Separate metering from mixing
Metering establishes how much of a component is added. Mixing distributes the ingredients through a blend. If the wrong quantities enter the mixer, a longer mixing cycle does not correct the recipe.
| Arrangement | Where quantities are established | Material sequence |
|---|---|---|
| GB gravimetric batch blender | Components are weighed for a batch. | Supply ingredients → weigh → mix → feed production. |
| CM volumetric doser | Calibrated screw feeding meters masterbatch or additives by volume. | Add the dosed ingredient to the main-material flow at the process. |
| RM batch mixer | Measure ingredients in a separate preparation step. | Load the prepared charge → mix → transfer to production. |
GB1-4 and GB2-4 have four material hoppers. Describe resin, masterbatch, additives or regrind separately, with each ingredient's form and proportion. A gravimetric batch blender weighs components before mixing; a continuous loss-in-weight feeder instead monitors decreasing feeder weight to control delivery. These are different arrangements.
Check what the dosing setting represents
A volumetric setting connects a delivered volume to the required mass through calibration. Collecting material over a defined interval and weighing it establishes the delivery setting. A change in bulk density can change the mass delivered at that setting, so review calibration when changing material or the required addition.
State whether recipe percentages refer to the whole blend or to the main resin. A proportion based on virgin resin is a different instruction from the same proportion based on the total mixture. Keep that basis with the recipe, including when regrind is used.
For any accuracy statement, identify the material, operating setting and test method. Metering performance and the finished product's acceptance requirements need separate checks; neither a dosing setting nor a weighing principle demonstrates final product quality.
Decide which part of the workflow needs to change
If separate ingredient measurement and batch mixing already meet your requirements, retaining the existing mixer may be reasonable. Check the preparation records and handling steps before replacing equipment. For process addition, review CM dosing; for weighed recipe batches, review the GB arrangement.
The RM catalogue describes batch preparation of pellets and color masterbatch. Its model names identify mixer variants, not continuous processing rates. Keep batch quantity and mixing frequency separate from the receiving machine's consumption. For GB, also include the smallest addition and commonly used recipes. For another mixing construction, review the RSM vertical screw mixer.
Include changeovers and installation in the comparison
Changing a recipe setting does not empty material already in the equipment. Include the hoppers, dosing or weighing section, mixing chamber and transfer route in your changeover plan. Show how material is loaded, discharged and collected, and how often resin or color changes.
The GB catalogue describes machine mounting and optional floor mounting. Compare refill access, supporting space, discharge connections and the route to production. Any loader and conveying route require their own specification.
For CM, identify single or double dosing needs, the main-material feed, connection and machine signal. Include whether the receiving machine's demand stays steady or changes. For every proposal, confirm the quoted model, hoppers, mixing and control components, and installation scope. Send RHONG the ingredient list, recipe basis and proposed layout to discuss the equipment arrangement.
Technical references
Conair explains volumetric calibration; motan distinguishes batch and loss-in-weight dosing. Maguire describes virgin-resin-based recipe proportions.