暗楔法

The host produces: The wedge type gate valve, the bright pole coal gas gate valve, the gate valve, the electrodynamic balance-like double damper plate gate valve, the box thread gate valve, the bright pole underground gate valve, the electrically operated dark pole wedge type gate valve, seals the gate valve, the knife gate valve, the cut-off valve, the box thread cut-off valve (Japanese-style, Soviet type), to turn on lathe softly opens the type check valve, to risefall the check valve, the noise elimination check valve, to clamp the small dish shape check valve, the vertical check valve, to stand lies the dual purpose check valve, the small dish shape by-pass valve, the by-pass valve, the stopcock, the Three Contacts stopcock, the plunger valve, the ball valve, the flange reed valve.

主产：楔式闸阀、明杆煤气闸阀、闸阀、电动平衡式双闸板闸阀、内螺纹闸阀、明杆地下闸阀、电动暗杆楔式闸阀、软密封闸阀、刀型闸阀、截止阀、内螺纹截止阀、旋启式止回阀、升降止回阀、消声止回阀、对夹碟形止回阀、立式止回阀、立卧两用止回阀、碟形平衡阀、平衡阀、旋塞阀、三通旋塞阀、柱塞阀、球阀、法兰蝶阀。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。