Lincoln Electric IM687 manual TIG Welding Problems

E-5		TROUBLESHOOTING	E-5
	Observe all Safety Guidelines detailed throughout this manual
	PROBLEMS	POSSIBLE AREAS OF	RECOMMENDED
	(SYMPTOMS)	MISADJUSTMENTS	COURSE OF ACTION

TIG WELDING PROBLEMS

Black areas along weld bead.	1.	Clean any oily or organic conta-
		mination from the work piece.
	2.	Tungsten electrode may be cont-
		aminated. Replace or sharpen.
	3.	Check for contaminated gas or
		leaks in the gas line, torch, or
		connections
	4.	Gas shielding may be insuffi-
		cient. Increase gas flow; reduce
		tungsten stickout beyond gas
		cup.
Weak high frequency - machine has	1.	Check for poor connections in
normal welding output.		the welding circuit.
	2.	Gas shielding may be insuffi-
		cient. Increase gas flow; reduce
		tungsten stickout beyond gas
		cup.
	3.	Check for work and electrode
		cables in poor condition allowing
		high frequency to “Leak Off”.
	4.	Keep cables as short as possible.
	5.	Check Spark Gap operation and
		setting (0.015”)
High frequency “spark” is present at	1.	The tungsten electrode may be
tungsten electrode, but operator is		contaminated. Replace or sharp-
		en.
unable to establish a welding arc.
Machine has normal open circuit	2.	The current control may be set
voltage (refer to Technical		too low.
Specifications in the Installation	3.	The tungsten electrode may be
Chapter).
		too large for the process.
	4.	If a helium blend is used as a
		shielding gas, then reduce the
		percentage of helium.

Contact your Local Lincoln Authorized Field Service Facility for technical

troubleshooting assistance.

CAUTION

If for any reason you do not understand the test procedures or are unable to perform the tests/repairs safely, contact your Local Lincoln Authorized Field Service Facility for technical troubleshooting assistance before you proceed.

SQUARE WAVE TIG 175 PRO