Basic
Casting Design Rules It
is all to common to
design to suit the engineering department but
not the foundry, and the result may be failure or disappointment. From
the Foundryman's viewpoint, it is of first importance to design a
casting that can be made rather than one that may be perfect
engineering wise but which cannot be produced commercially and free
from structural weakness. Consultation between designer and
Foundryman will permit consideration of the foundry problems that are
likely to be encountered and will promote the making of a sound
casting. The time and cost of manufacture can also be considered at
this preliminary stage of casting design. Important questions that the
Foundryman can answer include: Type of pattern equipment needed, metal
shrinkage, molding method required, conditions necessary to make a
dependable casting, machine finish and dimensional limitations.
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In
designing adjoining sections, avoid acute angles. Replace all sharp
angles with radii and minimize heat stress concentration. Design all
sections as nearly uniform in thickness as possible. Avoid abrupt
sections change eliminate sharp corners at adjoining sections. Fillet
all sharp angles. Design ribs and brackets for maximum effectiveness avoid cross ribbing on both sides of a casting. Avoid complex ribbing. It simplifies molding procedure, assures more uniform solidification conditions and eliminates hot spots. Casting stresses and stress distribution favor omission of ribbing if the casting wall can be made of ample strength and stiffness itself. Avoid the sue of ribs meeting at an acute angle. Ribs meeting at acute angles cause molding difficulties, increase costs and increases the risk of defective castings.  Bosses, Lugs & Pads should not be used unless absolutely necessary. Bosses and Pads increase metal thickness, create hot spots and cause open grain or draws. Blend into casting by tapering or flattening the fillets. A continuous rib instead of a series of bosses permits shifting hole location. Thickness of Bosses & Pads should preferably be less than the thickness of the casting section they adjoin. Design all sections as nearly uniform in thickness as possible.  When the inside diameter of a cylinder is less than the wall thickness of the casting, it is better to cast solid. holes can be produced by cheaper and safer methods than by coring. |
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| Advantages of Permanent Molding Permanent Molds, made of steel or cast iron, are used for two major purposes. First, for products in continual production that must meet consistent tolerance requirements, and still have a competitive unit cost, and second, for short run products with critical tolerances. Obviously, Permanent Molding tooling is more expensive than Air-Set or conventional sand casts. But, advantages far outweigh negatives. In addition to maximum tolerance integrity, Permanent Molding is faster, enables single r multiple cavity molding, and produces castings that are easier to machine. Casting size is limited only to carrier capacity. Our standard carrier capacity is 22" x 34" but we can accommodate any size carrier a customer may need. Quality Air-Set Sand Casting Air-Set Sand Casting is the happy medium between Permanent Molding and conventional sand casting. Slightly more expensive than regular sand casting and less cosily than Permanent Mold tooling, rock-hard Air-Set Molds are perfect for limited run castings, that have complex cavity or special quality requirements. |
Heat Treating Ace Foundry has a modern electric furnace that can heat-treat castings up to 30" in diameter and five feet in length. Heat Treating is used to make castings harder stronger and more machinable. Furnace heat is thermostatically controlled and monitored. Quality Control Continual inspections performed throughout the production sequence account for Ace's reputation as a quality house. Seer item produced at Ace is inspected first by an operator at a production station, then by a roving quality control inspector, and if secondary services are required, by our Machine Shop Quality Control Inspector. A final inspection occurs prior to shipping. Every effort is mad to ship only castings that have passed our critical Quality Control inspections. |
Versatile Capacity Ace Foundry can cast virtually any side item in two major aluminum alloys: 319 and 356; the latter considered to be better adapted to Heat Treating and Machinability. Secondary services, via our machine shop or selected outside sources, include Permanent Mold fabricaton, Pattern Making, Turning, Milling, Center Grinding and Polishing. Complete product assembly on selected items is offered. Equipment To Do Your Job Ace Foundry has sfficient furnaace capacity for large or small production items. Only quality ingot aluminm is melted. No scrap metal is ever used at Ace. Permanent Mold carriers are hydraulically or pneumatically operated. Air-Set and conventional sand casting equipment are modern and well maintained. Machine Ahop facilities include late model equipment. Central Location Shipping, either by truck, rail or air, to all parts of the country is easy and economical due to Ace's strategic location in the "Heart of America" |