INTUC union said the 37 permanent and 40 contract workers became agitated after seeing the suspension work notice at the gate of Castle Industries Ltd this noon and started demonstration.
Company sources said, the small unit, which manufactured some railway equipment like railings had been incurring losses for want of order with advent of new technology in past one year.
"We have approached the West Bengal Labour Commissioner for a tripartite meeting on Tuesday next," the union sources said.