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1 PRECISION RING DRIVE SYSTEMS Based on Nexen s innovative Roller Pinion technology, Nexen Ring Drive Systems come complete with a precision grade, high capacity bearing and drive mechanism in a rigid housing. With options for high speed, high torque and zero backlash, Nexen Ring Drives can be optimized for every application. With accelerations up to twice as high as other indexing technologies, Nexen Ring Drive systems provide more productivity while boasting low maintenance, high efficiency and long life. Features & Benefits... 2 Selection Process... 4 Compact Precision Ring Drive (CRD): Timing Diagrams... 6 Load Diagrams... 8 System Life Dimensions Specifications Direct Drive Motor Accessories: Brake Precision Ring Drive (PRD): Timing Diagrams Load Diagrams Dimensional Drawing... 2 Specifications PATENTED Courtesy of Steven Engineering, Inc - (8) sales@steveneng.com -

2 The Nexen Ring Drive Advantage Based on Nexen s innovative Roller Pinion technology, Nexen Ring Drive (CRD & PRD) systems come complete with a precision grade bearing and drive mechanism in a rigid housing to simplify the selection process. With all the great features of our other advanced RPS technology, the Ring Drives open up new design possibilities to next generation machines. High Indexing Precision With an indexing precision up to ± 11 ArcSec and repeatability up to ± 1.2 ArcSec, Nexen s Ring Drives offer unmatched mechanical system capabilities. Zero Backlash Unlike other mechanical drive systems, the CRD offers zero backlash options from the motor through the driven load. High Load Capacity With the precision grade, high load capacity cross-roller bearing, Nexen Ring Drives can handle loads up to 1575 kn. High Speed Nexen Ring Drives can handle speeds up to 225 RPM. Unlike traditional cam driven systems, Nexen Ring Drives can handle peak torque inputs at any time. This allows for indexing times up to 2x faster than the competition. Smooth in Motion Combining Nexen's RPS technology with a preloaded cross-roller bearing and an integrated motor/precision gearhead gives a rigid, smooth system. High Torque Holding With the optional zero backlash holding brake, the CRD can hold loads up to 8 Nm (available on CRD25, larger sizes pending) while still maintaining an open center. DEPENDABLE. VERSATILE. OPTIONS THAT DELIVER. Robot Indexer Welding Trunnion Positioning Semiconductors 2 Medical Products Robotics Courtesy of Steven Engineering, Inc - (8) sales@steveneng.com -

3 CRD: A DRIVE STATION FOR EVERY APPLICATION PRD: CAPACITY EVEN FOR THE MOST DEMANDING High Precision Planetary (PL) High Torque High Speed Low Backlash Flexible Gearhead Ratio Harmonic Gearhead (HG) High Torque Low Speed Zero Backlash High Ratio Gearhead High Precision Planetary High Torque High Speed Low Backlash Flexible Gearhead Ratio Direct Drive Pinion (DD) High Speed Mid Torque Zero Backlash Integrated Motor No Gearhead Output (Dial) Plate Bolt Circle Diameters: Output (Dial) Plate Bolt Circle Diameters: 25 mm, 35 mm, 55 mm 4 mm, 75 mm, 11 mm, 15 mm Peak Output Torque: Peak Output Torque: 25 Nm, 35 Nm, 55 Nm 563 Nm, 968 Nm, 1496 Nm, 1936 Nm Positional Accuracy: Positional Accuracy: ± 2 to 59 ArcSec ± 11 to 35 ArcSec Max Backlash: Max Backlash: ± to 2.3 ArcSec ± 3 to 12 ArcSec Input to Output Speed Ratio: Input to Output Speed Ratio: 6.2:1 to 246:1 25.6:1 to 66:1 IP 65 Rated Sealed Housing Shrouded/Guarded Housing Positioning Indexer Material Fabrication Automotive 3 Aerospace Welding DEPENDABLE. RELIABLE. PERFORMANCE Indexer Courtesy of Steven Engineering, Inc - (8) sales@steveneng.com -

