Mitutoyo Offers Portable Surface Roughness Measuring Instrument

The SJ-220 portable surface roughness measuring instrument has touchscreen and wireless capabilities. The intuitive touchscreen has a user interface that supports fingertip operations, including flick and swipe gestures that allow the user to change display screens and adjust settings. The touchscreen can be disabled, too, offering flexibility in different work conditions.

The device’s larger 2.8-in. screen with high visibility and backlighting allows for use in dimly lit environments. Users can switch the screen orientation between vertical and horizontal to suit their preference. Complementing the touchscreen are physical buttons, including a new Home key, to ensure accessibility even when users wear gloves and cannot use the touch interface. The Home key provides quick access to the home screen, daily menu, calibration settings and measurement conditions.

Portability is improved with a built-in battery that supports approximately 1,000 measurements on a full charge, for operation in environments without external power. In tandem with the U-WAVE-TIB wireless data transmitter the SJ-220 facilitates cableless and paperless workflows by transmitting measurement data wirelessly.

The lightweight, compact device is designed to accommodate a range of manufacturing needs and allows users to measure surface roughness directly on-site.

Machine Design had some follow-up questions about Mitutoyo’s latest addition to its SJ-200 series, so we reached out to Chris Lee, form products manager at Mitutoyo America Corporation.

Editor’s note: Questions and answers may be edited for clarity and style.

Machine Design: How does the accuracy and repeatability of the SJ-220 compare to previous models in the SJ-200 series, and what impact can this have on quality control and manufacturing?

Chris Lee: The accuracy and repeatability of the SJ-220 is the same as the previous SJ-210 model. The mechanics, detectors and drive units are the same so both generations can support it.

MD: Can you explain how the wireless data transmission via the U-WAVE-TIB improves workflow efficiency on the production floor, especially for larger complex workpieces?

CL: Wireless data transmission allows for sending important measurement data longer distances. The absence of a cable for data transmission also allows the unit to take measurements in hard-to-access areas that would be too difficult or not possible if a wire was connected to the instrument. The SJ-220 can connect to Android phones with the free SJ-App for operators to review measured results remotely in real-time or to send the data to SPC reporting software such as MeasurLink.

MD: What specific surface roughness parameters can the SJ-220 measure, and how do these measurements aid design engineers and product development and material selection?

CL: A majority of the industry utilize and need only the Ra parameter; however, the SJ-220 now supports parts of the new ISO 21920 texture standard to provide greater consistency, traceability and compliance for industries requiring the highest levels of quality controls.

MD: How does the SJ-220’s built-in battery performance and portability influence maintenance schedules and on-site inspection protocols in industrial environments?

CL: The portability of the SJ-220 is the instrument’s biggest advantage. Its slim drive unit and rectangular design fits in areas where other brands can’t while still being easy to use with one hand. The SJ-220’s large screen display is backlit for clear readings in dim areas, and the screen’s glass allows for operation while wearing inspection gloves. With a full charge, the battery lasts for about 1,000 individual measurement cycles and takes about four hours to fully charge once the battery is drained.

MD: How does the device handle measurements on curved or irregular surfaces, and what best practices should engineers follow to ensure accurate data collection in these cases?

CL: The SJ-220 series is designed only for measuring on flat surfaces, and it’s not recommended for analyzing curved or inclined areas. However, it can measure along an axial axis on a curved part using a nosepiece to keep the instrument aligned. It also has the “transverse” drive unit type for measuring along the axial axis using alignment tools such as adapters.