?? ????????2000??????????????
????:1????????????:?????????
2????????
3??????vx
4???????
5?????????
1????????17???????????,???????????????????????????????????(????“????????????????”)??????????????,???????,??2000?????
????,?,??????????????????“?????????”,??,??,?????,???????????????
????,???2000?,???????????????10000psi(????),???690??????,?46?,??????????????????30?????????????????????,???????????????????????????????(??????? ????:??????)
????????:???????????