 3/4-14 NPT 3/8-24 UNF - 2B 1/2-14 NPT 0.25 in [6 mm] 1.00 in [25 mm] 0.75 in [19 mm] 1.00 in [25 mm] 1.00 in [25 mm] DM902-1A Aluminum proximity probe mount, non-clamping version, with 3/8-24 threaded hole 1.25 in [32 mm] 1.75 in [44 mm] DM902-2A Aluminum proximity probe mount, clamping version, with clearance hole for 3/8-24 threaded probe case R0.19 in [5 mm] 3/8-24 UNF - 2B 0.75 in [19 mm] 0.75 in [19 mm] 0.50 in [13 mm] n0.20 in DM902-1B Phenolic proximity probe mount, non-clamping version, with 3/8-24 threaded hole n0.20 in 0.50 in [13 mm] [5 mm] 1.25 in [32 mm] Proximity Probe Mounting Hardware Section 6 - PRO LINE Proximity Probe Mounting Hardware [5 mm] 1.25 in [32 mm] DM902-2B Phenolic proximity probe mount, clamping version, with clearance hole for 3/8-24 threaded probe case Proximity Probe Mounting Diagram DM902-2B Shown Correct Mounting Orientation Note: Mounting Bolts Not Included Lifetime Warranty on Materials & Workmanship Page 8

23 Proximity Probe Mounting Options Executive Summary This edition of CTC s PRO APPnotes will discuss the three primary methods for mounting proximity or eddy current probes for radial measurements. Monitoring of journal bearings Proximity probes are often used to monitor (also known as turbine shafts in power plants. sleeve bearings or plain bearings) is generally accomplished by using "eddy current" or "proximity" probes. These probes use the fluctuations induced in an electromagnetic field generated by the probe to determine the bearing shaft position relative to the bearing casing and the dynamic vibration of the rotating shaft. Proper probe mounting will have a significant effect on the validity of the data measured by the monitoring system. In general two probes mounted 90 degrees apart are the most commonly used configuration for mounting radial proximity probes. Each probe monitors the position of the shaft relative to the X or Y location. DP1001 and DX3301 series probes are recommended for most applications. There are three primary methods of mounting the probes, internally mounted, through mount (internal/external), where the probes are mounted through the bearing casing and the casing is counter bored to prevent the probe from side sensing; and externally mounted, where the probes are mounted on the outside of the machine and measure an exposed portion of the shaft. 1. Internal mounting. By mounting the eddy current probes completely inside the machine or bearing housing with PRO DM902 series brackets (or with custom designed and manufactured brackets) three things are accomplished, the probe measures the shaft surface, the costs of installation are minimized, and the measurement of the shaft position and vibration is very precise. Advantages/Disadvantages: The probes must be installed and properly spaced before the bearing cover is reinstalled. An accommodation must be made for the probe cable to exit the bearing housing. This can be accomplished by using an existing plug or fitting, or by drilling and tapping a hole above the oil line and properly sealing to avoid leaks. The cables must also be tied down inside the bearing housing to prevent cable damage or failure from contact with the shaft. On the down side there is no access to the probe at all when the machine is running, all fasteners inside the bearing housing should be safety wired, or otherwise prevented from working loose inside the machine, and extra care must be taken at the cable exits to prevent leakage. 2. Through mounting. Through mounting (sometimes called internal/external), is where the probe is mounted through the bearing casing and the casing is counter bored to prevent the probe from side sensing or providing false readings from the bearing housing. Internal/external mounting is accomplished when an appropriately sized hole is drilled and tapped directly through the bearing housing or the proximity probes are mounted with a Mounting Adapter Bushing like PRO s DM901 and DM903 series. These adapters allow external access to the probe but allows the probe tip to be internal to the machine or bearing housing. Advantages/ Disadvantages: Care must be taken in drilling and tapping the bearing housing or cover to insure that the probes will be perpendicular to the shaft center line. The benefits of this standard mounting include the ability to replace or adjust the probes without disassembly of the bearing and the location usually offers a good viewing area for the probe. 3. External mounting. External proximity probe mounting is typically used when other methods are not available. Special care must be given to the quality of the shaft surface and mechanical protection of the exposed probes and cables is required. Advantages/Disadvantages: Exposed areas of the shaft may have scuffing, scratching or rust limit the measurement 90 O Shaft Bearing Housing External mounting probe diagram quality of the probes. If the shaft is inspected and found to be clean and smooth then this location may be used for measurement. The advantages of this mounting style are the low cost and the easy access to the probes. Parts included in this discussion DM901, DM902, & DM903 Proximity probe mounting options DP1001 Series proximity probes, cables and drivers DX3301 Series Bently compatible proximity probes, cables and drivers. If you have any questions or for further information please contact CTC directly via at dgripe@ctconline.com or sales@ctconline.com or feel free to call in the US and Canada or internationally.

