熱浸程序
所有鋼化玻璃板均須經熱浸程序處理。“熱浸"程序,有效降低硫化鎳損害的風險的熱浸程序,通常包括一個處理玻璃板的烘爐,過程 分三個階段進行。加熱階段開始時,先將所有玻璃板置於周圍環境溫度中,當最 後一塊玻璃板表面溫度升至攝氏 280 度時,此階段便告完成。當所有玻璃板的表 面溫度達到攝氏 280 度時,保持階段便開始。保持階段最少要持續 2 小時。在保 持階段進行期間,玻璃板表面溫度應保持在攝氏 290 度 ±10 度。當最後一塊達到攝 氏 280 度的玻璃板完成了保持階段,冷卻階段便開始。當烘爐內的氣溫降至攝氏 70 度時,冷卻階段便會告終。廣泛地被認可為能加速排除鋼化玻璃 中 的 硫 化 鎳 包 含 物,而 且 是消除鋼化玻璃中的硫化鎳的最有效 方 法。因 此,所 有 鋼 化 玻 璃板須遵照 BS EN 14179-1:2005 或其他相等的國際標準進行 熱 浸 程 序,以 作 為 適 用 於 幕 牆、玻 璃 窗 及 玻 璃 牆 工 程 的 鋼 化 玻 璃的品質控制措施之一。
Heat Soak Process
All tempered glass panes should be heat soak treated. It is widely recognized that heat soak process that significantly reduces the risk of damaging nickel sulphide usually includes, inter alia, an oven of taking the glass panes through three phases of the process. The heating phase commences with all the glass panes at ambient temperature and concludes when the surface temperature of the last glass pane reaches 280°C. The holding phase commences when the surface temperature of all the glass panes has reached a temperature of 280°C. The duration of the holding phase is 2 hours minimum. The surface temperature of the glass panes shall be maintained in the range of 290°C±10°C during the holding phase. The cooling phase commences when the last glass pane to reach 280°C has completed its holding phase. The cooling phase can be concluded when the air temperature in the oven reaches 70°C which accelerates the expulsion of the nickel sulphide inclusions in tempered glass and that heat soak process is the most effective means of eliminating tempered glass with nickel sulphide. It is therefore required that heat soak process conforming to BS EN 14179-1:2005 or other equivalent international standards should be carried out to all tempered glass panes, as one of the quality control measures for tempered glass used in curtain wall, window and window wall works.
熱浸程序的符合規定報告
根據《建築物(管理)規例》第10條,在批准圖則時會施加規定,要求有關人士在申請佔用許可證前,須呈交由玻璃生產商發出並由註冊結構工程師批註的熱浸程序的符合規 定報告。熱浸程序的符合規定 報告須包括以下資料:
(a) 鋼化玻璃生產商的名稱;
(b) 使用有關生產商的鋼化玻璃的項目名稱;
(c) 項目中使用的鋼化玻璃 板的總數和總表面面積;
(d) 為 (c) 項的玻璃板進行熱浸程序 的烘爐的所在位置 和識別編號;
(e) 按 照 BS EN14179-1:2005 或其他相等的標準所編 寫的烘爐校準報告3;
(f) 用以量度烘爐內玻璃表面溫度的熱電偶的數量和 8 排列方式。最少應使用 個熱電偶4。熱電偶的位 置須按烘爐校準報告而決定;
(g) 8 個熱電偶在熱浸程序的加熱階段、保 持 階 段 及 冷 卻階段的記錄溫度與時間關係圖表;
(h) 符 合 BS EN 14179-1:2005 或其他相等的國際標準 的 鋼 化 玻 璃 板 的 數 量、尺 寸 和 厚 度,以 及 每 次 進 行 熱浸程序時的玻璃板破碎記錄和相關的烘爐編 號;及
(i) 進行熱浸程序的日期
Compliance Reports for Heat Soak Process
Under Regulation 10 of the B(A)R, a requirement will be imposed, when giving approval of plans, to require the compliance reports for heat soak process issued by the glass manufacturers and endorsed by the RSE to be submitted prior to the application for occupation permit. The compliance report should contain the following information:
(a) Name of the tempered glass manufacturer;
(b) Name of the project using the manufacturer’s tempered glass;
(c) Total number and surface area of tempered glass panes used in the project;
(d) Location and identity number of the ovens, in which the heat soak process of the glass panes in (c) was conducted;
(e) Calibration report3 of the ovens in accordance with BS EN 14179-1:2005 or equivalent;
(f) Quantity and configuration of thermocouples used to measure the glass surface temperatures in the oven. A minimum of 8 thermocouples4 shall be used. The location of these thermocouples shall be determined from the calibration report of the oven;
(g) Recorded temperature versus time graphs for each of the 8 thermocouples during the heating phase, holding phase and cooling phase of the heat soak process;
(h) Quantity, dimensions and thickness of the tempered glass panes conforming to BS EN 14179-1:2005 or other equivalent international standards, and the record of breakages of panes in each heat soak process with corresponding oven number; and
(i) Date of carrying out the heat soak process.
科技日新月異。我們鼓勵認可人士和註冊結構工程師不時探討玻璃生產商日後可能提出的品質控制新方法,以避免錯失一些創新和合符經濟原則的品質控制方法。有見及此,如認可人士/註冊結構工程師提出熱浸程序以外的品質控制方法。
為確保進行熱浸程序時能準確達到正確溫度,應定期校準烘爐。通常,每年校準烘爐一次。
以熱電偶監察玻璃表面的最高和最低溫度。就荷載量為10%的烘爐而言,應在兩 個位置分別確立兩個最高溫的監察點,並在另外兩個位置分別確立兩個最低溫的 監察點。就荷載量為 100%的烘爐而言,同樣應在兩個位置分別確立兩個最高溫的 監察點,並在另外兩個位置分別確立兩個最低溫的監察點。因此,最少應使用 8 個熱電偶監察烘爐內玻璃表面的溫度。按香港實驗所認可計劃補充準則第 2 號 建 議,應每半年校準熱電偶一次。
不時審查玻璃製造商日後可能提出的新質量控制方法。在這方面,如果認可人士/註冊結構工程師提出了除熱浸工藝之外的任何質量控制法,便應就其建議方法呈交所有詳情,包括有關的原理、方法 說明和限制,以證明建議方法的適用程度。
Technology is constantly changing. In order not to preclude new quality control methods that are innovative and economical, APs and RSEs are encouraged to discuss new quality control methods that glass manufacturers may propose in the future. In view of this, if an APs and RSEs propose a quality control method other than the hot dip process
The oven should be calibrated at regular intervals in order to ensure the accuracy in achieving the correct temperature during heat soak process. Usually, the calibration period for oven is set at one-year interval.
Thermocouples are used to monitor the highest and lowest temperatures on the glass surfaces. For the 10% loaded oven, 2 locations for the 2 highest temperatures and 2 locations for the 2 lowest temperatures should be identified. For the 100% loaded oven, 2 locations for the 2 highest temperatures and 2 locations for the 2 lowest temperatures should similarly be identified. Hence, a minimum of 8 thermocouples should be used for monitoring glass surface temperatures in the oven. The thermocouples are calibrated at 6-month intervals as recommended in the HOKLAS Supplementary Criteria No. 2
review from time to time new quality control methods that may be proposed by the glass manufacturers in future. In this respect, if any quality control method other than heat soak process is proposed by the AP/RSE, full details of the proposed method including the principle, method statement and limitations should be submitted to demonstrate suitability of the proposed method.