Tube and Pipe Equipment - Welded Tube Mill System

Roll-Kraft Welded Tube Mill System

Roll-Kraft's U-15HD Welded Tube Mill System combines heavy-duty construction, user-friendly controls and high precision roll-tooling in a low-cost platform. Every component is adaptable and configured to meet your welded tube or welded form requirements and budget specifications.

The system includes the following components:

• 8,000-lb Double End Uncoiler
• Roll Straightener / Flattener
• Coil End Joiner
• Roll-Kraft U-15HD Forming Mill (7 Stations)
• Weld Box
• O.D. Scarfing Unit
• Cooling / Filtration System w/Cooling Trough
• Roll-Kraft U-15HD Sizing Mill (7 Stations)
• Double Turkshead Unit
• Roll-Kraft 24" Flying Cut-off Saw (servo accelerated)
• Accessories

We engineer our tube mill systems "from the tube out," using the latest in Finite Element Analysis (FEA) software that optimizes the tooling design prior to manufacturing. Adjustments to the entire system are simple because the rugged forming and sizing mills are precision tuned with custom-designed electrical controls and HMI.

To view a video of the complete tube mill system or each segment in action, visit the Tube and Pipe Products section of the video gallery. For more details on each of the system components, please see below.

8,000-Lb. Double-End Uncoiler

Roll-Kraft provides the most affordable material handling equipment in the industry. Roll-Kraft specifies each uncoiler to meet the material and production requirements, and can be configured in ranges from 1,000 to 30,000-lb capacities.

• Double ended
• Dual hydraulic thread drives (push-button controlled)
• Hydraulic mandrel expansion
• Maximum coil width - 12c
• Maximum coil weight - 8,000 lbs. / side
• Coil I.D. - 16"- 20"
• Voltage at controls - 110 V

Powered Stock Leveler

Stock levelers remove the coil-set from the coiled material and greatly improve the straightness and formation of the final product (tube).

• Model PS300-7-12
• Maximum strip width - 12"
• Maximum stock thickness (full width) - 0.135"
• Maximum yield - 80 KSI
• Variable-speed loop control arm
• Heavy-duty 7-roll design
• Remote pendant for jog, forward, and reverse

Coil End Joiner

Utilizing a coil end joiner as part of a welded tube mill system saves time and money by minimizing scrap and labor in the threading of a new coil. These end joiners include a two-stage system that shears both ends of the coil and precisely welds both halves together with minimal weld bead and downtime. When combined with a stock accumulator, the transition from coil to coil occurs without stopping the remainder of the line.

• Model PSA 2000 (portable)
• Maximum strip width - 10"
• Minimum strip width - 2"
• Maximum strip thickness - 0.120"
• Minimum strip thickness - 0.030"
• Electrics - 230V or 460V
• Weld process - Tungsten arc (TIG)
• 25-degree shear and weld bias

Roll-Kraft U-15 HD Tube Mill – Forming Section

The Roll-Kraft U-15HD forming mill is ideally suited for tubes up to 3.5" diameter x .188" gauge metals up to 100KSI yield strength. The tube mill incorporates strong cast iron forming stands, precision bearings and adjustable bottom spindles, together with its' own motor and drive that is tuned with the sizing mill, welder and cut-off saw, to produce tubes at speeds of up to 150 FPM.

• 7 driven passes (4 breakdown, 3 fin)
• Roll space - 12"
• Spindle diameter - 3"
• Centerline bottom spindles - 8.50" adjustable
• Dual output pinion gear boxes with universal shafts
• 8 side pass stands with single centerline adjustment screw
• Weld box, 3-roll
• Tandem scarfing unit
• Bead winder – w/variable speed motor
• Pullover rolls
• Entry table mounted on main mill base
• Extended bed for welder, double scarf unit, weld box, and turkshead
• External coolant tank
• Cooling trough mounted between forming and sizing mill sections
• Light curtains on main mill base
• 100-HP motor, variable-speed drive, and controls (1 for forming, 1 for sizing)
• Optional raft plate configurations available

Weld Box (3-Roll)

A vital part of any well-designed high frequency welded tube mill is the tube and pipe welding unit. This fixture, in a 3-roll configuration, contains the perimeter of the tube by properly aligning and applying forging pressure to both strip edges, resulting in consistent weld penetration. Each roll is adjustable by independent clevis assemblies. The weld box upright and base plates have both vertical and lateral adjustment features.

