我厂生产的主要产品有4AJ15-1型、2AL15-1型氨压缩机和4FS7B型制冷压缩机等.这三种产品的曲轴连杆采用球墨铸铁,1979年,我厂曾对Sn球铁进行了初步试验.处理Sn球铁42包水,从机械性能来看,Sn球铁铸态的最低抗拉强度是普通球铁的最高抗拉强度,平均要高6~8kg/mm~2,延伸率没有明显的下降,仍然保持较高值,硬度HB有较明显的提高. The main products of our factory are 4AJ15-1 type, 2AL15-1 type ammonia compressor, 4FS7B type refrigeration compressor, etc. The crankshaft connecting rod of these three products is made of ductile iron, and in 1979, our factory once performed on Sn ductile iron In the preliminary test, the Sn-Sn-42 water was treated. From the mechanical properties, the lowest tensile strength of Sn-Sn as-cast was the highest tensile strength of ordinary ductile iron with an average of 6-8 kg / mm ~ 2 Rate no significant decline, still maintain a high value, the hardness of HB have more obvious improvement.