Fruit Distribution Centre
Montemurro recently completed the design of a complete fruit distribution centre.
The problem
The client had a soft fruit dispenser connected to a fruit sorting conveyor and a sorted fruit dispenser (via elevator conveyor). The fruits were dispensed on a PVC belt, then conveyed to the sorting conveyor followed by an inclined conveyor. Further downstream the fruits were manually collected, put into punnets and transported to the packaging machine. The procedure was labour intensive and inefficient, with a throughput of less than 5 punnets a minute.
The PVC belt was deemed too wide for its application and a fixed arm was used to converge the fruits to a narrower track in order to facilitate sorting by the workers. This convergence caused fruit damage and other productivity issues.
The sorting conveyor comprised of rollers with wheels that spun about its axis (clockwise) while moving forward. This caused the fruit to spin anti-clockwise (from the viewpoint of the sorting workers) and allowed a full inspection of the product (360° product spin). The wheels, rollers and background were black making it difficult to identify possible flaws on fruits. Also, the conveyor was believed to be too wide for the application, making it hard to reach fruits furthest from the workers (they work from only on one side of the conveyor). Furthermore the conveyor working height was inadequate, requiring a working platform to support workers.
Once the fruits were sorted they were manually put into punnets, which were then put into an automatic packaging machine. There was no automated system to handle the packaged punnets or rejects.
Montemurro’s engineers determined a new automated conveyor system was required to link the fruit dispenser machine to the punnet packaging machine, handle the fruit rejects, facilitate the sorting process and handle the final packaged punnets. The system had to be able to handle up to 50 punnets per minute and make the pre-sorted fruits available to workers for enough time to enable further sorting and filling of the punnets.
The solution
The project’s main objectives were to link the fresh fruit dispenser to the packaging machine in order to create a “series” production style line, while also providing a reject handling conveyor along with a packaged product handling rotary device. The proposed system would greatly improve the production rate: it was designed to produce about 50 punnets per minute.
The fresh fruit dispenser was re-utilized: a narrower conveyor using a polymer material modular belt was attached to it. This conveyor section featured an inclined section, lowering the freshly dispensed fruits to a more suitable working height. This was followed by a new sorting conveyor, which was designed to a more suitable width. It also incorporated white polymer material rollers and a white background to facilitate fruit inspection.
An infinite loop conveyor (self-intersecting) system was placed after the sorting conveyor. This loop conveyor incorporated a belt of a polymer material and modular construction. The belts were designed to run in an opposite direction to each other and to use low friction guide rails to slide the fruits into one another, creating an anti-clockwise circulation of the products. This allowed enough accumulation and time for the workers to fill the punnets and reject unwanted products.
A reject conveyor was installed concealed under the infinite loop, sorting and fruit in-feed conveyors (in a direction opposite to fruit in-feed), conveying the rejects to a bin adjacent to the fresh fruit dispenser. The rejects were elevated so they fell inside the reject bin, which could be removed with a forklift. Chutes were placed along the infinite loop conveyor directing rejects to the conveyor. The belt selected for task was a polymer modular type with a flush grid in order to facilitate cleaning “wash down”.
A de-nesting machine was installed to feed empty punnets to a slender conveyor with a chain style modular polymer material belt. The conveyor was built to accommodate the two sizes of punnets utilised. It starts adjacent to the de-stacker, and is tasked with feeding the empty punnets to workers on the infinite loop conveyor (flush with the conveyor). Full punnets are then conveyed to the scale/reject unit (provided by Oasis Fresh) and from there into an accumulation/indexing conveyor that feeds the punnets to the packaging machine.
The packaging machine employs an indexed flighted conveyor, requiring an indexed in-feed. The indexing is accomplished via a set of friction top modular conveyors controlled by a central control system. The system achieves the purpose of accumulation and timing for the indexing of punnets.
Once the packaged punnets exit the machine they are transferred to a rotary “Chinese hat” table, serving the purpose of accumulation for boxing/palletizing. The rotary table is manufactured of stainless steel with a “lip” on its periphery.
The production rate is controlled by use of VSDs (Variable Speed Drives) on conveyor drive units. As a guideline most VSDs are of the Variable Frequency type and are limited to around ±20% of rated drive unit speed.
