How to choose abrasive chips ?

The choice of & rsquo; equipment best suited to a mass finishing operation is an important point in our range of over 150 different models (vibrators, centrifuges different families…).

The choice of media is equally important, see more ; but the range of over 6500 products may seem difficult to understand.

They are chosen according to :

– The objective (deburring,fr, polishing , edges radiusing, brightening, sand blasted effect...) and parts material that define the abrasive power of the chips (more or less abrasive, or polishing) ; thus, for harder materials such as hardened steel or ceramics or zircones, one will choose a more powerful abrasive compared with more ductile materials such as brass, s & rsquo; Aluminum, Niobium or the & rsquo; Or.

– The size and morphology of the parts define the shape and dimensions of the chips

 

Main product code :

Shape codification :

– ACC : angle cut cylinder : Angle cut cylinder

– SCC : straight cut cylinder : Straight Cut Cylinder

– ACT : angle cut triangle : angled cut triangle

– SCT : straight cut triangle : straight cut triangle

– BALL : ball

– SCTS ou ACTS : angle or straight cut tristar

– P : pyramid

– WEDGE : wedge

– CONE : cone

Paraboloid : Paraboloid

Most common material codification (non-exhaustive list) :

Ceramic :

  • MGA : abrasive
  • FGA : low abrasive

Porcelain :

  • PW : medium grain
  • FPW : fine grain
  • FPRW : very fine grain

plastic :

  • TKS / TKX : very abrasive
  • TKV / TKG : abrasive medium
  • TKM / TKK : light abrasive
  • TKP : polishing

Metallic :

  • SS304 : stainless steel 304
  • SS316 : stainless steel 316
  • Copper : Copper

 

Some basic elements for choosing the right chips :

  • always choose the largest possible, allowing chips “to touch” all areas to be treated
  • more the chips are big, more they will have power ; they will thus have more effectiveness in eliminating some resistant burrs and reduce the cycle time
  • for deburring or polishing a hole of diameter 10, three strategies appear : solution A : we accept that the chips penetrate completely into the hole (with the risk of letting some chips inside the hole after the process and making necessary a final control) : the best choice may be cylinders diameter 8 ; an angle cut chip will facilitate the introduction of the chips in the hole ; we will ensure to eliminate the chips whose diameter approaches diameter 5, because it will block two chips (5+5=10); solution B : we refuse that the chips completely penetrate the hole : the best choice may be cylinders diameter 12 ; the tip linked to the angle cut will make easier the introduction of the chips inside the hole ; this solution presents some limits if we want to process an area inside the hole that is not very near the entrance of the hole ; solution C : same philosophy as the solution B, but using chips such as CONE TKS 12*12 (the tip of the cone will penetrate inside the hole without fully penetrate it) or ACTS MGA 15*15 (angle cut tristar)
  • do not forget to consider the separation stage between parts and chips at the end of the process ; If parts or chips are magnetic (see magnetic centrifuges), the problem is simple; on the other hand, dimensional separation will, with manual sievers for small quantities of parts, be sure vibrating screen , if you want a more industrial method; the dimensions of the media must be sufficiently different from those of the parts.
  • do not forget that the media has a wear rate due to their abrasiveness, but also to the power provided by the mass finishing equipment ; apart from porcelain chips (white ceramic), having chips that do not wear means that they work only very few, and instead of deburring and polishing parts, they generate hardening effects , often prjudicial to the quality of the surfaces
  • the choice of ceramic media or plastic media (polyester), can be quite tricky ; the main differences are due to their respective densities ; for ceramics, the density is generally 2.7 g/cm3, while that of plastic media is 1.5-1.8 g/cm3 ; thus, considering the same equipment, providing equivalent energy, ceramic media will allow greater material removal, better deburring, see a shorter cycle time ; On the other hand, for more ductile materials, such as Aluminum or Copper alloys, ceramic can mark surfaces, which would lead to favoring plastic media which are both lighter at equivalent volume and less hard ; but these rules are to be adapted according to the power and the capacity in liters of the equipment used…
  • these few basic elements will allow you to avoid the simplest mistakes ; feel free to contact us to get more complete advice ; the engineers and technicians of our laboratory will help you to solve your problems ; the laboratory is equipped with about 30 different equipment and with a range of more than 6500 different chips to help you to find the good solution or optimize your present process.