4.1 Ball Valve structure is shown in Fig. 1. 4.2 List the major components and materials shown in Table 1:

On June 20,2015 guests of Pakistan came to our company (Stard Minli Valve),conducted a field study and inspection the product.At the same time discuss the next cooperation. This to China,guests were

离心机内腔中的固、液、气相不得与操作人员、外部环境产生交叉污染。一般而言，使用方在订货时应告知离心机制造商，提出密封要求。