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FERRO PTCR測溫環工作原理及使用方法: |
1、FERRO PTCR測溫環具有可靠性,測溫環幾乎可被放置在窯爐的任何位置,爐體內、推板或傳輸帶上 ,在使用前,不必測量溫度; 2、FERRO PTCR陶瓷測溫環的工作原理是根據其在工作溫度范圍內的線性收縮,從而給出測溫環和燒成品的實際累計熱量,對照換算表得出測試溫度,燒制結束后,將測溫環取走并做記號; 3、FERRO PTCR陶瓷測溫環在窯爐中受熱時,它就收縮,并在*高溫度隨保溫時間延長而繼續收縮。 在其使用溫度范圍內,收縮率是線性的,這為FERRO陶瓷測溫環和被燒制的產品所受到的加熱量提供了一種實用的測量方法;收縮量(環直徑的減少)可用數字 千分尺測量 ,使用的手持數字千分尺記錄每一片測溫環的直徑, 到0.01mm; 4、參照包裝上所附的 環外徑與溫度對照表、溫度校正曲線圖(隨產品提供),所測出的測溫環直徑可轉換成 等效溫度。 注意:為了使用時和方便FERRO測溫環 每個溫度表都是為該批測溫環而特別制定的,所標的生產批號必須與溫度 對照表上的保持一致。 |
PTCR in practice: accuracy and convenience Firing process optimization In the process of establishing a standard, the firing process is characterized by 'mapping' the ring temperatures of PTCR rings distributed throughout the kiln. This allows the 'hot' and 'cold spots' to be detected and defined. Using the heat treatment mapping, the firing process can then be optimized by offsetting heat sources or thermocouples as indicated by the variations in ring temperatures. As a rule of thumb, one degree of ring temperaturecorresponds to one degree Celsius. The exact relationship between ring temperature and degrees Celsius is of course dependent upon the specific firing cycle of the kiln. The adjoining illustration shows two heat treatment mappings of the same 15m3 kiln. The first was generated before using thePTCR; the second, after firing process optimization using PTCR rings, resulting in substantial yield improvement. |
Firing process control In the course of time - as a result of aging of the heating elements or frequently alternating firing cycles - 'hot' and 'cold spots' maygradually return to the kiln.The PTCR can help here, too. once the firing process has been optimized, PTCR rings can be used regularly to monitor the firing process and to detect these deviations as they gradually arise, before they affect product quality. By comparing the current ring temperatures against the defined standard, the number of degrees of ring temperature by which the firing process must be adjusted can be determined. Using several rings at critical locations in the kiln ensures that an even heat distribution is maintained. Quality control at lower cost Besides the benefits of yield improvement through optimization of the firing process, the PTCR can also help reduce production costs.Simple comparison of ring temperature against a quality standard indicates whether the products are sintered to specification.Expensive, time-consuming conventional quality checks - destruction testing, geometry,density and porosity tests - can be reduced or eliminated. |
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測溫環測定窯爐溫度分布圖: |
測溫環被廣泛應用于連續窯和非連續隧道窯、梭式窯、輥道窯、鐘罩窯等等,推薦使用多位放置和多水平放置,這可使您對窯內熱分部有個直接地了解。 FERRO PTCR測溫環可應用在氧氣、氮氣、空氣、真空和還原等不同燒成氣氛中。 |
窯爐應用FERRO測溫環測量的優點: |
1、FERRO測溫環使用機動靈活,可簡易方便測定爐內三維空間溫度分布的任何角落。 2、FERRO測溫環安放位置貼近產品實際受熱狀態,測定燒制品 實際受熱情況。 3、FERRO測溫環一致性良好,可以保證產品燒成制度的良好重現性,從而提高成品的合格率。 4、使用FERRO測溫環可以減少甚至不再需要通過對燒成品的幾何形狀,密度和多孔性測量或破壞性試驗。 從而減少生產過程中的質量控制成本。 5、FERRO測溫環陶瓷測溫環為可靠的高精度產品,具有公認的性和可靠性,的溫差達1.5—3℃。 |
