| 伞齿轮操作机构
Bevel Gear Actuators
许多实际应用要求闸阀、截止阀和截止止回阀采用齿轮装置来降低手轮的边缘拉力，使得靠一个人的力量就可以启闭阀门。参阅第2页了解边缘拉力的定义和计算方法。标准齿轮操作机构是根据启闭阀门所需的边缘拉力来选型的，适用于边缘拉力小于250磅的阀门。除非另有说明，最大压差被认为等于阀门的压力等级，例如，900
psi就是900磅压力等级阀门的最大压差。如果应用数据与上述不同，在订购时请咨询工厂。
Many applications require gate, globe and stop-check
valves to use gearing to reduce the hand wheel rimpull and thus allow
one man to manually seat or unseat the valve. See page 2
for definition and calculation of rimpull. Standard gear actuators are
sized to seat or unseat the valve with a rimpull requirement of less than
250 Ibs. Unless otherwise specified the maximum differential pressure
is assumed to equal the valve pressure class, e.g. 900 psi for a 900 lb.
class valve. If service parameters differ from above, please consult factory
when ordering.
如果已知实际最大压差，或者最大边缘拉力小于250磅，则请在您的询价单中注明这些资料。
When the actual maximum differential pressure
is known, or a maximum rimpull is specified which is less than 250Ibs,
this information should be provided in your Request for Quotation.
- 最大关闭压差
Maximum differential shut off pressure
- 启闭阀门的最大容许手轮边缘拉力
Maximum allowable handwheel rimpull to seat or
unseat valve
我们标准伞齿轮操作机构一般具有下列特征*：
Our standard bevel gear actuator typically includes
the following features*:
- 2英寸方形气动扳手螺母。
2" square air wrench nut.
- 全天候，适用于室外应用。
Weatherproof, built for outdoor service.
- 可适应电动执行机构。
Motor actuator adaptable.
- 可提供复合传动装置。
Compound gearing available.
* 在订购时请咨询工厂
* Consult factory when ordering
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主机
Base Unit |
复合伞齿轮操作机构附件
BGA Attachment |
正齿轮操作机构附件
SGA Attachment |
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手轮方位
Handwheel Orientation
可能的手轮方位如下图右侧所示。如果采用正齿轮(SGA)或复合伞齿轮(BGA)附件，则可以在图1中显示的各个位置安装手轮。典型配置如图2所示。
Possible handwheel orientations are shown in the
figure to the right below. Spur gear (SGA) or compound bevel gear (BGA)
attachments can be provided in any position shown in Figure 1. Typical
configurations are shown in Figure 2.
图1
Figure 1
伞齿轮的几条经验
Rules of Thumb for Bevel Gearing
- 一般来说，操作人员应该能够提起与他自己重量相同的物体，因此可以估算最大的边缘拉力。例如，一个175磅重的人，应该能够操作边缘拉力达到175磅的操作机构。为了避免操作人员过度疲劳和可能造成的伤害，通常情况下所确定的边缘拉力要远远小于175磅。
On the average, operators should be capable
of lifting their own weight, using this as a guide maximum rimpull
can be estimated, ie; a 175 Ib. man should be able to handle a
seating rimpull up to about 175 Ibs. Rimpulls are often specified
much lower to avoid operator strain and possible injury.
- 较低的边缘拉力的要求常常导致需要配置高齿轮传动比的伞齿轮操作机构。由于操作阀门时旋转的圈数增加，从而导致操作时间增加。在确定最大边缘拉力时要注意这一点。
Low rimpull requirements often result in
the selection of bevel gears with high gear ratios. This can result
in high operating times due to the number of turns needed to cycle
the valve. Keep this in mind when specifying a maximum rimpull.
- 气动扳手操作加快了高齿轮传动比伞齿轮装置的循环速度，但是，其伞齿轮的机械增益使得操作者可能对阀门造成破坏。没有阀座或后座的阀门采用气动扳手；手动阀座和后座阀门操作要小心，特别是在配置伞齿轮操作机构后。
Air wrench operation speeds up cycle time
on high gear ratio bevel gears however, the mechanical advantage
available from bevel gearing enables the operator to damage the
valve. Never seat or back seat the valve using an air wrench;
manually seat and back seat the valves with caution, especially
when equipped with bevel gears.
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