Lincoln Electric LT-7 User Manual

Description

Output Input

Submerged Arc

LT-7 Tractor

Submerged Arc DC Wire Feeder

The LT-7 Tractor is a self-propelled mechanized wire feeder, designed for the
submerged arc process with track system capabilities. It is self-guiding and
easy to operate – only one operator is usually required. It is designed to be
used with a variety of Lincoln DC constant voltage and constant current power
sources. The rugged, lightweight unit permits quick movement to the next joint.
Its compact size fits through small openings and confined spaces. Butt and
fillet welds can be made on heavy plate or steel as light as 12 gauge (2.5mm).
The LT-7 Tractor is ideal for the following applications: ship and barge building,
storage tank erection, bridge deck installation, beam, girder or column
fabrication, and long seams on heavy weldments.

Publication E9.70 12/03

www.lincolnelectric.com

Processes

Advantage Lincoln

Order

TECHNICAL SPECIFICATIONS

Recommended General Options

• LT-7 Tractor feeds 3/32 to 3/16” (2.4 to 4.8 mm) solid wires,
from 100 - 400 inches per minute (2.5 - 10.2 m/min) wire feed
speed.

• Calibrated tractor drive adjusts travel speeds from 6 to 70
inches per minute (0.12 to 1.8 m/min).

• Vertical head lift adjuster for adjusting electrical stickout from
1/2 in. to 5 in. (12.7 to 127.0 mm).

• Weld angle is up to 50° from vertical on either side; drag
angle is up to 30° from vertical.

• Control box is conveniently located on the tractor (can be
mounted either left or right), eliminating the need to return to
the power source for routine procedure changes.

• Exceptional tracking control and self-steering in most
applications leave the operator free for quality control, joint
cleaning and flux handling.

• Welds butts, horizontal fillet and lap joints to the left or right
side of the tractor frame for convenience.

• Close mechanical alignment between wire and joint maximizes
weld quality with no fixturing costs.

• Three-year warranty on parts and labor.

Recommended Power Sources

AUTOMATIC WIRE FEEDERS

11 5

VAC

K227-1 LT-7 Standard Model
K395-1 LT-7 Track Model

Wire Feeder Control Cable Extensions, Adapter Cable, Linc-Fill™
Attachments, Horizontal Fillet and Lap Adapter Kit, Flat Fillet Adapter
Kit, Butt Seam Guide Kit, Track Conversion Kit, Tiny Twinarc

®

Adapter Kit, Track Section, Flux Screen, Magnetic Flux Screen
Separator, Concentric Flux Cone Assembly

Required Options

Control Cable, Weld Power Cable, Contact Nozzle Assembly

CV-655, DC-600, DC-655, DC-1000, DC-1500

Wire Feed Wire Size Range Dimensions Net

Product Product Input Rated Output Speed Range Solid H x W x D Weight

Name Number Power Current/Duty Cycle ipm (m/min) in. (mm) in. (mm) lbs. (kg)

LT-7 K227-1 115 VAC 600A/100% 100 - 400 3/32 - 3/16” 27.5 x 33 x 14 120

Standard 50/60 Hz 1100A/100% (with (2.5 - 10.2) (2.4 - 4.8) (698 x 838 x 356) (54)

LT-7 K395-1

water cooling)

130

Track (59)

Track Model Shown

LT-7 Tractor

www.lincolnelectric.com

[2]

A CLOSER LOOK

REQUIRED OPTIONS

PERFORMANCE

• Solid-state control system precisely regulates procedures for
reliable starting and economical welding.

• Automatic compensation for input voltage and tractor loading
variations.

• Function lights built into the solid-state printed circuit boards aid
troubleshooting to minimize down time.

• Cross seam adjuster speeds setup and lets operator track
irregular joints while welding. Adjustment range is 3-1/8 in.
(79 mm) with clamp and 2-1/2 in. (63 mm) with handwheel.

• To perform a curved weld, the minimum diameter can be as small
as 10 ft. (3.0m) for an inside weld and 13 ft. (3.9m) for an outside
weld.

• To perform an inside circumferential weld, the minimum inside
diameter that can be welded is approximately 5 ft. (1.5m).

QUALITY AND RELIABILITY

• Three-year warranty on parts and labor.

• Manufactured under a quality system certified to ISO 9001
requirements.

• Rugged and durable design recognized throughout the industry
for its long life and years of trouble-free wire feeding.

FEATURES

• Quick, easy installation of optional guides for different joints.

• Reel holds 60 lb. (27.2 kg) solid wire coils.

• Flux hopper capacity of 15 lbs. (6.8 kg). Includes a manual flux
flow rate control valve and can be mounted at four locations to
the left or right.

• Continuous Vertical Adjustment: 1-1/2” (38 mm) handweel
variation for ESO (electrical stickout).

• Travel clutch operates from either side of the tractor.

456

WELD POWER CABLES

CONTROL CABLES

Description Order No.

Wire Feeder Control Cable K1822-25 - 25 ft. (7.6m)

Wire Feeder Control Cable Extensions K1797-25 - 25 ft. (7.6m)

K1797-50 - 50 ft. (15.2m)

Adapter Cable for Control Cable K1798
to Terminal Strip Power Sources

Order No. Description

K1842-10 Lug to Lug, 3/0, 600A, 60% duty cycle, 10 ft. (3.0m)
K1842-35 Lug to Lug, 3/0, 600A, 60% duty cycle, 35 ft. (10.6m)
K1842-60 Lug to Lug, 3/0, 600A, 60% duty cycle, 60 ft. (18.2m)
K1842-110 Lug to Lug, 4/0, 600A, 60% duty cycle, 110 ft. (33.5m)

456

CONTACT NOZZLE ASSEMBLIES

Description/Diameter Wire Order No.

Submerged Arc:

3/32” (2.4 mm) K231-3/32
1/8” (3.2 mm) K231-1/8
5/32” (4.0 mm) K231-5/32
3/16” (4.8 mm) K231-3/16

Positive:

3/32 - 1/8” (2.4 - 3.2 mm) K148A
3/32 - 3/16” (2.4 - 4.8 mm) K148B

Linc-Fill™ Attachments for Positive Contact Nozzle Asbly

Extension for K148
3/32” (2.4 mm) K149-3/32
1/8” (3.2 mm) K149-1/8
5/32” (4.0 mm) K149-5/32