diff --git a/gb28181-sip/src/main/java/cn/skcks/docking/gb28181/sip/generic/SipBuilder.java b/gb28181-sip/src/main/java/cn/skcks/docking/gb28181/sip/generic/SipBuilder.java
index 2e00242..a5124aa 100644
--- a/gb28181-sip/src/main/java/cn/skcks/docking/gb28181/sip/generic/SipBuilder.java
+++ b/gb28181-sip/src/main/java/cn/skcks/docking/gb28181/sip/generic/SipBuilder.java
@@ -14,7 +14,6 @@ import javax.sip.address.AddressFactory;
 import javax.sip.address.SipURI;
 import javax.sip.header.*;
 import javax.sip.message.MessageFactory;
-import java.nio.charset.Charset;
 import java.util.Arrays;
 import java.util.Collections;
 import java.util.List;
@@ -145,6 +144,11 @@ public class SipBuilder {
         return getHeaderFactory().createExpiresHeader(expires);
     }
 
+    @SneakyThrows
+    public static EventHeader createExpiresHeader(String event){
+        return getHeaderFactory().createEventHeader(event);
+    }
+
     @SneakyThrows
     public static XGBVerHeader createXGBVerHeader(int m,int n){
         return new XGBVerHeaderImpl(m,n);