Posted by D. Novotny (220.127.116.11) on 17:54:12 18/02/06
In Reply to: Need to repair cylinder bore ID on alloy block posted by Erik Berg
Aluminum blocks have been welded quite successfully - drag and
endurance racers do it quite often - in the USA. However, the
process involves careful preheating, welding, thermal management
while welding and post weld stress relieving and re-heat treating
in some cases.
HOwever, depending on the severity of the weld/damage, it may cost more to weld and requalify the machine surfaces to straighten things out than the block is worth.
Moreover, if you've welded up what was a water jacket between the bores, localized overheating could be a lingering problem.
In the long run, you may be better off simply boring out the alloy, fitting in an aluminum tube/sleeve and welding the top and bottom. THis would preserve the cooling jacket integrity much better than than merely ladeling in a bunch of weld and dealing with same.
By the way and more importantly, lock ring failures (root cause of your problem) are caused by shutting down an overheated engine without benefit of cool off lap, too tight an endplay of the pin to lock rings and/or bent con rod.
The first two conditions cause the aluminum piston to shrink down faster over hot steel pin shoving out lock ring - latter condition is caused by poor inspection and/or hydraulic lock.
In some instances, improper assembly techiques can cause the lock rings to break but usually it is the items mentioned above...
Nature of Thermal Spray Coatings
Surface Engineering in a Nutshell
Surface Engineering Forum
Thermal Spray Gun Repair Service
Plasma Consumable Parts
Thermal Spray Powder Supplies
Thermal Spray Coatings on Carbon and Glass Fibre Reinforced Polymers
HVOF Coating of Paper Making Roll
Thermal Spray Processes:
Combustion Wire Thermal Spray Process
Combustion Powder Thermal Spray Process
Arc Wire Thermal Spray Process
Plasma Thermal Spray Process
HVOF Thermal Spray Process
HVAF Thermal Spray Process
Detonation Thermal Spray Process
Plasma Flame Theory
Cold Spray Coating Process
Wear and Use of Thermal Spray Coatings
Corrosion and Use of Thermal Spray Coatings
Glossary of Thermal Spray and Surface Engineering Terms
Image Directory for Thermal Spray Coatings
Plasma Gas Flow Information
Plasma Gas Flow Correction Calculator
Links to other interesting sites related to thermal spray and surface engineering
Periodic Table of the Elements
Calculators for Conversion between Units of Measurement
Surface Engineering Message Board Archive
Surface Engineering Message Board Archive Index
© Copyright Gordon England