EN
ar
bg
hr
cs
da
nl
fi
fr
de
el
hi
it
ko
no
pl
pt
ro
ru
es
sv
tl
iw
id
lv
lt
sr
sk
sl
uk
vi
et
hu
th
tr
fa
ms
hy
ka
ur
bn
mn
ta
kk
uz
ku
crack gauge
Kingmach crack gauge include the JMDL-21XXAT Smart General-Purpose Displacement Meter, a compact instrument for relative displacement and expansion joint movement. The product is used in buildings, railways, transportation works, hydropower structures, dams, and bridge projects where two structural components may move against one another. Listed ranges include 50 mm and 100 mm, with 0.01 mm resolution and 0.5%FS accuracy. The meter is based on inductive frequency modulation, which supports high sensitivity, stable long-term observation, and low temperature influence. A built-in memory chip stores sensor model, serial number, calibration coefficient, time, temperature data for temperature versions, absolute displacement, relative displacement, and zero-point value. It can save 800 measurement results, which is useful when checking site history after construction stages or weather events. When connected to an integrated tester or automatic acquisition system, readings can be reviewed quickly without relying on manual gauge notes. During project setup, the measuring point should be matched with the expected travel direction, available mounting space, cable route, and required acquisition interval. This prevents a short-range joint instrument from being used on a long-travel point, or an exposed sensor from being placed where an embedded anchor is needed. It also helps the monitoring team set a baseline that can be defended during acceptance and later maintenance review.
Application of crack gauge
In railway and highway subgrade monitoring, crack gauge are used to observe geogrid deformation, embankment movement, track foundation displacement, culvert joint movement, and settlement-related structural shifts. The field problem is that deformation may occur inside reinforced soil or pile-net foundations where visual inspection cannot reach after backfilling. Kingmach JMDL-24XXAT flexible displacement meters are designed for geogrid materials in reinforced soil and pile-net subgrade foundations. The bendable measuring rod can deform with the geogrid, while both ends are clamped using mounting brackets. Listed ranges are 30 mm and 50 mm, with 0.01 mm sensitivity, 0.5%FS accuracy, 20-point curve fitting, and a designed service life up to 30 years. For larger movement, JMLS-22XXADT wire rope sensors and JMDL-49XXAT formwork or steel wire meters can support long-distance displacement monitoring. These readings help maintenance teams connect settlement, traffic load, rainfall, and construction records. During operation, the monitoring team should keep the baseline, temperature, inspection notes, and nearby sensor behavior in the same review file. This makes it easier to tell whether a movement trend comes from normal service, a repair event, changing load, water influence, or developing structural risk. Clear records also help owners decide when a field inspection is needed instead of waiting for visible damage.
The future of crack gauge
Future crack gauge will also become easier to install in cramped and irregular field locations. Many monitoring points are not clean laboratory setups; they are narrow tunnel headings, wet dam galleries, crowded bridge joints, temporary formwork frames, steep slopes, and machinery spaces with limited room for tools. Smaller housings, clearer mounting accessories, stronger cable exits, and simpler alignment checks will reduce installation errors. Kingmach already uses several physical formats, including crack gauges with measuring rods and bases, draw-wire sensors for longer travel, embedded bedrock assemblies, flexible geogrid meters, and non-contact magnetostrictive meters. Future product development can make these formats more modular, so engineers select the mounting kit, cable protection, connector type, and acquisition method together. That would shorten commissioning time and make later maintenance less dependent on the original installer. For projects with many measurement points, practical installation improvements can be as important as another decimal place of resolution, because a well-mounted sensor gives cleaner data from the beginning.
