Transfer Die Stamping: The Ultimate Guide
Transfer die stamping is one of the methods used to stamp metal parts for use in different industries. In this guide you will find all information you are looking for about transfer die stamping process – let’s dive right in.
What Is Transfer Die Stamping?
Transfer die stamping is a metal work process similar to progressive die but uses individual metal parts to create the desired profile. This process is automated, enabling movement of the part from one station to another using ‘fingers’ until all operations are completed. Transfer die stamping can range from a single die to multiple dies. Several machines are sometimes arranged in a row to form a production line.
Advantages Of Transfer Die Stamping
This process allows the incorporation of other operations such as cut-outs, holes, knurls, etc., making other additional features possible.
Transfer die stamping uses individual parts separated from base metal, making facilitating them easier and faster.
Transfer die stamping has been automated, thus moving parts from station to station faster than manual movement.
The fact that parts are free from base metals makes this process ideal for large parts production compared to other stamping methods.
How To Choose Transfer Die Stamping
Transfer die stamping is ideal for large parts production, while a progressive die is best suited for small parts.
Some features can only be achieved by either progressive or transfer die stamping. For instance, cut-outs, ribs, knurls, etc., can be achieved during the transfer die stamping primary process, not progressive die. It is economical to use transfer die stamping to achieve such features.
Quality Of Stamped Parts
Transfer die stamping is automated thus very efficient and also allows additional operations like knurl, rib, etc. which produces quality parts.
Include information such as; strokes per minute (fixed/variable), stroke length, type of drive, shut height, window size, etc.
Include; pitch length (max/min), make, clamp length (min/max), lift height (min/max), speed/control limitations, etc.
Choosing Materials For Transfer Die Stamping
When choosing metals for transfer die stamping, factors like ductility, tensile strength, mechanical characteristics, etc. are put into considerations.
Both ferrous and non-ferrous metals are used; ferrous containing iron thus susceptible to rust and are magnetic and non-ferrous being neither.
Aluminium metal is a nonferrous metal made from raw aluminium and is known for its strength, light weight and non-corrosion. It is usually alloyed with other metals to enhance its properties. Aluminium has great formidability thus can easily be shaped into any desired profile.
Stainless steel is a ferrous metal that contains iron. It also has chromium and nickel components whose amount determine the steel grade hence are applied differently. For example, stainless steel 316 is mostly applicable in marine, while steel 404 in chemical and food processing.
Also a nonferrous metal that is very ductile thus can be manipulated into different shapes without breaking. It is resistant to rust thus is commonly used in medical, food and beverage industries. Copper can be used in its pure form, however, its alloys are preferred as they have improved strength and durability.
Steel is mainly composed of carbon which contributes to its hardness. The higher the carbon level, the harder the metal thus its excellent durability. Chromium and nickel are alloys of steel which are preferred as they are resistance to corrosion thus prolonging steel lifespan.
Brass metal is an alloy of copper made up of zinc and copper. The levels of the two determine its grade and ductility. Brass is known for its aesthetic value due to the smooth and sleek surface, good conductivity and rust resistance. Zinc levels in brass determine the hardness and grade C26000 is popular due to its resistance to corrosion.
These category consists of various metals which are engineered to withstand harsh conditions such as extreme temperatures and corrosion. They do so without corroding, degrading or becoming brittle. Example of speciality metals include; titanium and nickel based alloys. These metals are known for their durability, resistance to impact and improvement of base metal strength.
Transfer Die Stamping Process
This stamping process can involve single die, multiple dies or production line. The work-piece to be stamped is fed into the first station where the blank is cut off from the metal strip.
This part is then moved automatically using ‘transfer fingers’ where a specific procedure is performed. Automation has lowered interference during operations and enabled the smooth running in a single press.
The part is moved through all the stations till completion of the process. This happens at the same time for all the parts. Additional features such as hole piercing, knurls, chamfering and threading can be incorporated into the primary process.
Transfer die stamping can be applied for use in the manufacture of tubes, shells, frames and structural components among others.
Progressive Die Stamping Vs Transfer Die Stamping
Progressive die stamping uses a part when still attached to the metal strip whereas transfer die uses part separated from strip. Work-piece remain attached to the metal strip and only separates at the end, while transfer die separates work-piece in the beginning.
Progressive die stamping, uses multiple stations within one machine while transfer die uses either single die, multiple or production line. In both, the parts move from one station to another for the procedures to be completed.