4 Ring Drive Selection Process Nexen will work with you to select the perfect Ring Drive for your application needs. Please fill in the application data below and perform the calculations on the following page. With this information, Nexen will select a Ring Drive system to meet all your application requirements. F axial F radial STEP 1: GATHER APPLICATION DATA Before you begin calculations, there are key measurements that you will need from your application. Collect the data and record it in the chart below. With this data available you can proceed on to the calculations on the following page. (Refer to the diagram to the right when completing the table below.) T M T O Measurements Required for Selection Customer Data (record your values below) Sample Data Load Inertia (I) kgm 2 7 kgm 2 Index Time (t I ) seconds.9 seconds Move Distance (θ) 45 Maximum Axial Load (F axial) kn 5 kn Maximum Radial Load (F radial) kn kn Maximum Moment Load (T M) knm 1 knm Drag Torque & Other Applied Torque Loads (T O) May include table support friction, cutting or clamping forces, etc. Shock Factor (K) Circle the value that best reflects the smoothness of your application. Shockless Operation Normal Operation Operation with Impact Operation with High Impact Nm Nm 1.2 Other Key Application Information Application Description: Environmental Conditions: c Typical Industrial c High Humidity c High Temperature c High Dust Positional Accuracy Requirements: Mounting Orientation: c Vertical (Radial Load) c Horizontal (Applied Load) c Horizontal (Suspended Load) 4 Courtesy of Steven Engineering, Inc - (8) sales@steveneng.com -

5 STEP 2: CALCULATING RING DRIVE REQUIREMENTS FOR SIMPLE INDEXING APPLICATIONS Ring Drive selection is based on the torque requirements of your application. Using the information gathered on the preceding page, perform the following calculations. If your application movement is more complex than basic indexing, evaluate each stage of movement independently and perform separate calculations for each stage. Acceleration Time Acceleration Time: t A = t I 2 Sample: t A =.9 seconds 2 =.45 seconds t A = sec 2 t A = sec Max Angular Speed: w = (q t I ) ( 9) w = Sample: w = (45º.9 seconds) ( 9) = 1.75 rad/sec sec 9 w = Max Angular Speed rad/sec Angular Acceleration Angular Acceleration: a = w t A a = rad/sec sec a = rad/s 2 Sample: a = 1.75 rad/sec.45 sec = 3.89 rad/s 2 Ring Gear Torque Application Torque: T gear = (I a) + T O T gear = kgm 2 rad/s 2 + Nm T gear = Nm Sample: T gear = (7 kgm rad/s 2 ) + 1 Nm = Nm Application Torque with Shock Factor: T T = T gear K T T = Nm Ring Gear Torque w/ Shock Factor T T = Nm Sample: T T = Nm 1.2 = 339 Nm STEP 3: EVALUATE LOAD CARRYING CAPACITY Use the data for Maximum Axial Load, Maximum Radial Load, Maximum Moment Load, and Mounting Orientation to evaluate your load carrying needs against the load diagrams on the following pages. To do this, find the set of charts that represents your mounting orientation, then graph your data in the appropriate charts(s) to ensure that your requirements fall into the shaded area representing load capacity available in that CRD or PRD size and orientation. (NOTE: The weight of the CRD or PRD is already factored into the load charts.) STEP 4: CHOOSE YOUR CRD SIZE Use the Application Torque with Shock Factor requirement calculated in Step 2 and the load evaluation from Step 3 to select the Ring Drive size that best fits your application. Review CRD and PRD Specifications to ensure the selected size meets all of your application requirements. Selected CRD or PRD Size 5 Courtesy of Steven Engineering, Inc - (8) sales@steveneng.com -

6 CRD Timing Diagrams CRD25-PL Timing Diagram CRD35-PL Timing Diagram * * Output Load Inertia 1. Output Load Inertia 1 kg m 2 5 kg m 2 1 kg m 2 25 kg m 2 5 kg m Output Load Inertia 1 kg m 2 5 kg m 2 1 kg m 2 25 kg m 2 5 kg m Output Load Inertia 1. 1 kg m kg m 2 1 kg m kg m kg m CRD25-HG Timing Diagram CRD35-HG Timing Diagram * * Output Load Inertia 5. 1 kg m 2 5 kg m 2 1 kg m kg m 2 Output Load Inertia 5 kg m kg m 2 5 kg m 2 1 kg m kg m 2 5 kg m Output Load Inertia 1 kg m 2 5 kg m 2 1 kg m 2 25 kg m 2 Output Load 5 Inertia kg m 2 1 kg m 2 5 kg m 2 1 kg m 2 25 kg m 2 5 kg m CRD25-DD Timing Diagram CRD35-DD Timing Diagram CRD25-DD Timing Diagram 2.5 Output Output Load Inertia Load Inertia 2. 1 kg m 2 1 kg m 2 5 kg m 2 5 kg m 2 1 kg m1 2 kg m kg m25 2 kg m 2 5 kg m5 2 kg m Output Load Inertia 1 kg m 2 5 kg m 2 1 kg m 2 25 kg m 2 5 kg m NOTES: Curves assume no external forces such as additional table support friction, cutting forces, etc. Timing diagrams are developed assuming minimum drag torque, use for reference only. Assumes Planetary Gearbox Ratio of 4:1 and Harmonic Gearhead Ratio of 5:1 (other ratio options available) * 6 Courtesy of Steven Engineering, Inc - (8) sales@steveneng.com -

