Top 50 Manufacturing Industrial Engineer Interview Questions You Must Prepare 24.May.2024

It is the maximum force that the clamping system can exert on the mold or it is the maximum force by which the mold halves can be closed together. It is given in ton or kilo Newton.

  • Cold defects 
  • Hot defects
  • Miscellaneous defects

It is a custom build tool in which we converts plastic raw material into finished product.

The function of this gate is identical to that of a diaphragm gate. This type of gate is used for tabular type moldings when more than one impression is required in a simple two mold.

Automatic degating with less mark also called as sub surface gate or submarine gate.

  • Flash mold
  • Fully positive mold
  • Semi positive mold
  • Landed positive mold

Shrinkage 0.7-1.5%. It is tough and high rigid. Examples are light duty gears, sprockets, bearings etc.

Cycle time Tc=m*3600/P

 Where ,Tc =minimum cycle time obtainable 

 M=mass of the shot 

P=plasticizing capacity of the machine with the particular polymer being molded (kg/h)

In this, runner kept hot to keep the molten metal into fluid state also called runner less mold. In this, runner contained in a plate of its own runner section of the mold is not opened during molding cycle.

  • Increase of material temperature.
  • Increase of mold temperature.
  • Increase in wall thickness.
  • Low injection pressure.

Alkyds, epoxies, pf, mf, urea, polyester

It is the amount of material that can be processed by the machine per hour. It is expressed in kg/h.

It is the maximum pressure by which the material is injected through the nozzle. It is given in kg/cm2.

This is a long rectangular type edge gate and it is used for large thin walled components to assist in the production of war page free products.

Leakage of plastic material through the nozzle in between shots.

  • External with mold surface e.g. Polyvinyl alcohol 
  • Internal with resins eg. Silicon oil

Maximum volume material injected by the screw during one cycle of operation.

This is the simplest to install. It is easy to connect to the fixed or moving half. The medium of actuation is compressed air.

A stripper plate mold consists of a fixed plate, a moving mold plate and a stripper plate. There are two day light when opened. This is called double daylight stripper plate mold.

Shrinkage (FLEXI 1.5-3%,RIGID 0.2-0.4%). It is rigid and not very tough and very low cost. Example - Pipes fittings.

Connecting member between impression and runner.

Finger cam length =(M/Sin Q) +(2c) l Sin 2Q


 M= split movement

 Q=angle of finger cam 

 L=working length 

 C =clearance

Any recess or projection on the outside surface of the component which prevents its removal from cavity is termed an external undercut

Connecting member between register ring and runner.

It is a variation of hot runner mold in this type of molding. The outer surface of the material in the runner acts as a insulator.

Gap between core and cavity is called impression.Impression provides the shape of the component.

A valve ejector is basically a large diameter ejector pin. It is used for the injection of large components.

If the parting surfaces are not properly matched, the molding material from the impression will escape through the gap. This escaped melt is called the flash.

The stripper ring is a local stripper plate and it is used on molds with one or two impression only. The stripper ring is made to seat in the mold plate.

Shrinkage 3-4%. Main features of HDFE are high density, rigidity, strength, hardness and chemical resistance. Examples are milk bottle crates, fish boxes etc.

The main purpose of blade ejector is for the injection of very slender parts such as ribs and other projections which cannot be satisfactorily ejected by the standard type of ejector pin.

Shrinkage 0.3-0.8%. Its main properties are trparency and surface texture. Examples are Tool handle, goggles, TV screens.

  • Hot chamber process
  • Cold chamber process

The mold used for this process is similar that of the female half of the compression or blow mold auxiliary equipment on the machine heats the material and drags it over the cavity as indicated by the precise technique chosen.

Connecting member between gate and sprue bush.

A side core is a local core which is normally mounted at right angled to the mold axis for forming a hole or recess in the side face of a molding. The side cavity performs a similar function to the side core, in that it permits the molding of components which are not in line of draw. This element allows the components with a projection or projections on one or more of their side faces.

Male portion of the mold and it gives internal form.

  • No molded side products 
  • No separation of gait
  • Cycle time can be reduced

It is the maximum rate at which the screw can inject or shoot materials from the barrel during one shot.

When a basic mold is opened, there is only one space or “daylight “ between the two mold halves. This is called a single daylight mold.

This gate is used for single impression tubular shaped moldings on two plate molds.

Female portion of the mold and it gives external form.

Lack of fill, cold shut, severe chill, chill, flow lines

Hollows created on or in the molded part.

In this process, the plastic material is placed in the cavity and use a force for compressing the compound as the mold closes, these molds are generally used for thermosetting materials.

This is the general purpose gate and it is a rectangular channel machined in on mold plate to connect the runner to the impression.

It is used to align the mold with machine platen.

Blow molding is very much like compression molding because the blow mold generally closes on a hollow shape that has been deposited in between the halves of the mold. Air or gas pressure is introduced at the center. This internal pressure causes a flow of the heated material in to intimate contact with the relatively cold mold sections. Here the plastic material solidifies and is subsequently ejected.

This injection technique is used mainly for the injection of circular box type moldings and for moldings with thin wall sections.

Shrinkage 0.5-0.7%. It is known optical trparency, rigidity and toughness. Examples are goggles, lenses, safety helmets etc.