What is metal spinning

What is metal spinning

Metal spinning is a metal forming process that can make a circular metal sheet deform different shape of revolving body .the spinning mold and clamp provide the clamping force and take the sheet to spin .When the spinning roller touch and press the sheet according to the spinning path, the sheet will produce plastic deformation from the point to the line follow the spinning path .

Spinning deformation force on the sheet

metal spinning work principle instruction

Clamping force of tailstock
outputed by hydraulic cylinder of tail stock .the friction force can make the sheet turn follow the spindle .
Turning force of spindle
outputed by spinndle motor and taking metal sheet turning.
Pressing and pulled force of roller
outputed by X-axis and Z-axis motor and stopping touching poisition (roller and metal sheet ) move follow the spindle spinnning direction ,the touching poisiton will deform according to the spinning path and the spindle spinning opposite direction.

Axial and radial deformation

Axial and radial deformation

● Axial deformation : Axial of metal sheet will be longer and thinner after pulling of spin roller .

● Radial deformation : Radial of metal sheet will be smaller after pressing  of spin roller . the spinning roller move path is a helical line.

Shear and conventional spinning

● Shear spinning : metal sheet is pressed by roller and mold ,it make sheet shear deform. it is the position that roller press the sheet touch the mold together.

● Conventional spinning : metal sheet is pressed and pulled by roller only .it make sheet stretch and deform.

Hand spinning and CNC metal spinning >>

CNC metal spinning develop and research based on hand spinning ,Hand spinning control spinning roller to move by hand ,CNC  metal spinning control the spinning roller to move by CNC ( computer numerical control ).

CNC metal spinning can output stronger spinning force to form the thicker and harder metal ,the accuracy is higher than hand spinning .

Materials >>

Main bank metal classify tube and sheet , the other blank shell made by Deep drawing and casting  can be used in metal spinning as well .

Metal spinning is divided into tube spinning and sheet spinning according to the blank metal tube and sheet .

Material shape 

metal spinning blank material round sheet and cylinder tube

Sheet performance

Sheet is classified cold rolling sheet and hot rolling sheet.

The hardness and tensile strength of cold rolling sheet is higher than hot rolling sheet .the thickness cold rolling sheet is less than 5mm, if the thickness is bigger than 5mm, it is the hot rolling sheet .

Cold rolling have better ductility ,because hot rolling have more has porosity and trachoma .

Tube  performance 

Sheet is classified seamless tube and welding tube .

Thick tube is seamless tube ,the thin tube is welding tube .

 Stainless steel welding tube should be welded by SU304 DDQ, otherwise tube will break after spinning .


Sheet : 1m*2m,1.24m*2.44m,1.5m*3.0m

Tube : It needs to make mold to custom, the stainless steel tube must be DDQ standard (can be deep drawing ).

Common blank metal types 

Aluminum : 1060 /1070/ 1100/3003 / 5052 / 5251 /5083/ 6061

Titanium: TA1   Carbon Steel : SPCC / DC04 / Q235/ Q345    

Silver : IC-Ag99.99   Copper : C10 100 / T1

Stainless steel : 201 / 304 / 316 / 310 

Special blank metal types

Hardox 400   GH3044   SUS310   SUS630   Incone 718   TC4

Aluminum 2024/2A12/7075    AL 5A06   AL  7075   Titanium Ta1

Heating spinning and cold spinning

Heating spinning and cold spinning

cold spinning can make the soft (common metal )and thin metal sheet ,but heating spinning need to make hard (special metal ) and thick metal sheet by heating .heating ways have High - frequency heating and gas heating . Heating can reduce the hardness and tensile strength of special metal .

Metal spinning shape

Metal spinning shape

Metal spinning form tube and sheet to different shape ,such as venturi ,sphere ,cylinder ,cone ,trumpet ,flanging ,compare to deep drawing ,the necking and tube spinning can make the shell into more shape base on the following of shape .

