No registration or passwords; no pop-up ads -- just aloha, fun, & answers.
(as an eBay Partner & Amazon Affiliate earns from qualifying purchases).
Home /
T.O.C.
Fun
FAQs
Good
Books
Ref.
Libr.
Advertise
 
Help
Wanted
Current
Q&A's
Site 🔍
Search
pub  Where the
world gathers for metal finishing
Q&As since 1989



-----

What should be the life of Aluminium Oxide (Alumina) used for shot blasting?




February 23, 2008

We use brown coloured Aluminium Oxide (Alumina) grits of virgin 40 grade for shot blasting of pressed components of thickness 0.4 mm to increase surface roughness. For this process, we use shot blasting machine with compressed air nozzle.

We face problem with wearing out of the alumina grits very often (within 5-6 hours). Due to this issue, productivity & consisitency of desired results is adversely affected. We would like to know--

1. What is the life of such grits?
2. What should be the frequency to replace them?
3. Are there any other materials or methods of shot blasting, which can replace these grits effectively to increase productivity?

Regards,

Sunil Shinde
Employee - Mumbai, Maharashtra, India



First of two simultaneous responses --

You are experiencing about a normal breakdown. Each pass thru the machine will make about half of the media one size smaller. White aluminum oxide costs a bit more, but is worth it when you consider the longer life and the less time spent on cleaning the machine.
For the longest wear, go to silicon carbide. It is not used that much in the USA anymore because our OSHA says that it can lead to silicosis if not controlled. The paperwork costs more than the controls.

James Watts
- Navarre, Florida
February 26, 2008



Second of two simultaneous responses --

Shot blasting, like mass finishing has a number of variables that effect the final results. The pressure you use will effect the life of the media, as will the angle to the surface will effect the life, the material you are working and the hardness or grade or the media (source) will effect the results. Normally, you can get more uniform results with a mass finishing system and longer life of the media.

tony kenton
AF Kenton
retired business owner - Hatboro, Pennsylvania
February 27, 2008


If your process allow you can opt for steel ball blasting. It will give you constant roughness and more life.

Rajesh dubey
- Kota, India
April 14, 2008


I think that his material is a bit thin for steel shot blast.

James Watts
- Navarre, Florida
April 15, 2008




(No "dead threads" here! If this page isn't currently on the Hotline your Q, A, or Comment will restore it)

Q, A, or Comment on THIS thread -or- Start a NEW Thread

Disclaimer: It's not possible to fully diagnose a finishing problem or the hazards of an operation via these pages. All information presented is for general reference and does not represent a professional opinion nor the policy of an author's employer. The internet is largely anonymous & unvetted; some names may be fictitious and some recommendations might be harmful.

If you are seeking a product or service related to metal finishing, please check these Directories:

 
Jobshops
Capital
Equipment
Chemicals &
Consumables
Consult'g, Train'g
& Software


About/Contact  -  Privacy Policy  -  ©1995-2024 finishing.com, Pine Beach, New Jersey, USA  -  about "affil links"