Montemurro recently completed the design of a complete fruit distribution centre.
The problem
The client had a soft fruit dispenser connected to a fruit sorting conveyor and a sorted fruit dispenser (via elevator conveyor). The fruits were dispensed on a PVC belt, then conveyed to the sorting conveyor followed by an inclined conveyor. Further downstream the fruits were manually collected, put into punnets and transported to the packaging machine. The procedure was labour intensive and inefficient, with a throughput of less than 5 punnets a minute.
The PVC belt was deemed too wide for its application and a fixed arm was used to converge the fruits to a narrower track in order to facilitate sorting by the workers. This convergence caused fruit damage and other productivity issues.
The sorting conveyor comprised of rollers with wheels that spun about its axis (clockwise) while moving forward. This caused the fruit to spin anti-clockwise (from the viewpoint of the sorting workers) and allowed a full inspection of the product (360° product spin). The wheels, rollers and background were black making it difficult to identify possible flaws on fruits. Also, the conveyor was believed to be too wide for the application, making it hard to reach fruits furthest from the workers (they work from only on one side of the conveyor). Furthermore the conveyor working height was inadequate, requiring a working platform to support workers.
Once the fruits were sorted they were manually put into punnets, which were then put into an automatic packaging machine. There was no automated system to handle the packaged punnets or rejects.
Montemurro’s engineers determined a new automated conveyor system was required to link the fruit dispenser machine to the punnet packaging machine, handle the fruit rejects, facilitate the sorting process and handle the final packaged punnets. The system had to be able to handle up to 50 punnets per minute and make the pre-sorted fruits available to workers for enough time to enable further sorting and filling of the punnets.
The solution
The project’s main objectives were to link the fresh fruit dispenser to the packaging machine in order to create a “series” production style line, while also providing a reject handling conveyor along with a packaged product handling rotary device. The proposed system would greatly improve the production rate: it was designed to produce about 50 punnets per minute.
The fresh fruit dispenser was re-utilized: a narrower conveyor using a polymer material modular belt was attached to it. This conveyor section featured an inclined section, lowering the freshly dispensed fruits to a more suitable working height. This was followed by a new sorting conveyor, which was designed to a more suitable width. It also incorporated white polymer material rollers and a white background to facilitate fruit inspection.
An infinite loop conveyor (self-intersecting) system was placed after the sorting conveyor. This loop conveyor incorporated a belt of a polymer material and modular construction. The belts were designed to run in an opposite direction to each other and to use low friction guide rails to slide the fruits into one another, creating an anti-clockwise circulation of the products. This allowed enough accumulation and time for the workers to fill the punnets and reject unwanted products.
A reject conveyor was installed concealed under the infinite loop, sorting and fruit in-feed conveyors (in a direction opposite to fruit in-feed), conveying the rejects to a bin adjacent to the fresh fruit dispenser. The rejects were elevated so they fell inside the reject bin, which could be removed with a forklift. Chutes were placed along the infinite loop conveyor directing rejects to the conveyor. The belt selected for task was a polymer modular type with a flush grid in order to facilitate cleaning “wash down”.
A de-nesting machine was installed to feed empty punnets to a slender conveyor with a chain style modular polymer material belt. The conveyor was built to accommodate the two sizes of punnets utilised. It starts adjacent to the de-stacker, and is tasked with feeding the empty punnets to workers on the infinite loop conveyor (flush with the conveyor). Full punnets are then conveyed to the scale/reject unit (provided by Oasis Fresh) and from there into an accumulation/indexing conveyor that feeds the punnets to the packaging machine.
The packaging machine employs an indexed flighted conveyor, requiring an indexed in-feed. The indexing is accomplished via a set of friction top modular conveyors controlled by a central control system. The system achieves the purpose of accumulation and timing for the indexing of punnets.
Once the packaged punnets exit the machine they are transferred to a rotary “Chinese hat” table, serving the purpose of accumulation for boxing/palletizing. The rotary table is manufactured of stainless steel with a “lip” on its periphery.
The production rate is controlled by use of VSDs (Variable Speed Drives) on conveyor drive units. As a guideline most VSDs are of the Variable Frequency type and are limited to around ±20% of rated drive unit speed.