7 CRD Timing Diagrams CRD55-PL Timing Diagram * Output Load Inertia 1 kg m 2 5 kg m 2 1 kg m 2 25 kg m 2 5 kg m CRD55-HG Timing Diagram * Output Load Inertia 1 kg m 2 5 kg m 2 1 kg m 2 25 kg m 2 5 kg m CRD55-DD Timing Diagram Output Load Inertia 1 kg m 2 5 kg m 2 1 kg m 2 25 kg m 2 5 kg m NOTES: Curves assume no external forces such as additional table support friction, cutting forces, etc. Timing diagrams are developed assuming minimum drag torque, use for reference only. Assumes Planetary Gearbox Ratio of 4:1 and Harmonic Gearhead Ratio of 5:1 (other ratio options available) * 7 Courtesy of Steven Engineering, Inc - (8) sales@steveneng.com -

8 CRD Load Diagrams (Applied Load) Compact Ring Drive Moment Load LOAD Axial Load CUSTOMER MACHINE FRAME MOMENT LOAD (knm) CRD25 Applied Load Chart Bearing Capacity Bolted Joint Capacity AXIAL LOAD (kn) Contact Nexen for bearing life in this orientation MOMENT LOAD (knm) CRD35 Applied Load Chart Bearing Capacity Bolted Joint Capacity AXIAL LOAD (kn) Contact Nexen for bearing life in this orientation MOMENT LOAD (knm) CRD55 Applied Load Chart Bearing Capacity Bolted Joint Capacity AXIAL LOAD (kn) Contact Nexen for bearing life in this orientation 8 Courtesy of Steven Engineering, Inc - (8) sales@steveneng.com -

9 CRD Load Diagrams (Suspended Load) CUSTOMER MACHINE FRAME Compact Ring Drive Suspended Axial Load LOAD Distance from Center DISTANCE FROM CENTER (mm) DISTANCE FROM CENTER (mm) CRD25 Suspended Load Chart (upside-down orientation) AXIAL LOAD (kn) CRD35 Suspended Load Chart (upside-down orientation) AXIAL LOAD (kn) DISTANCE FROM CENTER (mm) CRD55 Suspended Load Chart (upside-down orientation) AXIAL LOAD (kn) 9 Courtesy of Steven Engineering, Inc - (8) sales@steveneng.com -

10 CRD Load Diagrams (Radial Load) Distance from Machine Frame Radial Load LOAD Compact Ring Drive CUSTOMER MACHINE FRAME DISTANCE FROM MACHINE MOUNTING SURFACE (mm) DISTANCE FROM MACHINE MOUNTING SURFACE (mm) RADIAL LOAD (kn) RADIAL LOAD (kn) CRD25 Radial Load Chart CRD35 Radial Load Chart DISTANCE FROM MACHINE MOUNTING SURFACE (mm) RADIAL LOAD (kn) CRD55 Radial Load Chart 1 Courtesy of Steven Engineering, Inc - (8) sales@steveneng.com -

11 CRD System Life CRD life is based on average output torque and drive station options. Average Output Torque (Nm) CRD25 Life Drive Station HG PL DD Output Revolutions (Million) 16 Assumes Planetary Gearbox Ratio of 4:1 and Harmonic Gearhead Ratio of 5:1 (other ratio options available) Average Output Torque (Nm) CRD35 Life Drive Station Output Revolutions (Million) HG PL DD Assumes Planetary Gearbox Ratio of 4:1 and Harmonic Gearhead Ratio of 5:1 (other ratio options available) Average Output Torque (Nm) CRD55 Life Drive Station HG PL DD Output Revolutions (Million) Assumes Planetary Gearbox Ratio of 4:1 and Harmonic Gearhead Ratio of 5:1 (other ratio options available) 11 Courtesy of Steven Engineering, Inc - (8) sales@steveneng.com -

