1. In industries of: Shipbuilding, Crane, Bridge, Port Machinery, Construction Machinery... Special designed large machines are adopted to straighten on different WIP (Work in process) at different production stages: On ribbed plate and joint plate;
2. Importance: As niche products applied in niche market, these large heavy and complicated machines have small using quantity but critical role:
1. Stiffener Plate Unit, the other often used names include:
1) Stiffener Panel Unit;
2) Ribbed Plate Unit...;
Are basic components being fabricated into one of the most important workpieces: Large section Beam Plate Element, which are indispensable assemblies in process technology of various Production Line;
2. These large section Beam plate elements usually have specifications of:
1) Side plates thickness is from 8mm to 28mm;
2) Cross section height is from 1000mm to 1500 mm;
3) Cross section width is from 1500mm to 3000 mm,
4) The entire large section Beam plate element is in the total Length of 20m to 30m;
5) Structure of Stiffener Plate Unit: These large rectangular Beams are fabricated from stiffener plates, which is made up of one piece of large size steel plate, and welded with 1 to 3 pieces of Angle steels working as stiffeners in parallel on its top:
A piece of typical ribbed plate unit, that is straightened out of Wuxi JACK Stiffened Panel Straightening Machine: (Fig.1)
1) Deformation: Because of its long length and relatively small size, after being fabricated with Angle steels, there are exist 2 types of deformation on this ribbed plate unit:
a) Unevenness of base plate;
b) Longitudinal distortion of Angle Steels caused from welding operation heat input;
To be eligible for next step production, such deformed stiffener panels should be straightened specifically:
2) At Shipbuilding customer facility, a piece of 20m length Rib Plate unit, that is processed with Wuxi JACK J28 model Stiffened Plate Straightening Machine: (Fig.2)
1) Why Need this Machine? During producing these stiffener plates, after Angle steels are welded onto the base steel plate, the formed stiffener plate unit usually generate certain degree of deformation, which is caused from welding heat input. Wuxi JACK designed and produced J series Ribbed Plate Straightening Machine, is for flattening out these welded and deformed stiffener plates unit:
2) At Wuxi JACK workshop, engineer and technicians are having performance test on our J28 model machine, by means of trying to straighten on a piece of on stiffener panel unit: (Fig.3)
1. Usage: This is another more specific and special designed straightening machine, which, as its name suggests, is used for straightening any bulge up or upward deformation on joint steel plates, generated during steel plates flat butt welding, acquired from operation of MP models Steel Plate Butt Joint Welding Machine;
2. In this way, a piece of large and flattened steel plate can be eligible, being used in fabricating on components and assemblies of large machineries in Shipbuilding and Port Machinery:
3. Central work unit and workpiece (Joint plate) of Wuxi JACK JF16 model Steel Plate Butt Welding Seam Straightening Machine: (Fig.4)
4. JF16 model being tested on its plate butt welding seam straightening performance at Wuxi JACK workshop: (Fig.5)
1. Work Station: At various production lines, Wuxi JACK J series machine is applied following rib plate unit fabrication station, for straightening the deformed rib plate unit after welding;
A set of Wuxi JACK J20 model machine on straightening stiffener panel is being installed at a Shipbuilding customer plant based in Guangzhou: (Fig.6)
2. Another Usage: Besides, by means of straightening operation, rib plate units can have its stress relieved, which strengthen the integral strength of large section Beam Plate Element produced;
1) Base plate width: 1000 mm to 3000 mm;
2) Base plate thickness: 8 mm to 28 mm for J28 model;
3) Stiffener plate unit length can be from 20m to 30m as the maximum:
1) To fully guarantee reliable, consistent and accurate operation on ribbed plate and joint flat plate straightening, electric control on the entire operation is by means of encoder as feedback communication in closed loop electric circuit, and intuitive HMI (Human machine interface) operation:
2) Overhang type HMI operating station of Wuxi JACK J20/ J28 models machine, on controlling the 3 units of straightening mechanism on stiffener panel: (Fig.7)
The lefthand scrolling photos: Snapshots on producing Stiffened Plate Straightening Machine at Wuxi JACK workshop, its main components, assemblies, and function units
For straightening a piece of stiffener plate unit or joint plate effectively, Wuxi JACK produced J model Stiffened Panel Straightening Machine and JF models Plate Butt Welding Seam Straightening Machine should have mechanisms of:
1. Straightening units: There are 3 pieces of straightening units in one set of the J Series machine on straightening ribbed plate unit, and 1 piece of straightening unit in JF models machine on straightening plate butt welding seam. One set of the straightening mechanism consists of top assembled downward straightening head (Assembled with 3 straightening rollers), and bottom fixed straightening roller;
2. Straightening Unit Transverse Moving Mechanism: During machine operation, each piece of the straightening unit can be moved horizontally, to accommodate on different positions and widths of Angle steels (As stiffeners) on steel plate. There are soft electric limit switches and hard rubber stops, to manage on horizontal movement stroke of straightening units;
3. Bottom Support Rollers: During operation of the Stiffened Plate Straightening Machine, the bottom supporting rollers have 2 functions: Hold the workpiece (Stiffener plate unit), and send it forward during straightening operation. This work motion is driven under A.C. motor;
4. Electric Control System: Plays key role for operation of the Ribbed Plate Straightening Machine and Plate Butt Welding Seam Straightening Machine, advanced technology control, which distinguishes itself from encoder, proximity switch, and HMI.
