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Which one is gramatically correct?

A wide range of materials is/are used for the manufacture of our pipeline products.

If I consider that "a wide range" is the gramatical subject of the sentence, it should be followed by "is" but if I consider that "materials" is the gramatical subject, "are" should be used.

In such cases, can I rewirte to avoid confusion as follows?:

Materials in a wide range are used for the manufacture of our pipeline products. (Is this gramatically okay and natural?)
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Unfortunately, your revision is not so natural or smooth as the original; however, you can use either is or are and no one will notice, because the choice can be based on grammatical, notional, or proximal concord.
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SnappyA wide range of materials is used for the manufacture of our pipeline products.
The grammatical subject is "range." "Materials" is the object of a preposition, and cannot also be a subject.

You can say with some specifics:

Many materials, ranging from plastics to metals are used ...

or your other re-write is OK, too.

Regards,
A-Emotion: stars