Initial enquiry sketch for node castings

Customer sends Goodwin an outline sketch or drawing of the shape of the casting they need with the main critical parameters in terms of size, section thickness and integrity that they need.

CAD model of the node produced from the thermal analysis

Goodwin generates a detailed drawing ensuring the critical parameters are adhered to but adding features essential to the casting process such as fillets and radii.

Thermal analysis carried out by the foundry to determine the optimum cast shape

Goodwin carries out a computer casting solidification simulation and then engineers a casting feeding system that will ensure a casting with appropriate integrity for the intended duty specified by the customer. When a casting solidifies from its molten state at 1450°C, about 7% internal volume shrinkage occurs and this will end up as shrinkage cavities unless the foundry puts a suitable feeding system on the casting.

Final casting drawings produced from approved model

The drawing is then returned to the customer, this illustrates the final shape, fully dimensioned with the tolerances that can be achieved both for cast dimensions and also for machined dimensions. In some instances Goodwin will offer a modified shape that would give rise to a better casting be it integrity or lower cost of manufacture for the customer to approve or otherwise. This stage of the interaction process is very important and allows for the customer to obtain the casting that suits his needs best at the lowest price.

Non-destructive testing being carried out

It is at this stage that, if the customer is uncertain as to the level of testing on the castings that he needs, Goodwin will propose to the customer for his approval a non destructive test (NDT) program that would seem most appropriate to the duty indicated by the client.

For example: radiography or ultrasonic inspection together with crack detection on the sample, or perhaps, on the sample and 10% of subsequent castings or on the sample and on all castings subsequently poured. Also discussed is the amount of coverage on the casting of the NDT.

Model made 'pre-order' to investigate shape

It is at this stage that the client is in a position to place an order if he so wishes. As can be seen by this stage Goodwin has already carried out a lot of work, but it is our historic experience that although we sometimes do not win orders where we have spent a considerable amount of time and money in ensuring we can make the castings being asked for, it positions us to deliver successfully to specification on schedule. It is this up front work that differentiates Goodwin Steel Castings from most other foundries in the world of similar capability and it is this work that has allowed us to have an unblemished delivery record on all the major projects we have supplied on in the past 15 years. Too many foundries work out a casting price based on weight and then having taken an order end up being unable to deliver to specification and to schedule.

Final pattern for customer review

Order processing on computer and commencement of pattern manufacture. On certain contracts the customer or his client may wish to review the pattern prior to the first casting being made to confirm the foundry’s interpretation of shape and to satisfy any design or interface concerns.

Manufacturing method undergoing final review

Submission by the foundry to the customer, the agreed manufacturing and test plan for final approval should such be a feature of the contract.

Molten metal prepared for casting

Produce the first mould to the casting method which was developed in the computer and then cast the first casting.

Castings undergoing shotblasting

Stage 10 Process the first casting including riser removal, heat treatment, dressing and shot blasting.

Dimensional inspection of first-off casting

Dimensionally and visually inspect the first casting to confirm adherence to drawing and specification.

Hardness testing of casting

Carry out the contractual mechanical testing using a keel block, that was cast at the same time as the casting, to confirm the mechanical properties.

Surface inspection being carried out

Carry out the contractual non destructive testing such as Radiography, Ultra sonic, Magnetic Particle and or dye penetrant testing to confirm the casting conforms to the agreed contractual casting integrity. If necessary modify foundry casting method to improve the casting quality.

Architectural casting being prepared for shipping

Manufacture and ship the remainder of castings ordered to contractual specification.