You must to know material specification for tube machined project

Case Study: It is very important to know material specification for tube machined project.

We get a order of tube machined parts from a Canadian customer in October,big diameter with 65" long,C1020 material, OD 8" x 0.75" wall, it's difficult to buy this inch tube in China,unless make mold specially,but the MOQ is 10T.

The offer we provided to customer is based on OD8 x0.78" with out machining inner diameter.When we book the raw material HRS tube,we found the surface of inner diameter is very rough,with rusty black skin,it is not possible to used for precision machining parts if the inner diameter without machining.

We have difficulty now,it is easy to machining OD ,but we don't have a bility to machining ID for so long tube.Due to complete this project for customer,we began to search the tube with smooth inner surface.It is called grinding tube,rough OD and smooth ID.Material cost twice as much as HRS tube.The inner diameter is bigger 0.08" than HRS tube.After confirmation of the dimensions changing with customer,we start working on it.

We found a new problem in the process,since the thickness of grind tube is uneven,the difference is about 0.078",so there is somewhere of outer diameter not processed,if increase the tool feed,the smaller diameter will be obtained and the wall thickness will be thinner than the tolerance requirement of the drawing.Communicate with customer again,we get instruction is that make sure the dimensions and ignore the appearance.

In Turning Process

One month, we finally finished this project, although no profit, but we completed the order.In business, honesty is more valuable than money.Through this project, we have deeply realized that the earlier quotation work needs to be more detailed,especially for tube machined parts,we should know more details of raw material,such as the tube specification,surface roughness of tube,dimensions tolerance.

If the customer can consider the existing specifications of the market materials in the design,Design reasonable size according to the application demand of the product,Will reduce material cost and processing cost.

How to reduce the distortion of Delrin machined parts during processing?

POM/ Delrin. Thermoplastic crystalline polymer,it is known as 'super steel',with high mechanical strength and rigidity,strong impact resistance,used for widely temperature range (-40℃~120℃).

At present,the Delrin as lower cost of plastic,It is replacing some of the markets that have traditionally been dominated by metals.For examples,alternative zinc alloy, brass, aluminum and steel parts.Has been widely used in electronic electrical, mechanical, instrument,daily light industry, automobile, building materials, agriculture and other fields.

But it's not easy to process.The delrin machined parts is easy to deform during processing. SYM precision team always machining the delrin machined parts slowly,and comply below steps.

1. Annealing the raw material first.

2. Cutting standard material with more machining allowance (10mm~20mm).

3. Try to process more steps,take a long time (12~ 24hours)to let the delrin part cool down during every steps.

4. use as little force as possible to hold it during machining,or use glue instead of clamps to fix the product during process.

5. Use high speed steel tool instead alloy steel tool,because the high speed steel tool is very sharp,the heat produced is small during the cutting process.

6. Keep small cutting output during the process.


Even we did all above,there still exist small distortion for Delrin machined parts for its character,so if the dimensions within 0.05mm(0.002") tolerance of your machined parts,please consider other material,Aluminium Alloy or Steel.

7 kinds of clamping method of turning eccentric parts

In mechanical transmission, the rotary motion into reciprocating linear motion or linear motion into rotary motion, usually with an eccentric shaft or crankshaft to complete.Eccentric shaft that is parallel to the axis of the parts between the cylindrical outer and without overlap. The method of turning eccentric parts,according to different quantity,shape and precision of the machined parts.

Turning + Grinding Parts

There are 7 kinds of clamping method of turning eccentric parts.

1. With four-jaw chuck turning 

This method is suitable for processing eccentricity smaller, less precision, shorter and smaller quantity of eccentric parts.

2.With three-jaw self centering chuck turning

This method is suitable for mass production,shorter and smaller eccentricity,less precise eccentric parts. Spacer should be added in a claw of three-jaw self-centering chuck.

3.With double chuck turning

This method is suitable for processing short length,eccentricity is small,a large quantity of eccentric parts. Should adjust the eccentricity before processing.

