Testing Services



STI provides a unique combination of traditional machine testing services and advanced analytical techniques. STI is a leader in providing machine testing and diagnostic services for turbomachinery, machine tools, cutting tools, turbine blades, mechanical systems, structures, rotating machinery and more. In addition, utilizing state-of-the-art equipment and customized software we diagnose the onset of mechanical vibration faults, performance degradation and component remaining life.














Vibration Testing, Analysis and Diagnosis

STI provides a number of services related to vibration measurement for both rotating and stationary components:
  • measurements of blade-disk vibrations
  • non-contacting blade tip vibration tests
  • shaft torsional vibration measurements
  • piping strain and vibration measurements.

IMI Sensors, a Division of PCB Piezotronics, Inc. offers a wide range of vibratory test and measurement solutions for rugged and demanding industrial applications.



Modal Testing Capabilities

  • Natural frequencies, mode shapes and operational deflection shapes(ODS) of rotating and stationary components
  • On-site testing
  • Generation of key verification data for FE computer models used in the failure analysis.
  • measurements of blade-disk vibrations
  • Experience on more than 300 different structures.
Download the technical paper, "The Relationship Between Finite Element Analysis and Modal Analysis" (pdf format)



Quality Control Blade Frequency Testing

"Refurbished or reverse-engineered turbine blades are frequency-tested to ensure compliance with original equipment specifications. This is especially critical for longer tuned blades that are susceptible to high-cycle fatigue failure due to operating resonances. STI Technologies has conducted quality control frequency testing of blades for over 20 years.

Download the Machine Testing and Diagnostics Services Brochure (pdf format)

Back To Top



Moment Weigh

STI provides moment weigh and the loading sequence for turbine blades. Data is collected (blade weight and center of gravity information) and used in a special software subroutine that will determine the exact blade stacking position (loading chart).

Back To Top



Strain Gage Testing - Stationary and Rotating

Telemetry Capabilities

  • Verify analytical models
  • Establish safe operating loads
  • Applicable to high temperatures and aggressive environments

Telemetry services include:

  • Selection of gage size and type, number of gages.
  • Recommended bonding methods, and gage orientation.
  • Considerations of temperature, test duration and required accuracy.
  • Practical strategies for dealing with lead wire paths, connection terminals, clearances and gage protection.

Download the Machine Testing and Diagnostics Services Brochure

Back To Top



Custom Measurement Instruments (Transducers)

In partnership with the PCB Group, STI Technologies Inc. can provide customized measurement instruments to meet specific needs. Applications range from smart sensors and wireless transducers, special mounting or installation requirements, data acquisition systems and customized software applications to process the data.

Back To Top



Pressure, Force, Torque and Acoustic Measurements

STI Technologies Inc. is uniquely positioned, through its relationship with the PCB Group of companies, to offer a range of pressure, force, torque and acoustic measurement services and a full range of data analysis tools for evaluation and resolution, as well as access to a host of pressure, force, torque and acoustic sensing devices.

PCB Piezotronics, Inc.

PCB, Pressure and Force Sensors

Key Transducers, Inc.

Larson Davis

Back To Top



Data Acquisition and Reduction

STI offers custom virtual instrument design with LABVIEW software and National Instruments data aquisition cards. Calibration systems include shock accelerometer calibration based on Hopkinson bar, transverse sensitivity, calibration of accelerometers at various temperatures (includes environmental chamber temperature control, shaker motion control, data acquisition and processing) as well as data aquisition and processing systems for turbomachinery and general vibration applications. Experience indicates that virtual instruments provide significant cost reduction through flexibility.

Download the Machine Testing and Diagnostics Services Brochure.

Back To Top



Equipment Rental

STI and our affiliates have a large selection of test equipment available for rent. A partial listing includes:

  • Accelerometers
  • Acoustic transducers
  • Array microphones
  • Cables, accessories and adaptors
  • Variety of data acquisition and analysis equipment
  • Dosimetry
  • Environmental systems
  • Force sensors
  • Handheld accelerometer calibrators
  • Impact Hammers
  • Microphone power supplies/preamplifiers
  • Signal conditioning
  • Sonic Digitizers
  • Sound Level meters
  • Tachometers

Download the Machine Testing and Diagnostics Services Brochure

Back To Top



Flow Path Traverse Testing

Field tests can be performed within the flow path of operating steam turbines to measure span-wise distributions of pressure, velocity, and flow angles. These tests, performed using pitot-static probes and developed under the sponsorship of EPRI, help diagnose steam path design problems and produce flow conditions for subsequent CFD stage models.

Back To Top



Steam Wetness Measurements

A custom optical probe is used to characterize the quantity of condensed steam in two-phase flow near the turbine exhaust. The wetness probe is traversed to yield span-wise distributions of wetness. Both test equipment and procedures were developed under the sponsorship of EPRI.

Back To Top