Abstract: The goal of this project was to evaluate the final assem-bly and testing operations for the 700/800 Series gear re-ducers produced by Lightnin SPX of Rochester, NY. The project operated within constraints of time, space, and budget. Process inefficiencies were identified and solved, which specifically required the redesign and relo-cation of the company’s torque test stand. The test stand was redesigned to minimize its footprint and height, as well as the setup and process time involved in its opera-tion.

Team Members (Left to Right)

Aditya Sanghi, IE Oriana Starr, ME

Donald Strong, ME Jesse Warner, EE

Ronald Mendolera, EE Dana Harris, IE

Geoffrey Cusano, ME

Due to the eight different input shaft heights, it is required that the eleva-tion of the input motor assembly be ad-justable so that the motor’s output shaft can be precisely coupled with the test unit’s input shaft. It is also desired that the test operator not make these height adjustments manually because of the op-erator’s inability to line up the two shafts with enough precision by eye. In order to make the necessary alignment with great precision, a position sensor will be used in a feedback loop along with a PLC to control the elevation of the input motor assembly. The position sensor is an MTS Temposonics ER-series with 500mm stroke and (20mV/mm) transfer function as shown in Figure above.

Couplings: The input couplings are designed to be quickly inter-changeable and easy to align. The couplings are de-signed to be slid over the end of the universal male keyed coupling. There are two keyseats cut into one end of the couplings in order to make alignment with the input of the reducer easier and more efficient. In order to make the couplings as lightweight as possi-ble the universal end of the female coupling, which mates with the universal male, was designed with the smallest diameter and length as was prudent. The output couplings were designed with the express purpose of reducing the required setup time of the torque stand. Female splines were used to replace the current method of bolting the couplings to the slave. Male splines are cut into the end of each cou-pling and a permanent female is attached to the slave. This allows for the slave to be attached to the cou-pling without any adjustment of the couplings them-selves because the output coupling for each series is correctly sized for the necessary spline engagement. Stress analyses on the all couplings were done using the energy distortion method. A recommended 75% of the shear strength (for shafts with keyseats) was taken as the allowable stress on the shaft.

One of the final objectives of the electrical engineers was to simplify the data for each reducer tested into a more simplistic form. In order to keep accessible records of the reduc-ers that are tested, an interactive pro-gram was written using Visual Basic. The program was constructed ac-cordingly to the specification sheets provided to the RIT design team by SPX. (See Screen Shot Above)

In order to eliminate the time wasted running the test unit until the lube and brake transmission oils warm up, the oils will be stored in two separate heated, jacketed tanks that can bring the oils up to about 120 degrees before the unit is placed on the stand for testing. These tanks will not need to be heated all of the time, just for an adequate amount of time before a reducer is going to be tested. The lube oil requires an 80 gallon tank and the brake transmis-sion oil requires a 50 gallon tank. (See Above)

Final Torque Test Stand Design

The amount of torque applied to the input shaft of the test reducer will be automati-cally controlled through the use of a torque sensor, an electronic air pressure regulator, and a PLC unit with a user in-terface. The amount of torque is deter-mined by the amount of brake pressure experienced at the output of the slave unit. The brake is pneumatically-controlled with its pressure determined by an air pressure regulator. The test opera-tor will use the PLC interface to input the amount of torque desired based on which model gear reducer is being tested. The torque sensor will send its signal to the PLC where it will be compared with the desired torque entered by the test opera-tor. The PLC will then send the voltage output to the electronic air pressure regu-lator to adjust the brake pressure for either more or less torque.

Elevation Position Sensor Smart-Pak PLC - Entertron

ANSYS Simulation of the 782/882 Female Input Coupling

ANSYS Simulation of the 782 Output Coupling

Lightnin SPX 700/800 series mixers and gear reducers are heavy duty pieces of equipment designed to provide reliable service in large and de-manding applications. These applications range from pharmaceutical fer-mentation and large-scale chemical processing to minerals processing and heavy sludge waste treatment. The product is sold with a heavy-duty motor and mount. It is built in the facility with various configurations and sizes. They include the 780, 781, 782 and 783 series mixers and gear reducers. The output ranges from 25 to 1250 horsepower with output speeds of 11.4 to 230 rpm. The unit has an input shaft perpendicular to the output shaft. The styles and locations of the shafts are model dependent. These shafts reduce the speed at the output of the mixer while increasing the out-put torque.

3-D Rendering of the 782/882 Female Input Coupling

ANSYS Simulation of the 882 Output Coupling

3-D Rendering of the 782 Output Coupling

3-D Rendering of the Female Spline

3-D Rendering of the 882 Output Coupling

ANSYS Analysis Simulation of the Female Spline

Finite Element Analysis Cosmo Simulation (Left) 3-D Rendering of the Final Torque Test Stand (Right)

Heated Oil Tank

39524236135Spin & Torque

29524136135Torque

168713031Spin

10226760Assembly

TotalWalk During/

Transport to NextValue AddedSetup

39524236135Spin & Torque

29524136135Torque

168713031Spin

10226760Assembly

TotalWalk During/

Transport to NextValue AddedSetup

Time study data: 782/783 Size

99.427.58107

59.500.50During setup60After setupOil

20.670.33Spline21Flanged couplesCouple

11.756.25Rail & couple10Flanged input shaftDistance

7.500.50Adjustable lift16Spacer platesHeight

Time Saved (min)

Times (min)

New Equipment

Times (min)

Old EquipmentTask

99.427.58107

59.500.50During setup60After setupOil

20.670.33Spline21Flanged couplesCouple

11.756.25Rail & couple10Flanged input shaftDistance

7.500.50Adjustable lift16Spacer platesHeight

Time Saved (min)

Times (min)

New Equipment

Times (min)

Old EquipmentTask

Estimated time saved over 1.5