12 CRD Dimensions All dimensions shown in mm. Not Shown: Air Inlet Fitting for.17" I.D. Hose. (Used on Optional Brake ONLY.) A C E N F M K G H I GREASE FITTING OUTPUT MOUNTING HOLES: CRD25: M8 X 1.25 CRD35: M1 X 1.5 CRD55: M12 X 1.75 D 2 AT 18 (1 ACCESS HOLE ON UNITS WITH OPTIONAL BRAKE) BASE MOUNTING HOLES FOR CUSTOMER SUPPLIED SCREWS: CRD25: M8 CRD35: M1 CRD55: M1 J.5 L NOTE: Basic dimensions shown for selection purposes only and subject to change. Visit for detailed drawings and CAD models before designing into your system. * CRD25 CRD35 CRD55 A Drive Station Envelope to Center Distance B Drive Station Envelope Width C Outer Diameter D Stationary Bolt Circle Diameter E Output Bolt Circle Diameter F Base Mounting Hole Circle Diameter G Output Outer Diameter H Output Inner Diameter (H7) I Inner Diameter without Brake with Brake 31.7 N/A N/A J Depth to Stationary Ring K Overall Length L Unit Height M N O Drive Station Center to CRD Center Drive Station & Adapter Width Drive Station Depth * PL, HG DD PL, HG DD PL HG DD Not present on units with optional brake. 12 Courtesy of Steven Engineering, Inc - (8) sales@steveneng.com -

13 CRD Specifications High Torque & High Speed High Torque & Low Speed High Speed & Mid Torque Performance Specifications CRD25-PL CRD35-PL CRD55-PL CRD25-HG CRD35-HG CRD55-HG CRD25-DD CRD35-DD CRD55-DD Maximum Velocity RPM (2) 18 (2) 11 (2) See Charts See Charts See Charts Max Continuous Velocity RPM 151 (2) 111 (2) 7 (2) 18 (2) 13 (2) 8 (2) See Charts See Charts See Charts Positional Accuracy (3) ±ArcSec 59 (1) 43 (1) 27 (1) One Way Repeatability (3) ±ArcSec Max Backlash ArcSec 2.3 (1) 14.8 (1) 9.4 (1) Max Acceleration Torque Nm Continuous Stall Torque Nm N/A N/A N/A N/A N/A N/A Nominal Torque Nm N/A N/A N/A Gear/Pinion Ratio 3.8:1 5.2:1 8.2:1 3.8:1 5.2:1 8.2:1 6.2:1 8.4:1 13:1 Input to Output Ratio 15.2:1 (2) 2.8:1 (2) 32.8:1 (2) 19:1 (2) 26:1 (2) 41:1 (2) 6.2:1 8.4:1 13:1 Min Drag Torque (no load) Nm Max Load Inertia kgm 2 N/A N/A N/A N/A N/A N/A Output Inertia kgm Total Reflected Inertia to kgm Gearbox Output (4).138 (4).294 (4) (1) Includes Gearbox Backlash (2) Assumes Planetary Gearbox Ratio of 4:1 and Harmonic Gearhead Ratio of 5:1 (other ratio options available) (3) Contact Nexen for higher precision options (4) Total Reflected Rotary Inertia, including Motor Inertia CRD Output Drag Torque The CRD s output drag torque consists of seal drag and bearing drag. Bearing drag is directly affected by any axial, radial, and moment loading applied to the output of the CRD. Depending on the application, bearing drag torque can be a significant factor and difficult to calculate. For this reason, please contact Nexen for assistance with estimating bearing drag torque when applying load to the output of the CRD. CRD Direct Drive Motor Specifications Peak Speed Torque Curves at Output 4 CRD25-DD 6 CRD35-DD Output Torque (Nm) Supply Voltage 48 VAC 4 VAC 23 VAC Output Torque (Nm) Supply Voltage 48 VAC 4 VAC 23 VAC Output RPM Output RPM Output Torque (Nm) VAC 2 4 VAC 23 VAC Output RPM Supply Voltage CRD55-DD * For non-cyclic continuous operation, contact Nexen. 13 Courtesy of Steven Engineering, Inc - (8) sales@steveneng.com -

