无换向架链条抽油机的链条承受的总拉力为悬点载荷与平衡重的差值加连杆对链条的水平分力在链条上形成的附加拉力之和，受力状况优于普通链条抽油机，且能得到控制。
The force conditions of the chain on a chain drive pumping unit without reverse rack are much more favorable than that on conventional chain drive pumping units, and can be well controlled.
这些措施改善了整机受力状况，提高了链条寿命，减少了换向冲击和导轨磨损。
Therefore the force condition of the mechanism is improved, and the service life of the drive chain is prolonged, thereveral impact and wear of the guide are reduced.
这些措施改善了整机受力状况，提高了链条寿命，减少了换向冲击和导轨磨损。
Therefore the force condition of the mechanism is improved, and the service life of the drive chain is prolonged, thereveral impact and wear of the guide are reduced.
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