有几个液压方面的名词请教英文翻译

1.电磁换向阀electromagnetic directional valve
（如果是强调用线圈做磁场，则为solenoid directional valve）

2. 叠加式液控单向阀stacked pilot-controlled check valve

3. 叠加式单向节流阀stacked one-way throttle valve

4. 叠加式溢流阀stacked discharge valve

5. 分流阀flow divider (valve)

electromagnetic converserble valve
overlapped fluid valve of single direction
overlapped saving valve of single direction
overlapped overflowing valve
distributing valve