VW Load Cells

VW Load CellsInstrument Details

Make : ACE Instruments Co Ltd, Korea
Model : VW Load Cell-1102
Specification :  
Rated Capacity : 30 ton
Accuracy : 0.5% FSR
Safe overload : 150% FSR
Sensor element : Vibrating wire sensor

A load cell is a transducer which converts force into a measurable electrical output. Although there are many varieties of load cells viz vibrating wire, strain gage, etc. Strain gauge load cells are the most commonly used type. Vibrating Wire Load Cells consist of a cylinder of high strength steel with 3 to 6 vibrating wire strain sensors (depending on capacity) mounted parallel to the longitudinal axis arranged equidistant around the circumference to measure the compression of the cylinder under load. They are manufactured with a centre hole to accommodate anchors, rock bolts and tendons. With the multi sensor configuration it is possible to obtain accurate readings under mildly eccentric loading conditions as the sensors are read individually. The readings from the individual sensors are averaged and when used in conjunction with a calibration factor, supplied with each cell, allow the applied load to be calculated.

Working Principles

Hollow type VW load cells are attached with VW strain gauge divided into 3-6 equal parts in the pipe hole of cylindrical shape cell that is processed mechanically with alloyed steel. It is used with the principle that when load operates in cell, tension of VW gauge changes. When load applied on the cell, change in tension of the gauges cause change in the frequency that is induced by a plucking coil. Vibrating wire strain gauges are essentially taut wires which change their natural resonant frequency in proportion to the square root of tension placed on them. In practice these elements are used in various sensors designed to measure soil pore pressure, strain in structure, rock stress, overburden pressure, etc. The average of the readings from the cells represents the mean load on the anchor, minimising the effects of eccentric loading.

Applications

The VW load cells are designed to measure loads in tiebacks, anchors, struts, rock bolts and strand structures.

  • Long term measurement of loads in tiebacks, struts, rock bolts and anchors.
  • Measurement of loads in supporting systems such as retaining walls, tie backs and anchors.

User Instructions

  1. Please use the bearing plate as per the capacity of plate.
  2. When setting up, please be careful lest apply eccentric load.
  3. When equipping to Earth anchor or rock bolt use strand cone of high quality of exactness.
  4. When contacting to readout unit, put to earth the shield wire.
  5. Before setting up, please be aware of instruction manual.

Contact Details

CSIR-Central Road Research Institute,
Delhi-Mathura Road, New Delhi-110025
Phone: +91-11-26848917 (Director), 26312412 (COA office), 26832173 (Reception)
Fax: +91-11-26845943
Email: director.crri@nic.in

Instrument Usage Charges(Including GST)

Inspection and Testing Charges: Rs./- per unit
The Demand Draft should be payable in favour of“The Director, CSIR-Central Road Research Institute, New Delhi”
Letter, DD & Samples send to “HOD-BES, CSIR-Central Road Research Institute, New Delhi