1) Machine Models: There are 3 the most frequently selected models: J16, J20 and J28, which are distinguished from each other based on the max. thickness of ribbed plate unit base plate that can be straightened: 16mm, 20mm and 28mm;
2) Quantity of Straightening Unit: Correspond with quantity of Angle steels being fabricated onto the base plate, which is usually 3 to 4 pieces at the most, in one set of the Stiffened Plate Straightening Machine, there are 3 pieces of downward acting straightening rams. The interval between any adjacent Angle steels on base plate, which serve as stiffeners on plate, is in the range of 225 to 700 mm;
3) Drive Mode on Straightening Operation: In Wuxi JACK J and JF series machines, on stiffened plate unit and joint plate butt welding seam straightening, straightening task is driven with heavy force hydraulic oil cylinder; The forward and backward movement forward of stiffener plate unit thru machine main frame is driven with A.C. motor.
| Machine Model | J16, J20 , J28 |
| Width of Stiffener Panel Unit Base Plate | 1,000- 3,000 mm |
| Thickness of Stiffener Panel Unit Base Plate | 8- 16, 20/ 28 mm |
| Quantity of Straightening Unit | 3 groups |
| Top Assembled Downward Act Straightening Roller Transverse Stroke | 4,000 mm |
| Min. Interval between Top Assembled Downward Act Straightening Roller | 700 mm |
| Range of Interval between Angle Steels as Stiffeners | 225- 700 mm |
| Surface Height of Input and Output Conveyor Roller Table | 600 mm |
| Rated Pressure of Hydraulic System | 25 MPa |
| Max. Pressure of Single Straightening Unit | 30 Ton |
| Specification of Straightening Oil Cylinder | High Pressure Oil Cylinder D125/d70-S200 |
| Straightening Speed | 6,000 mm/min., constant |
| Up and Down Moving Stroke of Support Rollers | 40 mm, from 20mm beneath surface height of conveyor roller table, to 20mm above |
| Overall Dimension of Ribbed Plate Straightening Machine Main Frame | L 6,560mm x W 3,900mm x H 3,194mm |
| Machine Model | JF16 to JF24 |
| Applicable Width of Steel Plate | 1,500mm- 3,200mm, which is length of butt welding seam |
| Applicable Thickness of Steel Plate | 6mm- 16mm / 24mm |
| Straightening Speed | 6,000 mm/min., constant |
| Height of Infeed and Outfeed Conveyors Roller Tables | 800 mm |
| Quantity of Straightening Unit | 1 group, with 3 pieces of straightening rollers |
| Rated Pressure of Hydraulic System | 25 MPa |
| Specification of Straightening Oil Cylinder | D125/d70-S100 |
| Elevation Stroke of Front and Rear Support Rollers | 40 mm, the bottom height level is 10mm beneath mold |
| Overall Dimension of Plate Butt Welding Seam Straightening Machine Main Frame | L 5250mm x W 1610mm x H 3650mm |
Which often work together with Wuxi JACK J series Stiffened Panel Straightening Machine and JF models Steel Plate Butt Welding Seam Straightening Machine are:
1) XBJ series Large Size Long Stroke single or double heads Edge Milling Machine;
2) Special Design plate going type Heavy duty Edge Milling Machine;
3) RH series Large width steel Plate Edge Rounding Machine;
4) MP series Steel Plate Butt Joint Welding Machine;
5) Girder Longitudinal Welding Machine for BOX Beam;
6) Various types of Special Made Welding Machine;
As introduced at beginning of this page, the 2 types of Straightening Machines we discussed here are niche products for Shipbuilding and Port Machinery customers. In practical application field, there are some more often seen Steel Structure Straightening Machines:
1) H Beam Flange Straightening Machine, HYJ models motor drive medium duty, and YTJ models hydraulic drive heavy duty;
2) HJ models BOX H Beam Horizontal Press Straightening Machine, hydraulic drive;
3) ASM models Angle Steel Straightening Machine, motor drive;
Below are some machines listed above, produced by Wuxi JACK and delivered to customers in China and overseas markets, from March 2009 our company start up, to today May 2026 year: