Question 1

Accepted Answer

The important consideration should be end product and what your definition of "REGRIND" is. Reprocessing your own internal scrap (if kept clean and uncontaminated with anything else) is a significantly different question basis than using unknown or unclassified "regrind" from outside sources.As to the end applications – many custom processors adopt a simple program internally like the 80:20 approach above simply because it generally insures inventory 'velocity' versus turning cash into useless warehouse ballast by using start-up scrap, sprues etc back into the product as the run progresses.There is no written down /prescribed guidelines for use of Regrind or process waste back into to Processing machines (Injection molding/Extrusion/Blow etc). For non-engineering products & commodity products in India, there are processors who use only Recycled/Regrind material for cost effectiveness. Generally, most of processes 80:20 virgin to regrind is preferred, but it's not a guideline. All depends upon type of product, property requirement & application of products etc.

Question 2

Accepted Answer

It's a small plastic injected piece that will be submitted to short period of time (2 seconds) of high temperature (95-105ºC approx.) in every cycle; this high temperature is produced by a filament where electric current passes through (like a house light bulb but hotter) for no more than 2 seconds in the process cycle. A complete process cycle last for about 45 seconds where the piece has time to cool off again. This plastic piece has to work for about 45-50 complete process cycles.PP or Nylon will work well (PE is very hard to flame retard and has a much lower softening point). I would however suggest that you look at a flame retarded nylon 6 or 66 that is specifically designed for this type of exposure. You want to look at the Glow Wire Flammability Index (IEC 60695-2-12) of the grade. You want to make sure that the materials rating (maximum temperature) is higher (maybe 50-100°C higher than your conditions, temperature, exposure time, part thickness, I say this because it is very difficult to estimate the radiated heat and resultant temperature). These grades are made by Sabic-IP (under the Starflam tradename), Lati, RTP, BASF and others.

Question 3

Accepted Answer

Gate types The two main gate systems are manually trimmed gates and automatically trimmed gates. The following examples show where they are used:1. Sprue gate: Used for large components, the gate mark is visible in component and no runner is required. e.g.: bucket molding (backside cylindrical gate mark visible and can be felt).2. Edge gate: Most suitable for square, rectangular components3. Ring gate: Most suitable for cylindrical components to eliminate weld line defect4. Diaphragm gate: Most suitable for hollow, cylindrical components5. Tab gate: Most suitable for solid, thick components6. Submarine gate: Used when auto de-gating is required to reduce cycle time7. Reverse taper sprue gate (Pin gate): Generally used in three plate molds.

Question 4

Accepted Answer

Ejection system types l Pin ejection—Cylindrical pins eject the finished component. In the case of square and rectangular components, a minimum of four pins (at the four corners) are required. In the case of cylindrical components, three equidistant pins (i.e. 120° apart) are required. The number of pins required may vary based on the component profile, size and area of ejection. This ejection system leaves visible ejection marks on the finished component.l Sleeve ejection—This type of ejection is preferred for (and limited to) cylindrical cores, where the core is fixed in the bottom plate. In this system, the ejection assembly consists of a sleeve that slides over the core and ejects the component. No visible ejection marks are apparent on the component.l Stripper plate ejection—This ejection is preferred for components with larger areas. This system calls for an additional plate (stripper) between the core and cavity plates. To avoid flash, the stripper plate remains in contact with the cavity plate and a gap is maintained between the cavity and core plate. Visible ejection marks are usually not noted on components.l Blade ejection—This type of ejection is preferred for thin, rectangular cross sections. Rectangular blades are inserted in cylindrical pins (or cylindrical pins are machined to rectangular cross sections) to create an appropriate ejection length for the component. For easy accommodation of the ejection pin head, a counter bore is provided in the ejection plates.l By rotation of core (internal threaded components)—Used for threaded components, where the component is automatically ejected by rotating the core insert.l Air ejection—Used to actuate the ejection pin fitted in the core using compressed air. The ejection pin is retracted using a spring.

