FABRICATION GUIDELINES
CUTTING
The HC 1600 series wear plate can be cut with plasma or carbon arc or fine abrasive saw blade methods only. Oxy fuel type cutting will not cut the hardface surface due to the high chrome content.
Typical plasma size is a minimum of 250 amps for cutting up to 1/2" thick plate. Thicker plate will need a larger power supply for cutting speed and to be slag free.
DC welding power is recommended for Carbon Arc cutting. At least 75 volts is recommended for up to 1/2" thick plate. Cutting the plate from the carbon steel side is recommended at all times. Grind back all surfaces to remove carbon slag from the base material.
A fine, abrasive saw blade can be used for cutting through the hardface surface. A ceramic silicon carbide wheel is recommended.
Cutting with a Plasma Arc
Cutting with a Carbon Arc
Cutting with a Saw Blade
BENDING
The HC 1600 series can be formed to most fabricated shapes such as pipes and cones by press brake or rolling methods. Because of the hardness of the alloy layer, there are some restrictions on what radius the plate can be pressed. The minimum bend radius is determined by the hardface thickness. The key is to create multiple bend lines. Typical minimum bend radius (BR) by thickness:
3/8" plate BR = 5"
1/2" plate BR = 6"
3/4" plate BR = 10"
1" plate BR = 18"
1 1/4" plate BR = 24"
1/2" plate can be pressed/ rolled to a minimum diameter of 12". For pyramid or pinch rolls, it is recommended that the top roll be protected with a sleeve. This prevents crushing the carbides in the hardface layer while forming.
When rolling with the hardfacing on the outside, a low carbon steel plate should be used to sandwich the hardfacing before rolling. The low carbon steel plate should be the same thickness for the base plate in order for stress to be distributed evenly across the section of the material being formed.
When rolling with weld joins, the alignment of weld joins to the direction of rolling is important to reduce the stress points of the weld joints. Always feed into the roll so the weld joins are perpendicular to the rollers (parallel to the
the direction of feed). By not using this method the plate can break across the weld join.
A hydraulic press brake is used for small diameter pipes, cones and square-to-round transitions. Forming can be done with a male and female combination of dies. Using a bullnose blade is most typical for pressing. Using a knife edge blade will result in crushing the carbide. Forming is typically done without preheating, or with just enough heat to take the chill out of the plate, no more than 300-450°F. The heat will not have an effect on the hardface surface.
Square-to-round transitions are the hardest to form because of the 90-degree corners on the square or
rectangular ends. Preheating those areas is needed for better results. The area being formed is usually heated to red hot, about 950°F. Entire plates can be pre-heated to 950°F or more.
Rolling
Weld Joins and Rolling
PRESSING
FIXING
The mild steel backing plate on the HC 1600 series allows it to be easily attached to other mild steel surfaces, including perimeter and plug welds, countersunk bolts and studs.
The simplest way of installing is to weld the carbon steel base to the existing steel structure. The common welding processes are Shield Metal Arc Welding (SMAW), Gas Metal Arc welding (GMAW), or Flux Cored Arc Welding (FCAW).
Since the base metal is carbon steel, any of the following electrodes can be used: E70 18 for SMAW, E70S-X for GMAW, E70T, or E71T for FCAW. For SMAW welding the minimum size power supply should be a 200 amp AC/DC unit; for GMAW welding, a 250 amp 100% duty cycle, constant voltage machine is always recommended.
The common way of welding is with a fillet weld. The most important factor is the size of the fillet weld. General practice
should be a minimum of 3mm between the top of the fillet weld and the hardface. The maximum fillet weld size can be calculated using the formula: Maximum Fillet Weld Size = Base Metal Thickness minus 3 mm
It is important the weld pool does not pick up chrome carbide from the hardface matrix as this will make the weld pool brittle and will lead to cracking.
The recommended spacing is approximately ¾" between adjacent sheets for best performance. This allows room for maximum fillet weld size. In applications, it is possible to reduce gaps by combining plug welds and butting up sheets.
For better results, minimum hole size of 1" is suggested every 12"-18" centers. Once the plug weld is cut, remove the slag and weld around 360°. The plug weld should be at least 2mm from the hardface layer and will need to be back filled to protect the weld from abrasion.
Studs can be easily welded to the mild steel base. Studs should be no smaller than 3/8” diameter. The number of studs will required engineering loading calculations. Generally, stud spacing of 12" is recommended. Follow the guidelines of the stud manufacture for best results. Also, torque the stud to manufactures specifications.
Another method of attaching onto a fixed or mobile plant is with bolts. Remember bolt heads and holes disrupt the aggregate flow over the alloy surface. The turbulence created around bolt holes accelerates wear and reduces the life expectancy of wear liners.
Perimeter Welds
Fillet Weld Size
Sheet Spacing
Plug Welds
Stud Welds
Bolts
JOINING
Wear Plate USA's HC 1600 series can be joined to itself or to other structural steels for fabrication. Keep in mind fabrication techniques are different from standard structural steels. Welding on the hardface is for wear protection only. All other welding should be done on the backing plate for standard application. None of Wear Plate USA's CCO plate is structural steel. Consult with your local welding dealer for more information.
We recommend using:
1) E7018 @ 90-11OA for SMAW.
2) E7OS-X @ 100-110A for GMAW.
The root pass must not melt through the "land" into the hardfaced layer. This can cause hardfacing
carbon to be picked up by the weld metal, resulting in a weld that is hard and brittle. For the fill
passes, use 4 mm (1 /8") or 5 mm (3/16") E7018 electrodes for SMAW welding (depending upon the plate thickness), or a standard E70S MIG wire for GMAW. Use the manufacturer's recommended amperage range for the electrode chosen.
It is recommended to leave about a 2mm gap between each of the sheets to assist in welding the alloy
overlay side. All sheets need to be dogged down hard against the work table the full length during welding. It is important for keeping the plate flat.
Before welding the alloy side, it is important to note that hardface welds are not structural. They are
simply a sealing weld for the joins to limit any potential gouging wear. No need to bevel the edges on the hardfacing side using the recommended Stoody welding hardfacing wire or rod. When welding the hardface of a polished plate, extra care should be taken to protect the polished finish. It is recommend to use a spatter template to cover the surface.
The HC 1600 series is designed to be used as a wear liner. It can be used structurally in the fabrication of
chutes, hoppers and bins with the correct engineering.
Joining the Mild Steel Side
Welding the Alloy Overlay (Hardfacing Side)
Structural Fabrication
POLISHING
Follow the disc 1 and disc 2 procedure for optimum results in fabrication and in-service polishing. The level ofpolish required depends largely on material properties and flow conditions. The HC 1600 series has the option of a pre-polished finished to suit the application in service. Buckets and liners carrying a "dead" load may require a higher level of initial polishing to improve material flow. A final, post-installation polish is necessary to remove any traces of weld spatter from the hardface surface or if the product has rusted before installation.
REPAIRING
The hardfaced surface can be hard to work with, and is easily damaged in fabrication. Cracks and chips can be repaired without compromising the wear performance of the liner. Follow the Stoody Guide for recommendations of hardface rod selection.
THERMAL EXPANSION JOINTS (CRACKS)
Small pre-existing stress expansion cracks are found in the hardface. These cracks are common in all hardfaced plates due to the manufacturing process. The mild steel and alloy layers cool at different rates, which can induce small stress cracks in the surface layer. These cracks do not affect the structural integrity or the performance of the wear life and should be left alone. Fabrication processes such as rolling and forming can sometimes induce cracks in the plate and/or chip the hardface surface. Cracks smaller than .040 should generally be left alone, but larger cracks or chips may be repaired.