• 3-Roll clevis' mounted to rotating face plate
• Welded construction
• Manual adjustment features – Vertical and lateral
• 0.5" – 3.5" Diameter tube range
• Custom configurations to suit other tube sizes
• 2, 4 & 6 roll weld boxes for HF, TIG and Laser welding systems available

Tandem O.D. Scarfing Unit

A tube and pipe scarfing station is equally vital to the production of a high-quality, HF-welded tube is the removal of the excess weld bead from the surface of the tube. An O.D. scarfing unit utilizes a cutting tool, mounted to an air actuated tool holder that applies sufficient force to scrape the excessive weld bead. The scarfing unit mounts immediately after the weld box to efficiently remove the weld bead while in a heated state, forming a continuous ribbon that is safely coiled for ease of disposal.

Roll-Kraft's standard scarfing unit includes a tandem head configuration, primary and secondary, mounted with separate actuators to quickly engage a secondary head when the primary head cutter becomes damaged.

• Tandem head configuration
• Air actuated cylinders to engage / disengage each head
• Tool holders are fine adjustable, with replaceable scarfing knives
• Motorized bead winder
• Welded construction
• Lower support rollers hold tube for consistent scarf
• Custom configurations available

Roll-Kraft U-15 HD Tube Mill – Sizing Section

The Roll-Kraft U-15HD Sizing Mill is configured to resize or reshape a tube to a specified geometry, using an independent motor and drive; tuned with the forming mill section that is ideally suited for tubes up to 3.5" diameter x .188" gauge metals up to 100KSI yield strength. The tube mill incorporates strong cast iron forming stands, precision bearings and adjustable bottom spindles for speeds up to 150 FPM.

• 7 sizing passes
• Roll space - 12"
• Spindle diameter - 3"
• Centerline bottom spindles - 8.50" adjustable
• Dual output pinion gear boxes with universal shafts
• 6 side pass stands with single centerline adjustment screw
• Seam orientation guide
• Double turkshead unit
• Extended bed for seam orientation stand & turkshead
• External coolant tank
• Cooling trough
• Light curtains on main mill base
• 100-HP motor, variable-speed drive, and controls (1 for forming, 1 for sizing)
• Optional raft plate configurations available

Double Turkshead Unit

Tube and Pipe Turkshead units are used to straighten round tube and pipe as well as reshape round tube into various other shapes. A double turkshead unit utilizes rollers mounted to clevises that contain the tube. The clevises are attached to a rotational face plate for axial straightening while the face plate mounts to a vertical and lateral upright frame assembly that adjusts for bow or camber. Available in both single and double head configurations, the double head generally provides the best results by working each head together to contain and manipulate the tube.

• Dual rotating head units
• Unit 1 – 4-roll configuration with individual clevises
• Unit 2 – 2-roll configuration with individual clevises
• Individual rotational, vertical & lateral adjustment features
• Welded construction
• 2, 4, 6 or 8 roll configurations available

Cooling/Filtration System and Cooling Trough

Our dedicated cooling and filtration systems are scaled to efficiently distribute coolant to each component of the tube mill system and filter our contaminants; together in a space saving configuration. The cooling trough station is mounted between the forming and sizing mills. It contains nylon bottom support rolls and a coolant manifold with multiple lines to distribute high volumes of coolant to the welded tube. The coolant is captured inside the fabricated tubular body and is returned to the filtration system. Two hinged access panels included.

• Deep bed filter, 8 square feet filter area
• 10" disc skimmer for floating tramp oil
• 460V motor contactor and circuit protector
• API plate and frame heat exchanger
• Coolant HE pump: 304 SS, 3/4-HP centrifugal pump
• DI HE pump: 304 SS 1.5-HP centrifugal pump
• Tower pump: 304 SS 2-HP centrifugal pump
• 15' cooling trough with nylon support rolls, cooling manifold & lines

24" Flying Cut-Off Saw

A friction-saw makes efficient cuts to almost any profile, on-the-fly, using a servo driven carriage and blade pivot unit. Heavy-duty blade guards, entry & exit tube clamping jaw system, internal blade cooling and coolant return make quick work of most welded products and are standard features of the Roll-Kraft Cut-off Saw.

• 24" saw blade
• Flying friction saw
• 30-HP blade pivot unit
• 20-HP servo driven unit
• Jaw sets consisting of upper entry, upper exit, lower entry, and lower exit clamps
• Cut lengths at or above 6' @ 100 FPM