| 摘要 |
An apparatus for preventing pollution of underground water tube well is provided to facilitate assembly of a head and a casing by tapering contact surfaces between the head and the casing and forming a water passage around the contact surface of the head. An apparatus for preventing pollution of underground water tube well comprises a head(110), a casing(120), and a cover(130). The casing includes a first tapered contact surface(113), and a first water passage(114). The first water passage is formed from the tapered contact surface to the lateral wall. The upper part of the head is sealed. The casing is mounted on the top of a well casing. The head includes a second upper and lower tapered contact surface(121,122), a second water passage(123), and a water pumping passage(124). The second tapered contact surface contacts with the first contact surface of the casing. The second water passage is formed between the second upper tapered contact surface and the second. The water pumping passage is communicated with the water passage and with a water pumping pipe(Pin). |