Care & Maintenance of crack gauge
For flexible geogrid crack gauge, installation care is more important than later access because the product may be buried inside reinforced soil. Kingmach JMDL-24XXAT uses a bendable measuring rod, 30 mm and 50 mm ranges, 0.01 mm sensitivity, 0.5%FS accuracy, 20-point curve fitting, and a designed service life up to 30 years. Both ends of the geogrid should be clamped with the flexible sensor sections using mounting brackets so deformation transfers reliably. Avoid sharp bending, cable tension, bracket slippage, and damage during filling or compaction. Record the geogrid layer, chainage, depth, sensor direction, zero value, and backfill date. During operation, compare displacement with settlement and rainfall records. If the trend changes after heavy rain, traffic loading, or nearby excavation, inspect accessible cabinets and cables before deciding whether the buried geogrid movement itself has changed. Keep the installation photo, point number, zero value, and expected movement direction with the commissioning record for later review. If a reading changes after maintenance work, inspect the base, anchor, cable, and cabinet before assuming the structure itself has moved.
Kingmach crack gauge
In structural monitoring, crack gauge should not be treated as single-purpose accessories. Kingmach displacement products can work with comprehensive testers, automatic acquisition systems, bus modules, RS485 output, and monitoring software, which allows movement data to sit beside strain, load, settlement, tilt, vibration, temperature, and water level. That combined view is important because displacement often has several causes. A tunnel crown reading may respond to excavation sequence, groundwater, lining age, or nearby traffic. A bridge joint may move with both temperature and bearing behavior. A slope reading may change after rainfall, blasting, or retaining wall loading. By using smart products with stored parameters and digital transmission, project teams reduce channel mix-ups and make later data review cleaner. The result is a monitoring chain where field installation, sensor identity, baseline readings, and platform curves can be checked against one another. The point should be named on the drawing, linked with its cable route, and checked against the expected movement direction before the first automatic reading is accepted. For daily review, the reading should be compared with nearby points, recent weather, site operations, and any loading event that could explain the movement.
FAQ
Q: What are crack gauge used for?
A: They measure movement such as relative displacement, crack width, expansion joint travel, bedrock deformation, rock layer movement, geogrid deformation, formwork settlement, and equipment stroke.
Q: Which Kingmach models belong to this category?
A: Common models include JMDL-21XXAT, JMDL-22XXAT, JMDL-24XXAT, JMDL-31XXAT, JMDL-32XXAT, JMDL-49XXAT, JMDL-52XXADT, JMCW-21XXADT, and JMLS-22XXADT.
Q: What range should be selected first?
A: Start from the expected movement. Short joint monitoring may need 20 mm to 100 mm, while draw-wire or equipment travel may require 500 mm to 2000 mm.
Q: Can these products support remote monitoring?
A: Yes. Several Kingmach models support digital transmission, RS485 communication, automatic acquisition, integrated testers, or unattended monitoring systems.
Q: Why is the baseline reading important?
A: All later movement is compared against the starting point. The baseline should be recorded after the sensor, bracket, anchor, cable, and structure are stable.
Reviews
Daniel Brown
Excellent environmental monitoring sensors. The data is consistent, and the system integrates smoothly with our existing setup.
Robert Taylor
The weir flow meter is well-built and delivers accurate measurements. Great value for water management applications.
Latest Inquiries
To protect the privacy of our buyers, only public service email domains like Gmail, Yahoo, and MSN will be displayed. Additionally, only a limited portion of the inquiry content will be shown.
Charlotte***@gmail.comUnited Arab Emirates
Hi, we require instrumentation cables suitable for harsh environments. Could you advise on specifica...
Isabella***@gmail.comGermany
Hello, we are evaluating weir flow meters for a water management project. Please share accuracy deta...
Related product categories
- Differential Displacement Meter
- Smart Crack Gauge
- Wire Rope Displacement Sensor
- GPS Displacement Monitoring System
- displacement meter
- laser displacement meter
- Flexible Displacement Meter
- Multi-point Displacement Meter
- Single-point Displacement Meter
- Smart General-Purpose Displacement Meter
- Smart Flexible Displacement Meter
- Magnetostrictive Displacement Meter