14 CRD Direct Drive Motor Direct Drive Motor Specifications Specifications CRD25-DD CRD35-DD CRD55-DD Voltage Req d at Rated Output (Vac Input) Vac Peak Current (lp) (1) Arms Continuous Stall Current (lc) (2) Arms Torque Sensitivity (Kt) (3) Nm/Arms Back EMF Constant (Kb) (3) Vrms/kRPM Resistance (Line to Line) (Rm) Ohms Inductance (Lm) mh Motor Poles C winding temperature (2) Winding temperature = 145 continuous stall, 25 C ambient (3) System Equivalent Values Motor Feedback CRD Feedback Specifications ENDAT1 Output Interface Endat 2.1 Multi-turn Device Resolution Cycles or Lines/Rev 248 Resolution after AKD Interpolation Counts 134, 217, 728 Input Voltage VDC ±5% 5 Current Consumption ma Max 25 Plug and Play Motor ID * *These feedback devices include electronic motor nameplate data allowing plug-andplay commissioning, eliminating the need for drive parameter set-up and servo loop tuning in most applications. Yes 14 Courtesy of Steven Engineering, Inc - (8) sales@steveneng.com -

15 CRD Accessories: Brake Optional Holding Brake Nexen offers an optional holding brake that acts directly on the CRD driven output. (Available on CRD25, larger sizes pending.) With spring engaged / air released braking action, the brake s compact design does not increase the CRD footprint and maintains an open center. For brake E-Stop capabilities, contact Nexen. Brake Actuates Radially to Hold on Output Fits Inside CRD CRD Brake Specifications CRD25B Holding Torque Nm 8 Release Pressure psi 6 Brake Life Brake Torsional Rigidity Cycles Nm / Radian 1 million 8.65 million Note: Brake can be manually released by inserting screws into holes on its bottom side. Note: Brake is fully sealed and IP 65 rated. 15 Courtesy of Steven Engineering, Inc - (8) sales@steveneng.com -

16 PRD Timing Diagrams PRD4 Timing Diagram kg m 2 5 kg m 2 1 kg m 2 25 kg m 2 5 kg m PRD75 Timing Diagram kg m 2 5 kg m 2 1 kg m 2 25 kg m 2 5 kg m PRD11 Timing Diagram kg m 2 5 kg m 2 1 kg m 2 25 kg m 2 5 kg m PRD15 Timing Diagram kg m 2 5 kg m 2 1 kg m 2 25 kg m 2 5 kg m NOTE: Curves assume no external forces such as additional table support friction, cutting forces, etc. 16 Courtesy of Steven Engineering, Inc - (8) sales@steveneng.com -

17 PRD Load Diagrams (Applied Load) Precision Ring Drive Moment Load LOAD Axial Load CUSTOMER MACHINE FRAME PRD4 Applied Load Chart PRD75 Applied Load Chart PRD11 Applied Load Chart PRD15 Applied Load Chart MOMENT LOAD (knm) MOMENT LOAD (knm) MOMENT LOAD (knm) MOMENT LOAD (knm) AXIAL LOAD (kn) 9 8 Bearing Capacity 7 Bolted Joint Capacity AXIAL LOAD (kn) AXIAL LOAD (kn) Bearing Capacity Bolted Joint Capacity Bearing Capacity Bolted Joint Capacity Bearing Capacity Bolted Joint Capacity AXIAL LOAD (kn) 17 Courtesy of Steven Engineering, Inc - (8) sales@steveneng.com -

18 PRD Load Diagrams (Suspended Load) CUSTOMER MACHINE FRAME Suspended Axial Load LOAD Precision Ring Drive Distance from Center PRD4 Suspended Load Chart (upside-down orientation) PRD75 Suspended Load Chart (upside-down orientation) 2 2 DISTANCE FROM CENTER (mm) DISTANCE FROM CENTER (mm) SUSPENDED AXIAL LOAD (kn) SUSPENDED AXIAL LOAD (kn) PRD11 Suspended Load Chart (upside-down orientation) PRD15 Suspended Load Chart (upside-down orientation) 2 2 DISTANCE FROM CENTER (mm) DISTANCE FROM CENTER (mm) SUSPENDED AXIAL LOAD (kn) SUSPENDED AXIAL LOAD (kn) NOTE: The weight of the PRD is already factored into these charts. 18 Courtesy of Steven Engineering, Inc - (8) sales@steveneng.com -