Question 5

Accepted Answer

Hard Tooling -Steel/aluminum tools are used for the injection molding process for prototype or bridge, but these tools are mostly used for high volume production (100’s-100,000’s).-Steel/aluminum tools typically range in price from thousands to tens of thousands of dollars. And pending on the material and part geometry, the tool life can range from thousands to millions of parts. Soft Tooling -Silicone molds and the urethane process are used when a lower volume of parts is needed (1-100). This is because the tooling and piece price is more economical for lower quantities. On average, silicone tools usually cost in the hundreds to thousands of dollars, pending on the part geometry.-Silicone molds can be used for prototype, bridge and production of low volumes from one part to hundreds of parts. Most silicone molds are good for about 25 shots per cavity.

Question 6

Accepted Answer

Hard Tooling -Steel/aluminum tools are used for the injection molding process for prototype or bridge, but these tools are mostly used for high volume production (100’s-100,000’s).-Steel/aluminum tools typically range in price from thousands to tens of thousands of dollars. And pending on the material and part geometry, the tool life can range from thousands to millions of parts. Soft Tooling -Silicone molds and the urethane process are used when a lower volume of parts is needed (1-100). This is because the tooling and piece price is more economical for lower quantities. On average, silicone tools usually cost in the hundreds to thousands of dollars, pending on the part geometry.-Silicone molds can be used for prototype, bridge and production of low volumes from one part to hundreds of parts. Most silicone molds are good for about 25 shots per cavity.

Question 7

Accepted Answer

Longxiang as a experienced player in the line, we strive for customer satisfactions. So we ensure you that we will follow up every product we sell.Longxiang provide necessary technology and technical supports for all our products. We have decades of technicians available to assist in the assembly or the relevant support services whenever and wherever you need.Longxiang make compatible parts available whenever and wherever you want. We do as we say, for we have established mature logistic and inventory system to supply what you need.Longxiang are obliged to provide necessary maintenance, for which we have enough technicians in service.And last but not least, our responsive and helpful customer service force is available by below means.

Question 8

Accepted Answer

Plastic MaterialFeaturesApplicable products POMLow friction coefficient,Good geometric stabilityEspecially suitable for the production of gear and bearing      PA PA6Good elasticity,High impact strength,Water absorption is biggerSuitable for making general machinery parts, reduce friction wear parts, transmission parts, as well as chemical, instrumentation and so on. PA66Better than PA6,High strength,Good abrasion resistance PA610Similar to PA66,but small water absorption,Low stiffness PA1010Translucent,Small water absorption,Good cold resistance   PC Very good impact strengthm,Thermal stability, Glossiness,Inhibit bacteria,Flame retardant properties and stain resistanceElectrical and business equipment(computer components, connectors, ect.), Appliances(food processor, a refrigerator drawer, ect.), The transportation industry(the vehicle’s front and rear lights, dashboard, ect.) PETGTransparent,high strength,high wayward integrated featuresPlate, sheet, special-shaped material (film, bottles), cosmetics packaging   PPO Non-crystalline material,Moisture absorption of small,Poor liquidity,Low bibulous rate is about 0.06%Suitable for production of heat resistance, insulation parts, antifriction, wear parts, transmission parts, medical and eletronic parts(screws, fasteners and fittings )   PBTOne of the most tenacious engineering thermoplastic materials Have a very good chemical stability, mechanical strength, electrical insulation properties and thermal stability Home appliances (food processing blade, vacuum components, electric fans, hair dryer, coffee ware, etc.), electrical components (switch, electrical cabinet, fuse box, computer keyboard key, etc.), automotive industry (radiator shutters, panels, wheel cover, car body, door and window components, etc.)     PMMAExcellent optical properties and resistance to climate change.The white light penetrability is as high as 92%Have very low birefringenceHave room temperature creep propertyHave good impact resistance propertiesautomobile industry(signal equipment, instrument panel, etc.), pharmaceutical industry (ChuXie container, etc.), industrial applications (video, light scattering), consumer goods (drink cup, stationery, etc.)

Question 9

Accepted Answer

Question 10

Accepted Answer

Question 11

Accepted Answer

Plastic Mould Operation Manual

Question 12

Accepted Answer

In general, For plastic injection mold: 50% deposit, 30% before T1 sample, 20% after you confirm the sampleFor plastic injection parts: 50% deposit, 50% before shipmentFor rapid prototype: 100% deposit

Question 13

Accepted Answer

In general1-2 days for DFMEA report2-3 days for mold design and making mold drawing25-40 days for mold making.

Longxiang Group

FAQs