lee webster | 25/07/2023 17:39:30 |
383 forum posts 71 photos | I thought I had better get acquainted with valve cages when I started to draw a small engine in Solidedge. I watched a video by Andrew Whale on the tube. The design was similar to how I thought it would be. But I also wondered if a steel plate with the valve seats could be fixed into an aluminium head. The silver part is the steel plate, one in place in the head, and one outside to show the shape. I drew the plate at 5mm thick, but I'm sure it could be thinner. The plate is held in place with two bolts/screws with sealant between head and plate. The cutaway pic shows how the plate would sit in a machined recess in the head. Is this viable? I feel that I have seen something like it somewhere. |
noel shelley | 25/07/2023 17:47:31 |
2308 forum posts 33 photos | Commercially it's done all the time, so yes. Sealing might be the only problem normally cast in or press fit then machine the valve seat. I would use 2 seperate seats. Noel. |
Dave S | 25/07/2023 18:20:11 |
433 forum posts 95 photos | For an alloy head and steel insert a shrink fit would be ok imo.
Dave |
lee webster | 25/07/2023 18:41:44 |
383 forum posts 71 photos | I have seen videos about valve seat inserts. They seem to involve heat and extreme cold. I thought a single plate would be a lot easier. |
old mart | 25/07/2023 19:06:31 |
4655 forum posts 304 photos | It might be easier to shrink fit and seal if it were circular, fitting into the bore of the head. Even better sealing if the outer diameter sealed with a head gasket. Normal practice is to make two circular cast iron seats which are shrink/press fitted into counterbored holes in the head and then the seats are finished in line with the valve guides. Edited By old mart on 25/07/2023 19:20:44 |
old mart | 25/07/2023 20:20:12 |
4655 forum posts 304 photos | I forgot to add, if two round seats are close together, the counterbores may be better overlapping and the seat inserts with flats where they contact. |
Please login to post a reply.
Want the latest issue of Model Engineer or Model Engineers' Workshop? Use our magazine locator links to find your nearest stockist!
Sign up to our newsletter and get a free digital issue.
You can unsubscribe at anytime. View our privacy policy at www.mortons.co.uk/privacy
You can contact us by phone, mail or email about the magazines including becoming a contributor, submitting reader's letters or making queries about articles. You can also get in touch about this website, advertising or other general issues.
Click THIS LINK for full contact details.
For subscription issues please see THIS LINK.