The Problem With Outside Corner Welds
On flat-bottom and LNG storage tanks, the annular plate overhangs the shell plate by a minimum of 2″ / 50mm. That overhang leaves the LT7 without enough surface to run on using its standard configuration. The result without the right attachment is a manual weld at the tank base, slower, less consistent, and harder to inspect against code requirements.
What the Attachment Does
The LT7 magnetic device bolts to the LT7’s existing lifting point. No machining. No additional hardware. The magnetic assembly holds the machine against the annular plate overhang and keeps it tracking along the outside flange through the full corner weld sequence. A downloadable installation guide is linked at the top of this page.
Where It Fits in the Workflow
This attachment is designed for use at the tank base, after shell plate fit-up, when the outside corner weld needs to be completed with automated passes. It works within the same workflow where Tank Welding LLC.’s automatic girth welder handles horizontal shell seam welding higher up the tank, keeping the full construction sequence automated from bottom to top.
- Flat-bottom storage tanks with the standard minimum of 2″ / 50mm annular plate overhang
- LNG tank construction requiring consistent outside corner weld profiles
- Sites where the LT7 is already in use for girth or seam welding
To discuss ordering the LT7 welding accessory as a standalone unit or as part of a broader LT7 package, contact Tank Welding LLC. directly for factory-direct pricing.
The LT7 magnetic device bolts onto the LT7 lifting point so the LT7 can travel on 2″ (50mm) of plate that extends past the shell plate and welding the outside tank corner weld.
LT7 Magnetic Attachment kit installation guide 09.30.2021
Tank Welding LLC.
Is your complete source for Automatic Storage Tank Welding Machines. We specialize in custom built to order automatic tank welding machines for LNG & flat bottom tanks. We have multiple standard site proven Automatic Girth Welder designs (AGW) / 3 O’clock Welder designs. Single pass gas shielded EGW (Electrogas Welder), single pass self shielded VUP / vertical UP Welders & AVW / multiple pass Automatic Vert Welders, Automatic Vert Buggy, Shell Buggy, Tank Jacking Equipment and complete Tank Jacking systems, automatic curved plate welders for pressure vessel / sphere / digester welding. This line of equipment is built with your choice of USA made Lincoln or Miller welding systems. The AGW travel is powered by top of the line twin German engineered inverter controlled drive motors.
Explore all of our merchandise and contact us by phone or email. https://tankwelding.com/about-us/
Frequently Asked Questions
Does this attachment require any changes to the LT7 base unit?
No. The LT7 magnetic device uses the LT7’s existing lifting point as its mounting location. Units already in the field can be fitted with this attachment without any modifications.
Is this attachment specific to a certain tank diameter or size?
The device is rated for a minimum of 2″ / 50mm annular plate overhang. Suitability for a specific tank configuration is best confirmed with Tank Welding LLC. before ordering.
Can the magnetic device and the LT7 Seam Tracking Attachment be run together?
They serve different functions and are not designed for simultaneous use. The seam tracking attachment guides the weld torch along a seam; the magnetic device provides the machine’s footing on the annular plate overhang. Contact Tank Welding LLC. to determine which accessories apply to your scope of work.
How is the installation guide delivered?
A PDF guide is included with every LT7 welding accessory order and is available for download on this page. Installation is field-serviceable and does not require specialized equipment.
How do I get pricing or lead time information?
Tank Welding LLC. sells factory-direct. Use the contact information on this page to reach the team directly for pricing, order details, and lead times on this attachment or any other LT7 accessories