Method of use Positioning PTCR rings can be placed at almost any location in the kiln, on kiln furniture, trolleys or transports. The use of both multi-location and multi-level positioning is recommended, as this provides the most insight into the heat treatment distribution within the kiln. Measuring The contraction of the PTCR diameter reflects the actual heat treatment at the point where the ring was located in the kiln. The diameter is easily measured using a PTCR micrometer - only a single measurement is required (as shown). PTCR micrometers Numerical (N) and Digital(D) have an integral, ergonomically designed solid base with a ring positioning chuck, which ensures the ring is always correctly positioned in the micrometer. This design not only simplifies the measuring process, but also improves the repeatability and reproducibility of ring temperature measurement. Converting to ring temperature The measured ring diameter is converted to ring temperature using the conversion table enclosed in each packing unit. Each table is specific to the particular batch of rings, for accuracy and convenience.The ring temperature is a practical single number which is useful for comparison purposes - for instance to relate the recorded heat treatment to the firing process and defined standards - so that any required adjustments can be made. It does not necessarily reflect the actual kiln temperature; the PTCR acts as an accumulator, measuring the total heat treatment over time, rather than the maximum temperature attained. Establishing a standard ring temperature In order to make ring temperature comparisons between different firings, a standard ring temperature must be defined. This is done by including PTCR rings in a series of firings, and relating their ring temperatures to the quality of the products produced. The ring temperature which corresponds to products fired to the correct specifications can be used as the standard. |
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用測溫環改善窯爐燒成產品質量的案例: |
1、測溫環在電子陶瓷產品生產中的應用 |
不論是電子陶瓷用粉體還是電容器、電阻器、電感器之類的電子陶瓷元器件,對電性能的要求都較高。在配方和生產工藝相對固定的情況下,燒制品的累積熱效應是直接影響產品電性能的因素,而熱效應主要是燒成溫度、保溫時間和燒成氣氛的綜合體現。 不同的燒成溫度、保溫時間和燒成氣氛會燒結出不同性能的產品;同一批產品在相同的保溫時間,但放置在爐子的不同部位也可能燒出不同質量的產品。在實際生產中,難以從生產過程中直接判斷或選別出良品就投入下道工序的生產,這樣生產出來的產品不良率容易處于失控狀態。而現有各類窯爐的測溫點都相對固定,熱電偶的實際探測點的分布也受到限制,不利于掌握產品在燒成中的真實狀態。 另外,即使忽略不同材料的熱電偶和新舊不同的熱電偶在測量溫度時產生的溫度誤差,熱電偶也只能測出燒成溫度中的輻射熱,無法測量出窯具的傳導熱和具體的保溫時間以及實際燒成氣氛的綜合熱效應。這時若在燒制前或燒成中放置幾片測溫環,不僅可測出爐內的實際溫度而提前調整好爐溫,而且還能根據出爐后測溫環的直徑大小、顏色深淺以及形狀的變化等,體現出產品燒成的實際熱效應。 測溫環體積小巧、使用方便,不但對不同窯爐燒結的產品可作橫向比較,而且可將測試后的測溫環樣品和數據留存起來對不同時期燒結的產品作縱向比較,這樣對產品質量的追蹤提供了真實的歷史依據,對產品質量的嚴格管理更有保障。 |
2、利用測溫環解決窯爐橫向溫差偏大的問題 |
窯爐橫向溫差偏大,容易導致窯爐同一行出磚產生色差缺陷,這種色差常常呈逐漸過渡狀,一般不易區分開來,窯爐越寬,這種缺陷越明顯。其實對于溫差問題的解決方法是很多的。而難題在于如何準確知道窯爐內不同位置的溫差。試驗證明在拋光磚生產中,應盡量控制窯爐燒成帶橫向溫差≤5℃。 常用的測溫設備如測溫熱電偶僅設在窯爐的一側,對其橫向溫差不易檢測和控制,所以很難做到橫向溫度的均一。而通過使用測溫環,因其體積小巧,可準確測量不同位置的窯溫,得到窯爐內溫差的值。一方面彌補了熱電偶的不足,另一方面又測定了窯爐內三維空間熱分布狀況。 再通過合理設定各燒咀的風油(氣)比例,正確調節其閥門開度,及時補加耐火石棉等,防止窯墻漏風和不良的散熱,對于解決溫差的問題就容易得多了。 |
3、測溫環在箱式電爐中的應用 |
箱式電爐廣泛用于實驗室和小件產品的生產,因其投資小,使用靈活而成為燒成設備。由于電子陶瓷和現代精細陶瓷對燒成溫度非常敏感,溫度偏差3-5℃即可造成產品性能明顯差異,所以保證箱式爐內溫度的均勻性是十分必要的。實際使用中,因箱式爐發熱元件的設置不同,往往是中間溫度較均勻,四周溫度較不穩定。 一般情況下箱式爐都帶有熱電偶進行測溫,但因熱電偶放置空間的局限性,無法測量出爐內各個點的溫度,因此對于爐內溫差分布情況無法查明。對于燒成品的如何擺放,要進行較多次的試驗才能合理,但爐內放置產品的多少或品種發生變化后,溫差也會發生變化。因此需要一種簡單、方便的手段隨時測量出爐內各個角落的溫度。 |
4、測溫環在輥道窯中的應用 |
