石膏的應用非常廣泛，在建材行業生產中如何挑選好的石膏粉呢？下面就讓濟南石膏粉廠家為您講一講有關方法吧。

Gypsum is widely used. How to choose a good gypsum powder in the production of building materials industry? Now let Jinan gypsum powder manufacturer tell you about the relevant methods.

從外觀上判斷

Judging from appearance

通過外觀上觀察和手感可初步判斷石膏粉質量的優劣。就是看石膏粉的外觀顏色，手感就是用手搓一搓石膏粉的糙細程度(細度）。

The quality of gypsum powder can be preliminarily judged by appearance observation and hand feeling. It depends on the appearance and color of gypsum powder. The feel is to rub the roughness (fineness) of gypsum powder with your hands.

外觀上看，白度高的石膏粉細度目數高，質量好，價格較高；而發灰發黑、里面有黑色雜質的石膏粉質量較差。用手的拇指和食指搓捻石膏粉,手感發沙粗糙的石膏粉細度糙，質量較差、價格較低；而手感細膩的石音粉說明細度細，質量較好，價格也會較高。

In appearance, gypsum powder with high whiteness has high fineness, mesh number, good quality and high price; The gypsum powder with grey and black hair and black impurities inside is of poor quality. Twist the gypsum powder with the thumb and index finger of the hand. The gypsum powder that feels Sandy and rough has rough fineness, poor quality and low price; The stone tone powder with fine hand feel shows that it has fine fineness, good quality and high price.

 

 

測定結晶水含量

Determination of crystal water content

根據經驗和資料介紹,通過測定結晶水的含量，可判斷石膏粉質量的好壞。一般合格的石膏粉結晶水的含量在4.5?5.5%之間^若石膏粉的結晶水含量遠低于此標準值,則說明石膏粉過燒,注模時凝結時間太長甚至不凝固;若石膏粉的結晶水含量遠高于此標準值，則說明石膏粉欠火或者受潮,注模時凝結時間短。以上兩種情況的石膏粉都不合格,在生產中不能使用。

According to experience and information, the quality of gypsum powder can be judged by measuring the content of crystal water. Generally, the content of qualified gypsum powder crystal water is 4.5? 5.5%. If the crystal water content of gypsum powder is far lower than this standard value, it indicates that the gypsum powder is burned, and the setting time is too long or even does not solidify during injection molding; If the crystal water content of gypsum powder is much higher than this standard value, it indicates that gypsum powder is under fire or damp, and the setting time is short during injection molding. The gypsum powder in the above two cases is unqualified and cannot be used in production.

檢測石膏粉結晶水含量的方法是：精確稱取4(TC烘干后冷卻至室溫的試樣質量G(—般為2?5g),放置于恒重的鉑金坩堝（或瓷坩堝）中，精確稱取其質量為G1;在230±5°C下灼燒2h，取出移人干燥器內，冷卻至室溫后稱取其質量為G2，則其結晶水百分含量為(Gt—G2)/GX100%。

The method to detect the crystal water content of gypsum powder is: accurately weigh 4 (the mass g of the sample cooled to room temperature after TC drying (generally 2? 5g), place it in a platinum crucible (or porcelain crucible) with constant weight, and accurately weigh its mass as G1; Burn it at 230 ± 5 ° C for 2h, take it out and transfer it to the dryer. After cooling to room temperature, weigh its mass as G2, and then the percentage content of crystal water is (gt-g2) /gx100%.

生產中試注

Pilot injection in production

按生產中石膏和水的比例，確保所采用的器具、操作人員、設備和工藝方法一致，選擇一個小型胎型母模進行生產模型的試注，與生產中正常使用的合格石膏粉的模型澆注過程進行對比。若待測石裔粉凝結時間正常合理、操作順利不注桶，則說明該石膏粉是合格的石膏粉;若待測石膏粉凝結時間非正常，凝結時間太短注桶，或者凝結時間太長甚至不凝固，這樣的石膏粉不合格，生產中不能使用。

According to the proportion of gypsum and water in production, ensure that the appliances, operators, equipment and process methods used are consistent, select a small tire master mold for trial injection of the production model, and compare it with the model pouring process of qualified gypsum powder normally used in production. If the setting time of the stone powder to be tested is normal and reasonable, the operation is smooth, and the bucket is not injected, it indicates that the gypsum powder is qualified gypsum powder; If the setting time of the gypsum powder to be tested is abnormal, the setting time is too short, or the setting time is too long or even does not set, such gypsum powder is unqualified and cannot be used in production.

在建材行業生產中挑選好的石膏粉的方法在此講了三種，如果您對此有需求可以來我們網站http://m.man5g.cn進行咨詢了解。

Here are three ways to select good gypsum powder in the production of building materials industry. If you have a demand for it, you can come to our website http://m.man5g.cn Consult and understand.