Roof Tell-Tale Extensometer

Measuring How Far the Roof Splits

The Roof Delamination Detector measures separation displacement in the roof of bolt- and cable-supported roadways, giving engineers data on whether bolt and cable lengths are adequate and how well anchorage is working. It carries two anchor heads, one set in shallow strata and one in deep strata; when the roof deforms, the displacement difference between the two heads shows on a graduated scale.

The measuring wire is stainless steel, so it does not rust and seize in the wet underground air, and the scale numbers are spray-printed, waterproof, and will not peel off as sticker scales do. The scale uses red, yellow, and green zones: small delamination in green means safe, middle in yellow means watch, large in red means act. The anchor heads grip firmly in the drill hole without slipping, so the displacement reading stays accurate.

The detector uses two monitoring points, with a shallow-base range of 150 mm and deep-base range of 200 mm at plus or minus 1 mm accuracy; monitoring depth runs 3 m shallow and 8 m deep, with measurement depths adjustable from 2 to 10 m.

MOQ is one unit. It is a standard instrument in roadway roof-monitoring programs. The anchor heads grip firmly in the drill hole without slipping, so the displacement reading stays accurate rather than drifting. The color zones let a worker judge status at a glance without reading exact numbers, which speeds the daily roof walk. Monitoring depth runs 3 m at the shallow anchor and 8 m at the deep anchor, with measurement depths adjustable from 2 to 10 m, at plus or minus 1 mm accuracy. The two anchor heads report the displacement difference on the painted scale. Stainless wire and printed markings avoid the rust and peeling that shorten the life of cheaper plastic-scale units.

Hot Tags: roof tell-tale extensometer, China roof tell-tale extensometer manufacturers, suppliers, factory