Screening 是总生产中最重要的部分之一吗. It takes place before and/or after the crushing stage (or stages) and produces the specifications required of the final products.
The purpose of screening is to separate a flow of aggregate particles into uniform sizes. 这是通过使用实现的 振动屏幕.
什么是振动筛?
振动屏幕 are machines used to separate aggregates by particle size by means of an exciting force applied to the machine. 振动把材料提起来, 使它分层, allowing the smaller material to move from the top of the depth of material to the bottom of the material, 从而使它们暴露在筛选表面上.
骨料振动筛的种类
There are two main types of aggregate vibrating screens for dry screening applications:
- 横屏
- 倾斜屏幕
The primary difference between 横屏 and 倾斜屏幕 is the Inclined Screen uses gravity to help with the flow and conveyance of the feed material.
然而，这两种屏幕都为各种应用程序提供了优势.
倾斜屏幕
倾斜屏幕 最流行的聚合应用程序是什么. They are installed on an incline (anywhere from 5-45 degrees depending on the type of screen and the required cut) and employ the use of gravity to propel material down the screen. Since gravity helps to move the material, this type of screen requires low energy and low stroke.
横屏
横屏 are run flat at zero degrees but can be inclined or declined as much as 10 degrees in either direction. 因为它们不依赖重力来推动物质前进, 水平筛需要更高的能量和更大的冲程.
These types of screens are ideal for low-profile applications where height requirements are limited, 这使得它们成为便携式植物的绝佳选择. In stationary plants, they are often used as tertiary or finishing screens. Finer screening applications can greatly benefit from this type of screen.
Known for their efficiency and reliability, 横屏 offer more accurate particle sizing. 移动材料所需的高重力确保 屏幕堵塞 几乎消除，允许更连续的开放区域. The flat orientation of the Horizontal Screen allows material to be retained on the screen longer for higher efficiency. 这也使它们成为湿筛应用的一个很好的选择.
如何选择合适的聚合屏
Because screening plays such an important role in producing the required specifications of a final product, 当务之急是 选择右屏幕 for the job.
振动筛的选择是基于以下因素:
- 每小时最大吨数
- 原料的分级
- 材料的种类和重量
- 所需的分离尺寸
- 材料表面的水分
- 有什么特殊操作要求吗?, 包括饲料的物理特性或菠菜网最稳定正规平台_最全菠菜网大全要求
给振动筛上浆
振动筛有多种尺寸. 它们的宽度从4英尺到12英尺，长度从6英尺到32英尺. The width of the screen determines the carrying capacity of the screen deck, 而屏幕的长度决定了整体 筛效率. 通常，屏幕的长度为2.宽度的5 ~ 3倍大小.
每个制造商都有自己的屏幕尺寸公式. 筛管是根据以下因素定制的:
- Basic capacity – how much material is going to pass through a certain opening
- 倾斜——如果有的话，倾斜的程度是多少
- 甲板-并不是所有下层甲板的长度都可以被利用, as material has already traveled down some length of the upper decks before reaching the lower ones
- 尺寸过大-甲板上应该放多少材料
- Half size – how much material is half the size of the media opening With a high percentage of half size, the probability of the material passing through the screen openings will be higher, 屏幕的效率也会大大提高.
- 插槽-屏幕上的开口有多大
- Condition – applies to both the feed material and the atmosphere around the plant. 材料是湿的和粘的吗? 粘土含量高吗? 外面的温度是多少? 气候是潮湿的还是干燥的?
- Shape – Round or cubical particles have a higher chance of passing through the screen openings than a flat, elongated particle that has to find just the right position to fall through
- 重量-材料的密度
- 开放区域-屏幕上更开放的区域, the better the chance particles will find an opportunity to pass through
我的振动筛需要几层?
振动筛可以配置为一层、两层、三层或四层. Some fine screening operations can even have as many as eight screening decks. 三层甲板在综合工业中很常见, but the number of screen decks depends on the number of products the site needs to make.
在制造多种菠菜网最稳定正规平台_最全菠菜网大全的典型应用中, 筛网的顶板进行粗切, the middle deck(s) makes a middle cut and the bottom deck(s) make the fine cut.
Each screen deck is covered with screen media containing the openings for the particles to pass through. 屏幕媒体有许多不同的形式 屏幕媒体类型 对筛分效率起着重要的作用.
什么类型的屏幕介质最适合我的振动筛?
Screen media is all about open area, or the number of openings in the screen. 屏幕上的开口越多, the more opportunities the particles will have to pass through and the more efficient the screen will be.
However, more openings in the screen can decrease the wear life of the media. The correct screen media for an application will balance both wear life and efficiency.
用于聚合应用程序的常见屏幕媒体类型包括:
- Woven wire
- Polyurethane
- Rubber
- Hybrid
Wove wire cloth is the most consistent, versatile performing media product. It averages 50-70% open surface area in most configurations and provides the most flexibility for operations that need to make frequent media changeouts due to varying product specifications. 该介质的整体筛分效率较好.
Wire media
Polyurethane is better suited for wet/wash screens and dry applications with highly abrasive materials. It provides 30-40% less open area than wire cloth; however, 聚氨酯提供比线材更长的磨损寿命.
聚氨酯媒体
Rubber media is used for heavier, coarser materials that can damage standard wire screens. 它最常用于干燥应用或磨料材料. 橡胶介质的开口比钢丝布少, and therefore less throughput; however, 它们比金属丝网耐用得多.
Rubber media
Hybrid media combines wire screen with reinforced rubber or urethane strips to fit screen supports. It is highly popular in dry screening applications with high moisture materials and a high proportion of fines. 这种类型的媒体消除了盲目和挂钩, 哪端需要停止生产来清洗筛网. It provides more open area than polyurethane and lasts longer than woven wire. Depending on the application, production can increase 40% using hybrid screen media.
为聚合操作调整尺寸和选择振动筛时, be sure to provide the manufacturer with as much accurate detail about the feed material and the application as possible. From there, they can recommend what type of screen (Inclined or Horizontal) is best for the site, as well as the number of decks required and the 屏幕媒体类型 that will provide the best wear life and efficiency.
