Assign GL account to Material automatically in ME21N

We manufacture industrial roofing and our Contracts division can handle the complete development of big sheds i.e. warehouses etc. Throughout a contract many purchases are made for site "goods" e.g. plant hire etc.

For purchasing on the Contract, we use Framework/Blanket orders and each Material used is really a Cost Head that is associated with a relevant GL account. This account number is entered via Account Assignment in ME21N. However, on many occasions the account number is entered incorrectly.

Is there a way of linking a GL account number directly to a Material so the GL account can be picked up automatically when the Material is entered in ME21N to get round the errors made?

Thanks

JIm Jackson