Ingredient weighing

The systems used for ingredient weighing can vary from a totally manual system to a totally automated system where the ingredients are untouched by human hands. The critical role of the ingredient weighing system. 

Screw conveyors are used to transport particulate materials within a stores or ingredient weighing area. 

Liquid ingredient weighing can be an area of considerable problem when accuracy of addition is vital and dispensing equipment, fitted with heaters where required are very necessary to reduce compound variability. 

Advances in quality control requirements for rubber compounds have demanded that special care is exercised in the weighing of the various fillers and critical small volume powders necessary for the formulation. Ingredient weighing systems are available which can be tailored to the specific requirements of individual factories. Additional components can include conveyors, bagging units and pneumatic conveyance systems. 

Through a keyboard, the computer operator can enter the formulas and number of batches required for the production each day. The computer can hold numerous formulas. A sequential weighing of each ingredient designated by the formula used is started by computer command. The ingredients weighed are discharged into one... 

Summary report of the amount of each ingredient weighed Summary of the amount of formulas run Inventory of ingredients remaining in storage in various tanks Data transfer to main computer for accounting purposes... 

Weighing is the operation of determining the mass of any material as represented by one or more objects or by a quantity of bulk material. Proportioning is the control, by weighing, of relative quantities of two or more ingredients according to a specific recipe in order to make a mixed product, or to prepare the ingredients for use in a chemical process. 

The main features in which the Radford process differs from the batch operation are in thermal dehydration and compounding. Water-wet nitrocellulose on a continuous vacuum belt filter is vacuum-dried followed by hot air transfusion (80°C) to reduce the moisture to less than 2%. After cooling, alcohol is sprayed on the nitrocellulose to a concentration of 15—20%. The alcohol-wet nitrocellulose is then transferred from a surge feeder to a compounder by a continuous weigh-belt along with the other ingredients of the composition, which are also weighed and added automatically. 

Yeast may be suspended into a slurry and stored under refrigeration for short-time intervals to expedite its transport and metering into mixers. Water is metered into mixers rather than weighed. Minor ingredients may be weighed directly from their containers or they may be suspended in water slurries which are subsequently metered into mixers (1,3—5). 

Considerations such as these may make it desirable to consider automatic weighing and batch accumulation, metering of liquid ingredients, and automatic control of various time cycles. 

Care should be taken to avoid powerbil suction or air flow on the mixer or the weigh hopper from which the ingredients feed into the mixer. If the dust-collection suction on the mixer is too strong, vital ingredients may be sucked out. If the dust-collec tion suction on the weighing system is too strong, errors in weighing may result. 

Ibuprofen, the active ingredient in Advil , is made up of carbon, hydrogen, and oxygen atoms. When a sample of ibuprofen, weighing 5.000 g, burns in oxygen, 13.86 g of C02 and 3.926 g of water are obtained. What is the simplest formula of ibuprofen ... 

It is usually done by computer controlled electronic weighing scales that supply precise amounts of each ingredient to a high intensity mixer. The still-dry, free-flowing blend is then charged to a feed hopper where it is screw fed into a continuous mixer such as an extruder and/or kneader. Under the action of a mixer s reciprocating screw in the confined volume of the mixer chamber, the blend begins to flux or masticate into the required plastic state. 

To remove the excipient, the tablet was ground to a powder and a weighed portion treated with a known volume of a mixture of 5% glacial acetic acid in methanol. The slurry was well stirred to ensure all the active ingredients were dissolved and the mixture was filtered. 

The total-release foggers (6 oz) contained chlorpyrifos (1.000%), piperonyl butoxide (0.100%), pyrethrins (0.050%), N-octyl bicycloheptene dicarboxim-ide (0.166%), and inert ingredients, including petroleum distillates (KRID , K-Mart Corp. Troy, MI). The aerosol cans were weighed before and after use to measure discharge. 

An obsolescent term for compound room - the area where the elastomers and compounding ingredients are weighed out in the proportions called for by the compound formula, prior to the mixing process. 

A mix consisting of elastomer and generally only one other ingredient, the proportion of which is much higher than will be present in the final production mix. Masterbatches are used for cleanliness, convenience, accuracy of weighing small quantities of accelerators, etc. Although it... 

Rubber process dust is dust arising in the stages of mbber manufacture where ingredients are handled, weighed, added to or mixed with uncured material or synthetic elastomers. The aggregated maximum exposure limit in the UK is 6 mg/m3 (EH40/2000). The exception is chemicals for which specific exposure limits exist. 

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