Metal spinning thinning rate

Blank sheet will be thinning after metal spinning ,comon conventional spinning thinning rate is 10-20%,the depth of cylinder  is deeper ,the thinning rate is bigger .cone is shearing spinning ,the actual thickerness after spinning =sin Aº*blank thickness ,  tube necking will increase the thickness and expanding will reduce the thickness , cylinder shearing thinning rate is biggest .

Spun products properties

The strength and hardness of the spinning products are more stronger than other forming processes. The spinning cold extrusion process produces grain refinement and increases the hardness and strength of the product. Under the conditions of the same wall thickness, the metal spun products have better strength and hardness . This is the reason why aerospace and aircraft thin-wall rotary parts are spun. On the other hand, the spun products have a more stable and high performance in harsh and high-temperature working environments, under the same conditions, the accuracy and rigidity of the spun parts  are more excellent than other forming processes after continuous temperature rise and  bearing force  .

● Strong strength

● Good accuracy

● High-temperature performance

● Smooth surface 

CNC metal spining machines >>

CNC metal spining machines

With the development  of  cnc metal spinning machine tools , hand spinning is reduced and replaced by CNC, CNC metal spinning machine can output stronger spinning force and control the accuracy easily .the basic machine structure is similar with CNC turning . the difference is CNC metal spinning machine needs stronger process force and quicker feed speed than CNC turning ,so the motor ,guide rail and lead screw of CNC metal spinning machine is bigger .

CNC metal spinning machine have single roller and double roller machine ,double roller works more balance than single roller ,thinning rate of double roller is bigger than single roller as the pull and press force of double roller is biger.

CNC metal spining machines parameter

Spindle motor power :  spindle force 

Axis motor power and  leading screw specification : spinning roller force 

Hydraulic pressure of tailstock cylinder :  friction force of sheet

Harder ,thicker and bigger diameter needs heavy duty metal spinning machines ,it needs stronger spindle force and spinning roller force  to deform.

Softer,thinner and little diameter needs light duty metal spinning machine ,it works more fast with a high spindle speed and feed speed .

CNC spining path and program >>

● Spindle speed :  spindle speed is higher ,the thinning rate is less .the surface is more smooth .

● Feed speed : the feed speed is high ,the thinning rate is less ,the surface is worse .

● The radius of roller : the radius is bigger ,the thinning rate is less ,but the edge of sheet is wrinkling in the spinning .the radius is little ,the thinning rate is  bigger ,the bottom (near the mold surface )of the sheet is easy to break in the spinning.

● CNC spinning path : this is most important factor in the spinning ,right CNC spinning path can form the sheet with a good surface and precision .

CNC spinning tool

● CNC spinning roller >> : a tool to deform the metal sheet or tube .

● Metal spinning roller post : a tool to assemble the roller to the machine .

● CNC turning parting tool : a tool use to turning the edge after finishing metal spinning .

● Air pressure device : It help metal spinning product to demold .

● Blank shelf : it is used to control and put on the blank sheet in the center of spindle .

● Heating equipment : high frequency heating equipment and gas heating tanks .

● Tube spinning fixture>> : it is used in tube spinning to hold the tube tightly .

Metal spinning advantage

CNC metal spinning mold is cheaper and less than deep drawing, aluminum extrusion and other metal forming . the mold manufacturing period is short, it is easily to adjust the mold size by CNC turning . Metal spinning make grain refine ,the strength and hardness of metal spinning products are improved ,these advantages make metal spinning are best choice in the military and aerospace industry. the advantage is obvious in the small-batch production , large size of metal spinning products and complex shape .

The disadvantage is metal spinning production efficiency is not high .

Metal spinning application >>

Metal spinning is wide applied in different industries ,metal spinning can process complex shape ,thicker and bigger blank sheet ,high accuracy and strength ,these advantages make metal spinning play a irreplaceable role in the manufacturing .

● Tensile strength : these components need to bear force such as oxygen tanks ,pressure container and bottle.

● Complex shape forming capacity : it applied in decoration ,such as lampshade ,table base .

● Large dimension : it applied in industrial fan ,industrial funnel ,firebowl .

● Special metal : the special metal material are working in a rugged environment such as high temperature , vibration, high speed and bearing the force .special metal and heating metal spinning is better choice for military and aerospace industries .