4. With faceplate turning 

This method is suitable for the shorter length,the larger eccentricity,less precise eccentric parts.Before machining eccentric hole,the firs processing is turning out diameter and two ends surface,and then machining the eccentric hole.

5.With eccentric chuck turning

This method is suitable for processing short axis,the disc,tube with high precision eccentric parts.

6.With two top turning eccentric parts

This method is suitable for processing longer eccentric parts,before machining the parts,should draw the center point and eccentric point on both sides of the parts,and then turning.

7. With special fixture turning eccentric parts

This method is suitable for high-precision machining, and larger quantities of eccentric parts. Before processing should be processed from the corresponding eccentric shaft or eccentric according to the eccentricity of the part, and then clamping the part on eccentric shaft for turning.

Please Contact Us for Insistent Offer of your machining needs.

What is grinding process?

Precision Grinding Machining Parts

Grinding process is also known as grinding machining.

Grinding is machining the surface of metal parts by grinding wheel,oil stone and abrasive.The machine tool that uses grinding wheel is usually called grinding machine,the machine tool that uses oil stone and abrasive is called precise grinding machine.

The grinding wheel is a cutting tool with a lot of small and extremely hard abrasive particles.From its cutting action,each of the fine grinding granules on the surface of grinding wheel, the effect is equal to a subtle blade.grinding machining just like countless subtle blade cut at the same time.

In grinding process,blunt the edges of the grinding grain,since the effect of cutting force,It often breaks or falls off to reveal a new sharp sharpen,This kind of
The phenomenon is called self -sharpness of grinding wheel.

The abrasive grinding process produces a lot of heat,So we need to cool down with a lot of flowing cooling water.

The range of grinding is very wide,almost any surface can be machined with grinding,such as inner and outer cylinder,Internal and external cone,kinds of plane,the screw thread,gear, spline, forming surface.Further more,it is hard to process hard materials such as hardened steel and hard alloy.

SYM Grinding Team

Due to the multiple blade and self-sharpness of  grinding wheel, high cutting speed and The grinding machine has high precision,the precision and surface finish of metal parts are high after grinding,The average grinding precision reaches grade 1-2, the roughness can meet Ra0.4-Ra0.8, for precise grinding parts,the surface roughness can meet Ra0.05.

At present, the grinding process is generally used as the finishing process of parts surface.However, it can also be used for rough processing of preprocessing and cleaning works.

3 point you must to know for design complex CNC Machined Parts

Complex parts are the most common processing products in CNC machining.In the process of processing complex parts,Its processing route will be covered.
Including selection processing methods, division of processing stage, division process, processing sequence arrangement and determination of the processing route and so on.

complex CNC machined parts

1.Determination of parts blank

According to the parts process design, the selection of the blank is to determine the type of the blank, the manufacturing method and the size of the blank after determining the residual amount.

The material is steel. According to technical requirements,The parts are required to be deburred,that is to ask for the appearance of clean and beautiful.According to the structural shape of the parts overall dimensions,can select forging.

It is necessary to select the steel that has been processed, because it has a high hardness and is suitable for cutting.

2.Determination of locating datum of complex parts

When selecting coarse benchmarks for processing, the key consideration is how to ensure that there is sufficient allowance for each machining surface.Make the size and the position of machined surface and unmachined surface meet to prints.Therefore, the rough datum selects the blank plane.According to the processing of the concave, the machining requirements of the hole,select the base plate to location datum.

SYM CNC Machining Shop

3.Machine selection

Different types of parts should be machined on different CNC machines,by different CNC machining process, and machine tools should be selected according to the design of the parts.

1) The CNC lathe is suitable for machining complex shaft parts and the mold inner cavity formed by the rotating complex curve.

2) CNC vertical machining center are suitable for processing box, box cover, flat CAM, shape complex plane or the internal and external cavity of the mould.

3) The CNC horizontal machining center is suitable for processing all kinds of complicated box parts, pump body, body, shell and so on.Multi - coordinate horizontal machining center can also be used to process various complex curves, surfaces, impeller, mould and so on.