Device name：Upgraded Horizontal Shrinkage Expansion Instrument
Model：YC-HSP540D
Origin：Peking
Purpose：A special instrument for measuring the change of length (volume) of concrete specimens during hardening under certain environmental conditions.

現(xiàn)有限制膨脹率測(cè)定儀存在如下不足：
（1）標(biāo)準(zhǔn)中校準(zhǔn)桿材質(zhì)建議選擇硬鋼或石英玻璃材質(zhì)制作，但目前市場(chǎng)上的校準(zhǔn)桿基本上都為不銹鋼材質(zhì)，不銹鋼校準(zhǔn)桿的線膨脹系數(shù)很大，易因溫度波動(dòng)影響造成誤差。
（2）千分表精度差，即使選用業(yè)內(nèi)較好的電子千分表也有±3um的測(cè)量誤差，一般的千分表誤差在±5um以上，這對(duì)于混凝土試件后期收縮量本來(lái)就很小而言，會(huì)造成很大的誤差。
（3）試驗(yàn)過(guò)程人工讀數(shù)記錄，易因人為筆誤或在數(shù)據(jù)抄寫(xiě)過(guò)程中失誤造成錯(cuò)誤。
并且，由于在整個(gè)試驗(yàn)周期中，同一個(gè)試件要測(cè)量十幾次，上述3種誤差因素會(huì)被不斷放大，很有可能出現(xiàn)前后試驗(yàn)結(jié)果相互矛盾的現(xiàn)象，且無(wú)法找到問(wèn)題根源。 

The shortcomings of available horizontal concrete shrinkage expansion meter:

(1) Hard steel or quartz glass is recommended for the calibration rod material in the standard, but the available calibration rod in the market is mostly made of stainless steel. Its linear expansion coefficient is too high, which is easy to cause errors due to the influence of temperature fluctuation.

(2) The accuracy of the micrometer is poor, even if the best electronic micrometer is used, because its measurement error is more than 3um. Generally, the error of the micrometer is more than 5um, which will cause a great error for the shrinkage of concrete specimens in the later period.

(3) Manual reading records during the test process are prone to errors, which is caused by human errors or errors in data transcription.

Moreover, the same specimen needs to be measured more than a dozen times in the whole test cycle. The above error factors will be enlarged continuously, and it is likely that there will be conflicting phenomena between early and later results. We can’t find the root cause of the problem.

Features:

1. More accurate: With the help of high-precision displacement sensor and invar calibration rod, the measurement error is less than 1um, which ensures the accuracy and comparability of long-term test results.

2. No needs for long-term on-line observation. Testing at the age can improve the efficiency of the equipment.

3. There is no need to record manually during the test process. All the data are stored in the test host. All results could be derived by the user through U disk, and then can be viewed by Excel.

4. The test results are marked by operators, and the test time, temperature and humidity of the test environment, specimen number, age and length are recorded at the same time.

5. The device has the function of permission setting, and the non-operator can’t log in, which ensures the safety of the test results.

Parameters：

Model:  YC-HSP540D

Measurement range of tester: 538-542mm

Measurement range of sensor:0-2mm

Error in measurement: ≤1um

Resolution：0.1um

Invar calibration cod: 540±0.1mm

Error of temperature sensor：≤0.5℃

Measurement range of temperature sensor：0-50℃

Error of humidity sensor: ≤3%RH

Measurement range of humidity sensor: 0-99%RH

Specimen size: 100×100×515mm

Host size: 370×340×240mm

Dilatometer bench size: 670×240×180mm

Power supply：AC220V/AC 110V