石膏的应用非常广泛，在建材行业生产中如何挑选好的石膏粉呢？下面就让济南石膏粉厂家为您讲一讲有关方法吧。

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.

从外观上判断

Judging from appearance

通过外观上观察和手感可初步判断石膏粉质量的优劣。就是看石膏粉的外观颜色，手感就是用手搓一搓石膏粉的糙细程度(细度）。

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.

外观上看，白度高的石膏粉细度目数高，质量好，价格较高；而发灰发黑、里面有黑色杂质的石膏粉质量较差。用手的拇指和食指搓捻石膏粉,手感发沙粗糙的石膏粉细度糙，质量较差、价格较低；而手感细腻的石音粉说明细度细，质量较好，价格也会较高。

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.

 

 

测定结晶水含量

Determination of crystal water content

根据经验和资料介绍,通过测定结晶水的含量，可判断石膏粉质量的好坏。一般合格的石膏粉结晶水的含量在4.5?5.5%之间^若石膏粉的结晶水含量远低于此标准值,则说明石膏粉过烧,注模时凝结时间太长甚至不凝固;若石膏粉的结晶水含量远高于此标准值，则说明石膏粉欠火或者受潮,注模时凝结时间短。以上两种情况的石膏粉都不合格,在生产中不能使用。

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.

检测石膏粉结晶水含量的方法是：精确称取4(TC烘干后冷却至室温的试样质量G(—般为2?5g),放置于恒重的铂金坩埚（或瓷坩埚）中，精确称取其质量为G1;在230±5°C下灼烧2h，取出移人干燥器内，冷却至室温后称取其质量为G2，则其结晶水百分含量为(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%.

生产中试注

Pilot injection in production

按生产中石膏和水的比例，确保所采用的器具、操作人员、设备和工艺方法一致，选择一个小型胎型母模进行生产模型的试注，与生产中正常使用的合格石膏粉的模型浇注过程进行对比。若待测石裔粉凝结时间正常合理、操作顺利不注桶，则说明该石膏粉是合格的石膏粉;若待测石膏粉凝结时间非正常，凝结时间太短注桶，或者凝结时间太长甚至不凝固，这样的石膏粉不合格，生产中不能使用。

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.

在建材行业生产中挑选好的石膏粉的方法在此讲了三种，如果您对此有需求可以来我们网站https://www.jnfhjc.com进行咨询了解。

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 https://www.jnfhjc.com Consult and understand.