Progressive die stamping is ideal for production of small parts with strict tolerance in large volume. Transfer die stamping is used for large parts productions such as frames.
Transfer die stamping can include complex features like ribs, knurls, cut-outs. etc. in its primary production for additional design features. This is not possible with progressive die stamping thus requiring secondary production process.
Since only one machine operates in progressive die stamping, labour cost is reduced. Transfer die stamping has higher labour cost because in some cases a production line maybe set up.
Progressive die stamping is generally costly because secondary operations are required; transfer die stamping is versatile and incorporate other operations. Both progressive die stamping and transfer die stamping are automated hence reducing interference in between production. They both utilize similar metal materials such as ferrous and non-ferrous metals, e.g. stainless steel and aluminium respectively.
Compound Die Stamping Vs Transfer Die Stamping
Compound die stamping utilizes single stroke to execute multiple cuts, punches and bends, while in transfer die stamping applies single press. Compound die stamping uses a single die to enhance repeatability, transfer die stamping uses single die, multiple dies or production line.
In compound die stamping the part manufactured is flatter whereas transfer die stamping produces different shapes as desired. It is faster to produce small parts in compound die stamping due to simultaneous operations but not for large parts. The same applies to transfer die stamping.
Transfer fingers are not required in compound die stamping because there is not station but a single die. Transfer die stamping is fitted with transfer fingers as part of automation process to facilitate smooth movement. Compound die stamping is cost effective because the tooling is cheap and faster to build unlike transfer die stamping.
Simpler designs are manufactured by compound die stamping while intricate designs are ideal for transfer die stamping.
Ways Of Loading Material In Transfer Die Stamping
Uses coil handling system and a window wide enough to allow for coil passage. It is ideal for square and rectangular shaped blanks to avoid material wastage. A carries is required in progressive die stamping for efficient material use. Transfer die stamping is ideal when loading expensive materials.
combines coil-fed method in progressive die stamping for blanking and transfer die stamping for the remaining operations. It is common with in-die mechanical, hydraulic or pneumatic transfer than in-press transfer method. It does not require blank destacker.
Allows for efficient material use since blanks are produces from coil in a faster way. It eliminates some transfer stations thus can accommodate some transfer in smaller fits.
Forming Dies Vs Cutting Dies In Transfer Die Stamping
Some operations include:
Bending: Creates L, U or V shape by applying stress on yield level below the tensile strength on a single axis.
Flanging: Bends the metal along a curved axis to produce either a curve or corner through tension or compression process.
Drawing: Drawing displaces work-piece surface with another shape of similar surface area.
Stretching: An act of increasing surface area of a work-piece through tension and thinning.
Coining: Coining results into pattern creation by subjecting the work-piece under high pressure and reducing its thickness.
Ironing: Unlike coining, ironing reduces wall thickness along the metal depth.
Some of the operations include:
Shearing: Shearing is cutting of a metal on a straight line through pressure application commonly used in parallel cuts.
Blanking: This is removal of a portion of a metal strip along special contour or shape and using the cut out piece.
Trimming: Cutting out of the edges to form desired profile.
Notching: Cut process that aids with bending or cornering process by incising a V-shapes cut on the outside of the work-piece.
Piercing: Similar to blanking only that the removed part forms a scrap and the remaining piece a work-piece.
Disadvantages Of Transfer Die Stamping
The general cost of planning and design of transfer die stamping is high as well as time consuming.
The tooling is complex and requires technical monitoring, testing and adjustments to ensure quality production.
It is hard to check the condition of the die during production cycle due to high speed. This therefore forces installation of protection sensors.
The two-axis system that controls work-piece movement from die to die slows down production process.
De-stacking mechanism is necessary to control blank flow and time their insertion.
People Also Ask:
Manufacture of parts using stamping method still attached to the metal strips and with tight tolerance.
Progressive die stamping
Compound die stamping
Transfer die stamping
Compound die is less costly than progressive die stamping because it is easier and cheaper to set up tooling.
Compound die combines multiple cuts, punches, etc. in one stroke while this happens in different station in progressive die stamping.
The space between punch cutting edge and the die button cutting edge and is determined by the thickness of the material.
Die secures the part and does stretching and blanking operations. Punch on the other hand stretches, bends or blanks parts.
You can use transfer die stamping to make a range of parts and components in medical, automotive, food processing, agriculture, electronics, aerospace, and retail industries.
The parts may vary from small components to large sections. They may include frames, tubes, casing, or shells, just to mention a few.