I take it that there is no pre-existing contractual relationship with an arbitration clause or a separate arbitration agreement. I also take it that there is a willingness on the part of both parties to the dispute to have the matter adjudicated through arbitration.
In that case, arbitration can only be instituted by taking recourse to Section 89 CPC. This will require the filing of a joint memo or application by the parties to the dispute to the Court since there is no pre-existing arbitration agreement. Otherwise, this cannot be referred to arbitration by a Court under Section 89. (Please see Kerala State Electricity Board and Anr. v. Kurien E. Kathil.)
As for the injunction, there are two ways of doing it:
1. Both parties agree to maintain the status quo and record and commit to this understanding in their joint memo or application; or
2. You move an application under Section 9 of the Arbitration and Conciliation Act for interim measures (read: injunction) before the Court. In that application, you can ask that the injunction already granted to you, as part of the the partition suit, be replicated by the way of an order for interim measures. That you already have an injunction in your favour should enure to your benefit. This way, you would be able to preserve the status quo during the arbitral proceedings.
I must point out that I don’t have the exact facts of the case and this is the best possible answer I could think of in light of the facts before me.
I hope you have your answer. Follow-up questions welcome!