Is there any way to use SRX for using for only incoming packages. I don't want to return traffic to SRX. If I change defaulte route of server to directly internet SRX drop the packeges because not in session table.
To understand the requirement better, does the Server have a route to the internet bypassing the firewall. If it does, you can simply disable syn-seq check and that should do the job.
If the return path from Server to Internet is also routed through the firewall, you can selectively bypass the return traffic from the flow module. In this case the firewall will simply act as a router, no firewalling services.