各位汽机专业大侠请进，我厂密封油主差压阀抖动，请问是什么原因？

<p><font size="4">我厂是2x300MW机组，发电机采用<span lang="EN-US" style="FONT-SIZE: 18pt; FONT-FAMILY: &quot;Times New Roman&quot;; mso-fareast-font-family: 宋体; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA;"><strong>YKG-300-2密封油系统，这几天机组检修完刚起来，今天中午在没有进行任何操作的情况下，CRT上显示氢油差压突然到0，空氢侧直流油泵联动，就地检查是发现空侧油压在0.1Mpa-0.6Mpa之间波动，主差压阀平凡动作，管道震动十分严重，关闭主差压阀信号门时停止摆动，在投运主差压阀后恢复正常，请各位大侠分析一下是什么原因？如何处理？谢谢！ </strong></span></font></p><p class="MsoNormal" align="center" style="MARGIN: 0cm 0cm 0pt; TEXT-ALIGN: center;"><b><span style="FONT-SIZE: 24pt; FONT-FAMILY: 宋体; mso-bidi-font-size: 12.0pt; mso-ascii-font-family: &quot;Times New Roman&quot;; mso-bidi-font-family: &quot;Times New Roman&quot;; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA; mso-hansi-font-family: &quot;Times New Roman&quot;;"><font size="1"></font></span></b></p>

<font size="4">我对<span lang="EN-US" style="FONT-SIZE: 18pt; FONT-FAMILY: 'mso-fareast-font-family:宋体;mso-font-kerning:1.0pt;mso-ansi-language:en-us;mso-fareast-language:zh-cn;mso-bidi-language:ar-sa;;;">YKG-300-2密封油系统并不了解，但觉得有机会时不妨检查主差压阀里面垫子的密封情况或许会有收获，阅者为师，相互交流！</span></font>

信号管检查一下？期待高人指点！