TY JOUR TI ANALYSIS OF METHODS FOR MAKING A ROOT BEAD TO ENSURE LEAK PROOFNESS OF CHEMICAL EQUIPMENT WELDED JOINTS KW technology KW welding KW flux KW layer KW seam KW heating KW backing KW joints JO Transport engineering AU Bludov, A.N. AU Kharlamov, D.A. PY 2026 IS 2026 PB Bryansk State Technical University