压滤机入料泵由泵壳、叶轮、副叶轮、护板、进料体、泵轴、联轴器、密封件等部件构成，其中泵壳、叶轮、护板、进料体等属于过流部件，依据保送的物料的磨蚀性、酸碱度，过流部件需采用不同的材质铸造。
灰口铸铁国标代号为HT，常见三种型号HT150、HT200、HT250。压滤机泵的底座等不重要的配件通常用HT150，托架泵壳等次要配件常用HT200，叶轮护板等重要配件常用HT250。
不锈钢材质由于其耐腐蚀性好，特别是耐酸性能，化工行业的压滤机专用泵通常会采用不锈钢铸造，常见的不锈钢材质有304、316、316L。不锈钢由于含有多种化学元素，依据元素的差异，不锈钢还分为奥氏体不锈钢和马氏体不锈钢，其主要区别在于耐腐蚀性和硬度不同，奥氏体耐腐蚀效果好，马氏体硬度高。
近些年随着科技的开展氟塑料这种材质应用越来越普遍，常见的有氟塑料管道和氟塑料泵，压滤机入料泵运用氟塑料内衬的优势极为明显，即耐酸又耐碱，特别是针对强酸强碱，氟塑料泵作用不可替代。
The feed pump of the filter press is composed of pump shell, impeller, auxiliary impeller, guard plate, feed body, pump shaft, coupling, seal and other parts. Among them, the pump shell, impeller, guard plate and feed body belong to overflow parts. According to the abrasiveness and pH of the transported materials, the overflow parts need to be cast with different materials.
Common pump casting materials are as follows:
Material of feed pump of filter press
1. Cast iron, cast iron materials are divided into two categories: gray cast iron and nodular cast iron.
The national standard code of gray cast iron is HT, and there are three common models HT150, HT200 and HT250. HT150 is usually used for unimportant accessories such as the base of filter press pump, HT200 is commonly used for secondary accessories such as bracket pump shell, and HT250 is commonly used for important accessories such as impeller guard plate.
The national standard code of nodular cast iron is QT, which is superior to gray cast iron and close to cast steel. The common models are QT450-10, QT500-7 and QT600-3.
2. Cast steel
The strength of cast steel is higher and can withstand greater pressure. The national standard code is ZG and the common model is zg230-450.
3. Stainless steel
Stainless steel material because of its good corrosion resistance, especially acid resistance, the special pump for filter press in chemical industry is usually cast in stainless steel. The common stainless steel materials are 304, 316 and 316L. Stainless steel contains a variety of chemical elements. According to the difference of elements, stainless steel is also divided into austenitic stainless steel and martensitic stainless steel. The main difference lies in different corrosion resistance and hardness. Austenitic corrosion resistance is good and martensitic hardness is high.
4. Alloy steel
The proportion of alloy elements in alloy steel is much higher than that of ordinary steel. The most representative is Cr40 alloy steel, which is usually used to make pump shaft because of its ultra-high strength.
5. Non metallic material
In recent years, with the development of science and technology, fluoroplastics are more and more widely used. The common fluoroplastics pipes and fluoroplastics pumps. The advantage of using fluoroplastics lining in the feed pump of filter press is very obvious, that is, acid and alkali resistance. Especially for strong acid and alkali, the function of fluoroplastics pump can not be replaced.
