自動動態抗開裂測試儀是涂層檢測儀器,適用于測試以水泥、聚合物粉末、合成樹脂乳液或其它材料為主要粘結劑,配以填料、助劑等組成的外墻找平膩子開裂性測試。自動動態抗開裂測試儀依據JG/T157-2004行標設計制造。
自動動態抗開裂測試儀工作原理:
★由于建筑物的不均勻的干濕變化、熱脹冷縮、結構沉降及設計、施工上的不完整等原因,幾乎所有建筑都不同程度地存在表面毛細裂縫、表面貫通裂縫、結構性裂縫。
★外墻裂縫不僅大大降低了對建筑物外墻的保護作用,也給涂飾面的美觀造成了一定的影響。為了彌補上述之缺陷,在涂刷外墻乳膠漆之前,必先在墻體涂刮一層外墻膩子;而外墻膩子的質量優劣,則是關鍵之關鍵。
★測試儀依據JG/T157-2004行標設計制造的QDK型自動動態抗開裂測試儀適用于測試以水泥、聚合物粉末、合成樹脂乳液或其它材料為主要粘結劑,配以填料、助劑等組成的外墻找平膩子。
★電機通過齒輪減速后拖動頂桿作上升運動,刃口產生上頂力,使石綿水泥板在規定的區域內逐步產生細微裂紋并控制裂紋緩慢擴展,觀察膩子層的開裂情況,以此表征膩子抵抗基材裂紋擴展的能力。
主要技術指標:
★刃口長:150mm
★刃口夾角:30度
★大升程:20mm
★上升速率:3mm/min
★型框規格:200×150×2(mm)
★外形尺寸:200X150X2mm
★重量:75kg
Main technical indicators of QDK automatic dynamic crack resistance tester
★ Blade length: 150mm
★ Blade angle: 30 degrees
★ Large lift: 20mm
★ Rising rate: 3mm / min
★ Frame specifications: 200 × 150 × 2 (mm)
★ Dimensions: 200X150X2mm
★ Weight: 75kg
使用試驗方法:
★將型框放在200×150(mm)的石綿水泥板上。在將配制好的膩子涂刮在型框內。
★將型框取下,涂刮好的石綿水泥板應在標準環境下養護7d。每一樣品應同時制備3塊試板。
★將養護好的試板卡固在本儀器的工作臺面上。啟動電源開關后在啟動上升開關,此時刃口緩慢上升。
★刃口繼續緩慢上升。此時應注意觀察石綿板的空白區域,當發現裂紋出現后,使用立式讀數顯微鏡觀察并隨時記錄裂紋寬度,至膩子層開裂前為止。啟動停止開關后,刃口不再上升。
★記錄膩子層開裂前,石綿水泥板裂縫的A大寬度。 到0.02 mm。
★啟動下降開關,使刃口退回原位。
★松開試板卡固螺母及壓板,取下試板。在放入另一塊試板,重復上述試驗步驟。
QDK automatic dynamic crack resistance tester using test method
★ Place the frame on an asbestos-cement board of 200 × 150 (mm). Squeeze the putty into the frame.
★ Remove the frame. The asbestos-cement board coated should be cured under standard environment for 7 days. Three test plates should be prepared for each sample.
★ Fix the cured test plate on the work surface of the instrument. After the power switch is turned on, the rising switch is started, and the cutting edge rises slowly at this time.
★ The edge continues to rise slowly. At this time, pay attention to the blank area of the asbestos board. When cracks are found, use a vertical reading microscope to observe and record the crack width at any time until the putty layer cracks. After activating the stop switch, the cutting edge no longer rises.
★ Record the large A width of the crack in the asbestos cement board before the putty layer cracks. to 0.02 mm.
★ Activate the lowering switch to return the cutting edge to its original position.
★ Loosen the retaining nut and pressure plate of the test plate and remove the test plate. After placing another test plate, repeat the above test steps.
結果判斷:
三塊試板中以數值較近的每塊試板的測試結果的算術平均值作為A終結果。
Judgment of QDK Automatic Dynamic Crack Resistance Tester
Among the three test plates, the arithmetic average of the test results of each test plate with the nearest value is taken as the final A result.