Cover for a component surface

Details Cover for a component surface Cover for a component surface

2000-04-13

2001-06-12

Shaw, Clifford C. (Department: 1725)

Metal fusion bonding

Including means to provide heat by friction between...

C228S212000

Reexamination Certificate

active

06244492

ABSTRACT:

FIELD OF THE INVENTION
The present invention relates to a cover for a component surface to provide protection against hot metal splashes.
BACKGROUND OF THE INVENTION
Covers for component surfaces, which are primarily used as protection during welding tasks where splashes are generated are well known. Such covers range from provisional solutions in the form of aluminum foil attached with aluminum adhesive tape to more elaborate solutions in the form of complex steel structures which are connected by means of screws to the components to be protected.
It is often the case that the surfaces of components near welding connections are already fine-machined or finished. If welding splashes hit such surfaces, then they can partially melt the component and they remain adhered to it. Removal of such cooled down components can be very labor-intensive, for example requiring removal by turning on the lathe, by milling or by grinding. Often, nicks, margins, bumps etc. remain which at least visually/aesthetically have a negative effect on the component, with the possible metallurgical effects being still more serious. The considerable local heat supply caused by a high-temperature weld splash of sizeable mass can lead to changes in the microstructure which negatively affect strength or fatigue strength, such as e.g. localized grain coarsening, embrittlement, hardening, softening, shrinkage-cavitation forming, cracking etc. By way of crack generation and crack growth, such flaws can eventually lead to failure of the component as a result of deformation or fracture. All kinds of surface coatings can also be locally damaged or destroyed by welding splashes. Therefore in many cases there is a requirement for providing a cover which safely prevents any welding splashes from contacting component surfaces.
Depending on the welding process employed, the energy content of welding splashes differs according to mass, temperature and speed, with rotary friction welding generating particularly harmful splashes as a result of its kinematics and energy density.
However, hot metal splashes occur not only during welding. Uncontrolled release of metal splashes can occur during production wherever a locally molten component material is generated with a high energy supply which is not always precisely controllable or where such splashes in a molten or liquid state can hit the surfaces of components or devices at considerable speed. Autogenous cutting as well as working with high-energy laser sources for the purpose of cutting, drilling and removing, are examples of such problematic process methods. Similarly, in the case of very substantial material removal, rotating grinding wheels or cutting-off wheels can generate critical metal splashes. All this confirms the requirement for protective covers for component surfaces.
SUMMARY OF THE INVENTION
In view of this situation, it is the object of the invention to provide a cover for a component surface as a protection against hot metal splashes, which is simple and economical to produce, reproducible, reliable and unproblematic in use as well as adequately robust and durable.
This object is met by a cover for a component surface that provides protection against hot metal splashes during the processing of the component or a nearby component by local generation of molten material. Such processing may include rotary friction welding. The cover prevents metal contact between the metal splashes and the component as well as critical local heat to the component. The cover comprises an elastic rubber plastic material which can be detachably connected to the component; a surface geometry faces the component and which is complementary to the geometry of the component so that the cover overlies the component; and, the cover has a uniform thickness that is matched to the energy content, including the kinetic energy, of the expected metal splashes to thereby provide adequate protection for the component.
In an embodiment, the cover comprises a silicone rubber that releases no fluid or fluid residue to the component surface.
In an embodiment, the cover is reusable.
In an embodiment, the cover has a thickness that is constant at every point at which the cover overlies the component surface.
In an embodiment, the cover is for use in the production of gas turbine rotors by rotary friction welding by combining disk-like components arranged coaxially one behind the other and which further comprise central apertures. The cover comprises a hub-like region which mateably engages the apertures of the component so as to absorb centrifugal forces.
In an embodiment, the cover comprises a hub-like region which blocks off access to the apertures of the component by means of a dimensionally rigid lid portion.
From the point of view of material, the cover comprises an elastic rubber material of adequate temperature stability which adheres to the component surface. If the adherence of the material of the cover is inadequate (which may apply in particular in the case of dynamic load by centrifugal forces/inertia forces), then in addition a suitable adhesive material may be added. It is important that the cover can be easily removed again from the component, preferably without destroying the cover.
Adhesion is improved or provided in that the surface geometry of the cover facing the component is precisely matched to, or complementary to, the component surface. This presumes that the component surface is also smooth, e.g. following fine-machining.
The puncture strength of the cover is matched by a minimal thickness to the maximum expected energy content of impacting metal splashes, i.e. their kinetic and thermal energy, i.e. it depends on the particular treatment process which generates the splashes. Thus by good matching, cover material can be saved, i.e. the weight and costs of the cover can be reduced.
Other objects and advantages of the invention will become apparent upon reading the following detailed description and appended claims, and upon reference to the accompanying drawing.


REFERENCES:
patent: 4162388 (1979-07-01), Heider
patent: 4362261 (1982-12-01), Cook, Jr.
patent: 5816859 (1998-10-01), Dubin et al.
patent: 5865364 (1999-02-01), Trask et al.
patent: 11297199 (1999-10-01), None

Affiliated with

Also associated with

Rating

Cover for a component surface does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Cover for a component surface, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Cover for a component surface will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2526223