In part 1, we reviewed how Magnetostrictive Linear Position Sensors are a common type of position sensor for hydraulic cylinders where high resolution is a concern.  Magnetostrictive sensors can consume a fair amount of power and are not the most mechanically rugged sensor technology.  A drawback of the solution with heavy duty hydraulic application is the sensitivity of the hollow waveguide tube to hot temperatures, shock and vibration.

Magnetostrictive Sensor Field Replacement for Immobile Hydraulics

Plant managers operating scale manufacturing may have dozens of hydraulic systems using position sensors. The larger the stroke length, the more susceptible the long waveguide is to sagging due to high heat and gravity. A plant manager then has to maintain stock in each and every stroke length of sensor to insure quick replacement when necessary. The CPI SL series sensor is the go-to replacement, as it is a form-fit-function replacement for a magnetostrictive sensor in almost any stationary cylinder in all stroke lengths.

A Superior Magnetostrictive Sensor Replacement

The CPI SL series picks up where traditional magnetostrictive sensors leave off.  The sensor technology is completely non-contacting, and is a drop-in replacement for existing magnetostrictive sensors in long stroke applications. No core drilling of the piston rod is required at all because the sensor can be screwed into the bore left behind by the broken magnetostrictive sensor Once CPI SL series position sensor can cover stroke lengths from 10” to 10 meters.

1. The sensor is fully qualified in the field to operate in this application for over 1 million cycles.
2. The sensor fits easily into the bore used for the magnetostrictive sensor, no core drilling of the piston rod is required.
3. The sensor can provide either analog voltage in 5 different ranges, or analog current output in the standard 4 to 20ma range.
4. The sensor provides absolute position with pushbutton auto-calibration for ease of endpoint scaling.
5. The sensor has a greatly improved temperature range up to 300F. Magnetostrictive sensors are typically rated to 170F max.

About CPI

CPI is a US based manufacturer of LVDT based linear position sensors. Heavy duty materials and robust performance characterize all of CPI’s products. Industries served include Oil & Gas, Naval and Boat Industries, Heavy Industry, Mining equipment, Safety, Production Equipment, Construction Vehicle manufacturers and many more.

Visit our website today to learn more: www.cpi-nj.com

 

The main measurement technology for portable hydraulic cylinders takes advantage of the Magnetostrictive characteristics of ferromagnetic metals. Magnetostrictive sensors are complicated, and use the Villari and Wiedemann effects generate an ultrasonic surge that travels at the speed of sound through a cylindrical waveguide.

Fig 1. – The Physics of Magnetostrictive Position Sensors

 

Magnetostrictive Sensors & Mobile Hydraulics

The issue with Magnetostrictive Sensors is that while they are highly accurate, they are an extremely vulnerable position sensing technology for applications such as Construction, Mining Equipment, and Drilling. Their high resolution and vulnerability increases both the costs and intricacy of servicing in the field.

Drop-In Magnetostrictive Position Sensor

We get it: You’ve used magnetostrictive sensors for years; you know them and when they break you know how to replace them. But what if there was an alternative cost neutral technology to provide tough position measurement in the field? That’s right we are talking about a field proven drop-in replacement for most sensors.

In our next blog, we will cover how CPI engineered an advanced solution to linear position measurement in mobile hydraulics, and why it’s time to try something new.

Visit our website to learn more at: http://www.cpi-nj.com/.