24 Proximity Probe Mounting - Thrust Measurements Executive Summary One of the issues for reliability professionals in the current era is how to effectively and reliably monitor thrust bearing wear in critical applications. This edition of CTC s PRO AppNotes will explore the concept of axial monitoring of plain or journal bearings on assets such as turbines for increased reliability and safety. The axial or thrust position is one of the most critical measurements in rotating machinery. If a thrust bearing should fail, axial movement of the shaft is no longer constrained and must instead be translated to some other part of the machine. When this is allowed to occur, the uncontrolled axial movement will quickly allow rotating and non-rotating elements to come in contact, resulting in disastrous consequences. Such regrettable occurrences are financially devastating for the asset and can also be a serious safety risk to plant personnel. While some degree of reliability can be achieved using a single proximity probe to monitor the thrust position, virtually all the guidelines and standards for reliability (including API Standard 670) agree that dual probes should be used to achieve the greatest Probes are important monitoring tools for all types of turbines the proximity probe units fails. Proximity probes are often used to monitor turbine shafts in power plants. reliability. Dual probe systems provide redundancy to ensure continued measurement integrity in the event one of Preparing for installation Several important measurement techniques must be decided upon prior to installation and calibration of the system. These techniques should remain in consistent use throughout the plant. The most common thrust position full scale range selected is usually +40 to 40 mils (which falls within the PRO proximity probe systems normal range of 90 mils). Positioning is important as well. The most common recommendation is that proximity probes used to monitor thrust position be placed within two (2) shaft diameters of the thrust bearing (for example 4on a 4 inch diameter shaft the probes should be mounted no further than 8 inches from the thrust collar). This assures that the proximity probe system is not adversely affected by shaft thermal growth. In some cases this is not possible, and the analysts needs to be aware of the thermal growth expected and plan accordingly. Installation Special brackets or housings may be required to achieve correct probe positioning and adjustment. However, frequently probes can be mounted through the bearing casing using PRO s DM901 and DM903 series probe mounting adapters. Where probes cannot be mounted directly monitoring the shaft they can sometimes be mounted to observe the thrust collar or some other integral axial shaft surface. Once the Monitoring a thrust bearing collar with a dual probe installation. Dual axial probes mounted with DM901-1A bushings probes are installed correctly they must then be properly gapped. Extreme care must be taken when this step is performed. Improper gapping results in the permissible range of the thrust bearing falling outside of the probe s linear measurement range. In order to properly gap the probe the shaft is mechanically barred against the active thrust shoe or other known position. The proximity probe can then be gapped and the DC voltage documented. In order to insure the proper placement of the probe a worksheet incorporating the allowable shaft wear, float zone and probe parameters should be developed. This will help determine the optimum gap and that all alarms fall with in the probes measurement range. Parts included in this discussion DM901, DM902, & DM903 Proximity probe mounting options DP1001 Series proximity probes, cables and drivers DX3301 Series Bently compatible proximity probes, cables and drivers. If you have any questions or for further information please contact CTC directly via at dgripe@ctconline.com or sales@ctconline.com or feel free to call in the US and Canada or internationally.

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