19 PRD Load Diagrams (Radial Load) 2 Distance from Machine Frame Radial Load LOAD Precision Ring Drive CUSTOMER MACHINE FRAME NOTE: The weight of the PRD is already factored into charts. DISTANCE FROM MACHINE MOUNTING SURFACE (mm) DISTANCE FROM MACHINE MOUNTING SURFACE (mm) DISTANCE FROM MACHINE MOUNTING SURFACE (mm) DISTANCE FROM MACHINE MOUNTING SURFACE (mm) RADIAL LOAD (kn) RADIAL LOAD (kn) RADIAL LOAD (kn) RADIAL LOAD (kn) PRD4 Radial Load Chart PRD75 Radial Load Chart PRD11 Radial Load Chart PRD15 Radial Load Chart 19 Courtesy of Steven Engineering, Inc - (8) sales@steveneng.com -

20 PRD Dimensions 25. A 9.5 B G Dial Plate MountingHole M12 x 1.75 C ø118. Gearbox input configured to fit customer motor Base Mounting Holes for customer supplied M12 screws Dial plate not supplied with system D E F mm dowel pin hole pattern for dial plate pilot (customer provided) min. thickness of customer supplied dial plate H I (112) NOTE: Basic dimensions shown for selection purposes only and subject to change. Visit for detailed drawings and CAD models before designing into your system. (All dimensions shown in mm.) PRD4 PRD75 PRD11 PRD15 A Minimum Outer Diameter B Maximum Inner Diameter C Base Mounting Hole Circle Diameter D Dial Plate Bolt Pattern Circle Diameter E Ring Drive Pilot Diameter F Dowel Pin Hole Circle For 6mm Pins G Drive Enclosure Envelope to Center Distance H Minimum Depth to Dial Plate Pilot I Maximum Depth to Dial Plate Pilot Courtesy of Steven Engineering, Inc - (8) sales@steveneng.com -

21 PRD Specifications Performance Specifications PRD4 PRD75 PRD11 PRD15 Positional Accuracy* ±ArcSec One Way Repeatability* ±ArcSec Maximum Backlash* ±ArcSec Peak Torque at Output Nm Maximum Velocity Output RPM Maximum Acceleration rad/sec Input to Output Ratio (assuming 1:1 gearhead) 64:1 11:1 17:1 22:1 Gear/Pinion Ratio 6.4:1 11:1 17:1 22:1 Estimated Pinion & Ring Gear Life** 6 Million Contacts per Pinion Roller or 3 Million per Gear Tooth Output Inertia kgm Pinion Inertia kgm 2.25 Total reflected inertia to gearbox output kgm Maximum Bearing Drag Torque Nm * All performance specifications assume using Nexen s standard 1:1 high precision reducer. Other customer specified reducers can be requested but will have an impact on the above specifications. ** Life rating is an estimate based on maintaining published accuracy specifications while operating with allowable dynamic loading. Nexen does not guarantee life since it can be impacted by environmental conditions, and lubrication intervals. 21 Courtesy of Steven Engineering, Inc - (8) sales@steveneng.com -

22 INDUSTRIES & APPLICATIONS CUTTING SYSTEMS GANTRY SYSTEMS MEDICAL PRODUCTS ROBOTICS AEROSPACE MACHINE TOOL SEMICONDUCTOR MATERIAL HANDLING In accordance with Nexen s established policy of constant product improvement, the specifications contained in this document are subject to change without notice. Technical data listed in this document are based on the latest information available at the time of printing and are also subject to change without notice. For current information, please consult or contact Nexen s Technical Support Group at the location to the right. Nexen Group, Inc. 56 Oak Grove Parkway Vadnais Heights, MN (8) Fax: (651) Nexen has sales offices throughout the United States, Europe, Japan, and Australia. ISO 91 Certified 216 Nexen Group, Inc. FORM NO. L-21XXX-A Courtesy of Steven Engineering, Inc - (8) sales@steveneng.com -