陶瓷制品在輥道窯里燒成,需要在特定的燒成制度下進行,合理的燒成制度是得到良好產品的根本保證。燒成制度包括溫度制度、壓力制度、氣氛制度,其中溫度制度*為關鍵。輥道窯的溫度監測主要是依靠沿窯長裝在窯頂或窯側的熱電偶所反映的溫度數據。 輥道窯一般分為預熱帶、燒成帶和冷卻帶,其中燒成帶溫度的檢測主要是確定燒成帶的*高溫度和高溫區間長度即制品在高溫下停留的時間,燒成帶的*高溫度是成瓷的*高溫度點,它直接影響到產品的生燒與過燒,高溫區的長度影響到保溫時間的長短,從而也影響到產品的質量。因此控制燒成溫度是保證產品質量的關鍵。有時熱電偶所指示的溫度達到了產品燒成的溫點,但因保溫時間的不同,產品也會產生很大的差別,原因在于熱電偶只測量其探頭所在位置的輻射熱,對于產品因保溫時間長短、窯具產生的傳導熱等綜合熱效應是無法記錄的。 測溫環可以記錄產品在燒成過程中所累積的全部熱效應。能提供一種有別于熱電偶等設備測量反映的產品燒成情況。是一種更貼近產品,更真實反映產品受熱的一種較好的測溫工具。 |
5、測溫環在立式窯燒結電子陶瓷中的應用 |
立式窯以其操作簡單,溫度均勻,燒結的連續性等優點而廣泛用于電子陶瓷的燒結。比如:瓷片電容、PTC陶瓷電阻器、氧化鋅壓敏電阻器以及PZT壓電陶瓷等。這些產品燒結溫度的準確性要求都較高,若同類產品在燒結過程中溫差過大,不但會影響產品的一致性,而且容易導致整批產品的報廢。 立式窯的熱電偶探頭一般布置在爐膛的外側,其測出的溫度不是產品燒結的實際溫度,這就要求產品在燒結前不但要知道其理論燒結溫度,更應了解爐膛內的實際溫度與表頭溫度的差異,否則依理論溫度調整過來的表頭溫度是難以燒出高質量的產品。此時采用校溫環提前校對一下爐膛內的溫度,不但可以減少物料的浪費,而且可以節省寶貴的試爐時間。 立式窯的連續性燒結又使得每爐產品在燒結過程中處于不可視狀態,為確保產品出爐后的質量,在每批產品的燒結過程中用測溫環來監控也就很有必要。考慮到熱電偶也與其它的儀器儀表一樣在使用一段時間后會老化或精度較低,加熱元件本身也是易老化,在電子陶瓷產品燒結中有規律地(比如每天1次)放入測溫環,就可監測燒結產品的爐溫變動狀態。從長遠來看,在立式窯中燒結產品使用校溫環作為監控手段,可以保證產品的質量和一致性。 |
6、測溫環在磁性材料中的應用 |
鎳鋅、錳鋅鈷、釹鐵硼等磁性材料的生產和研發過程中,需要對新型材料生產工藝溫度(預燒料溫度)進行擬定燒成溫度;對二次磁性材料產品燒結同樣需要準確的窯爐溫度,以便穩定磁性產品的電性能指標。窯爐一般是通過熱電偶傳遞窯爐溫度,但熱電偶因不同的生產商、不同的窯爐、不同的規格等因素,在同一企業內也較難統一測溫標準,容易出現研發部門測試的燒成溫度與生產部門的實際控溫不相符,給生產帶來不便。 測溫環能準確提供爐膛內部的實際溫度效應(即產品的累積熱效應),能對磁材產品所需的累積熱進行質量跟蹤,同時客觀記錄爐膛內每天的溫度變化情況,提供準確的數據信息,作為溫度質量跟蹤的檔案數據,有利于貫徹實施ISO的質量跟蹤管理體系,實現內部研發與生產控溫標準的統一,降低不同批原料帶來燒結溫度變化的復雜性。 |
![]() PTCR: a quality product from a quality source Worry-free firing control, day after day Ferro places great emphasis on the quality of PTCR rings - after all, the quality of the rings has a direct impact on the quality of our customers' products! All raw materials used in the powder mix from which the rings are manufactured undergo extensive laboratory testing. The powders are homogenized, and each individual batch is numbered and inspected once more, to guarantee both physical and pressingproperties. A unique batch identifier is pressed into each individual ring, allowing any ring to be traced back to its original powder batch, if necessary. As each batch of powder is released, the ring temperature conversion table is calculated - specifically for that batch. Ferro’s unique approach to temperature tables relieves PTCR users of the need to recalibrate or recalculate standard ring temperatures when introducing rings from a new batch. Since each individual PTCR ring can be relied on to perform as specified in the conversion table, absolute accuracy is always assured. The PTCR's accuracy, reliability and convenience free you from the concerns of firing quality and control - allowing you to concentrate on the quality of your product, not on temperature control. Process Temperature Control Rings: higher quality products and lower costs through improved,reliable firing control |
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測溫環使用注意事項 注意:為了使用時和方便,每個溫度表都是為該批環而特別制定的。為保證正確使用,請注意FERRO測溫環上所標的生產批號必須與溫度換算表上的保持一致。 |
Method of use Correct positioning is essential to allow accurate ring diameter reading in a single measurement. The special PTCR micrometers feature a positioning chuck that assists in placement of the ring, helping ensure that measurement is made correctly - across the middle digits of the ring number. |
測溫環對照表校正曲線圖下載: |