For both practical and aesthetic applications, identification process for selecting the parting line is crucial. On the basis of the component design, we can identify the parting lines as simple or more complex. The tool engineer characteristically drives the location of the parting lines in reference to the input provide by the design engineer. There is always a transaction between cosmetic considerations, design considerations, and mold ability of the component. However, the close examination of the draft angles and shutoff angles sections helps in identifying the parting line on component.


To select a suitable parting direction is the first and foremost step in the design of parting line. To identify the parting direction, the first lot of alternatives is provided by the centerlines of the minimal bounding box of the casting. Other lots of alternatives are produced by the direction of normal to large faces in the casting. The criteria for selecting the most suitable parting direction include (in decreasing order):

• Minimized number of external and internal undercuts.
• Shortest total draw distance including both halves.
• Minimize draft allowance also known as volume increment.

By using an adjoining shaped code, an undercut feature is obtained. This requires higher costs of special raw materials, supplementary tooling and lesser efficiency. The number and volume of cores must be minimized by selecting an appropriate parting direction.

External undercuts are produced voluntarily during the molding process. The undercut feature in the designing of the mold reduces the necessity and cost related to removing of the burr on the stamping.

Effectively, an amplified level of complexity can also be made available in the component without affecting its overall price, while at the same time the design of the component reduces the requirement for a further deburring process on the stamping. While designing components are produced, consideration of product assembly requirements is an important aspect.

By injection molding under the certain conditions, internal undercuts are probable. Internal undercuts are designed and can be readily produced, with a mechanical or hydraulic actuated slide. Components that are very small and easily collapsible are often impractical and some times impossible to produce.

The parting line is required to intersect the estimated borderline of the casting when viewed alongside the draw direction. To accomplish the parting line, the corners of the castings are projected perpendicular to the plane of the parting direction.

Also, the outermost boundary's perimeter is considered overlooking the innermost sections of the projected corners. This is anticipated back to the casting and the respective landing points are estimated.

Then these landing points are joined to each other in the same order to form parting line. Multiple substitutes of parting lines are required to be figured out in case of multiple landing points. These alternatives of parting lines are capable of generating flat, stepped or complex parting lines in respect to the geometry and shape of the components.