Working with Smaller Equipment in Manufacturing Cells
Assembly considerations are changing as most manufacturers recognize the value proposition of cellular manufacturing. Cellular manufacturing is a process of manufacturing which is a subsection of just-in-time manufacturing and lean manufacturing encompassing group technology. The goal of cellular manufacturing is to move as quickly as possible, making a wide variety of similar products, while making as little waste as possible.
Because there are multiple parts per assembly cell, utilizing this lean method of producing similar products using cells, or groups of team members, to facilitate operations by eliminating setup and unneeded costs between operations. Cells might be designed for a specific process, part, or a complete product.
Topper industrial uses the flexibility of daughter carts to meet the variety of cart height requirements within a confined area while considering material equipment flow and sequencing. From lift tables to tilt carts to rotation carts, delivering to a manufacturing cell for assembly provides a comprehensive flexibility versus the inefficient traffic of fork trucks throughout the pant.
One of the assembly metrics used most often is takt time. Takt is the German word for the baton that an orchestra conductor uses to regulate the tempo of the music. Takt time may be thought of as a measurable “beat time,” “rate time,” or “heartbeat.” In Lean, takt time is the rate at which a finished product needs to be completed in order to meet customer demand.
Takt time should not be confused with cycle time. Cycle time for a process is the time it takes for that process step to be completed. Takt time is the average demand from the customer and therefore the rate at which products should be produced.
One other metric is the flow rate usually expressed as an average rate. Flow time is the amount of time a flow unit spends in a business process from beginning to end, also known as the total processing time. If there is more than one path through the process, the flow time is equivalent to the length of the longest path. In the world of assembly within smaller manufacturing cells, smaller equipment is needed, and line-side delivery is part of the answer.
Presenting Parts Most Efficiently to Operators on the Line
Topper Industrial is asked daily how carts can present the parts better for the operators on the line. One solution is the tilt cart because if the parts allow a 30, 45, 60 or even 75-degree tilt ensuring the operator is always picking in the optimal ergonomic zone.
Topper Industrial engineers many different types of tilt carts. Tilt carts create a safe, controlled, and ergonomic delivery workstation line-side. A tilt cart is a rugged industrial cart consisting of a unique upper frame that is designed to fit a specific container and tilt to a desired angle. Topper Industrial’s tilt carts come equipped with a patented adjustable closed loop hydraulic cylinders that control the energy of the load as it is tilted. It provides for a safe and controlled tilt movement in a full to empty application. The most common requested degree of tilt is 30, 45, and 60 degrees, but the carts can be custom designed to virtually any angle. Tilt carts are designed as four-wheel or six-wheel carts. Topper Industrial also manufacturers unique side tilt carts.
Another cart that improves line-side deliver is a rotate cart. Topper Industrial uses a HD Bearing for easy and stable rotation for the operator (with an auto locking system that can lock the top every 90 or 180 degrees). This is a great option if the operator has an overhead lift assist that they are also coming back to pick the part in/near the same location every time.
Careful analysis and a few small modifications yield significant ergonomic improvements for assembly processes at manufacturing operations. Workplace injuries are not relegated to heavy machinery or falling objects. For assemblers, work-related repetitive motions are a common source of serious disorders, such as tendonitis or bursitis. Last year alone, there were more than 40,000 repetitive motion injuries in the United States.
Repetitive motion disorders (RMDs) are a family of musculoskeletal conditions that result from repeated motions performed during normal work. If assemblers repeat the same motions frequently and for prolonged periods of time, fatigue, and muscle-tendon strain can accumulate, resulting in RMDs. The effects of repetitive motions increase when unnatural or awkward postures and forceful exertions are involved.
The most common RMDs include carpal tunnel syndrome, tendonitis, trigger finger, and aggravation of pre-existing conditions, such as arthritis. These disorders are characterized by pain, tingling, numbness, swelling, or redness of the affected area, and the loss of flexibility and strength. For some individuals, there may be no visible sign of injury, although they may find it hard to perform easy tasks. Over time, RMDs can cause temporary or permanent damage to the muscles, nerves, tendons, and ligaments, as well as compression of nerves or tissue.
RMDs and other musculoskeletal disorders are among the most prevalent lost-time injuries and illnesses in almost every industry. They are costly. Employees affected by RMDs face long-term health issues. If surgery is required, they may even face a disability. Employers must then deal with reduced worker productivity, days away from work, worker compensation claims, and increased insurance premiums.
Manufacturing managers protect employees’ health by using carts that support both an ergonomic workplace and increase productivity. Improving safety, ergonomics, and throughput for assembly, integration, testing, finishing, and transportation operations are proven solutions for ergonomic rotation and consider safety factors backed by engineering stress and stability analyses. Topper Industrial supports customers in industries across North America, including aerospace, automotive, and agricultural machinery.
Kitting Defines Lean Manufacturing
Part kitting and sequencing translates into error proofing, track and trace, allowing line-side assembly variations without expanding a facility or compromising quality. Topper Industrial is a champion of material handling equipment that encourages and promotes lean manufacturing and kitting assembly; off-line inventory management shortens operator walk time. By bring materials systematically to the operators there is decreased line-side clutter on operator walk paths while permitting increased product types and variants.
Only in effective kitting is just-in-time line-side inventory achieved, which also reduces waste. Cart delivery can be easily and fully integrate kitting, sequencing, error proofing, and traceability once configured; it is easily replicated across operations within a plant and/or enterprise-wide.
Part Sequencing Shortens Operator Walk Time
Cart delivery ensures that valuable time is spent on part assembly rather than wasted time finding the correct parts. Topper Industrial carts are configured to a sequencing system for off-line part pickers to stagger or reverse order parts before placing them line-side for assembly. Sequencing of cart delivery can be automatically updated based on real-time production schedules, so parts arrive in time. Nothing need be loaded on a cart unless it is gated quality controlled and parts are traceable ensuring correct part placement is verified before moving further down the line. Vision inspection systems can check for incorrect or absent parts.
At each station, where off-line pickers are kitting or sequencing parts, carts arrive when needed, thus notifying workers of low part inventory or improper bin placement. With highly accurate error proofing systems, off-line pickers can adjust quickly, preventing line shutdowns. Parts are continuously tracked, giving purchasing better visibility into inventories; shortfalls and excesses are avoided.
Lean Assembly Kitting Eliminates Lineside Clutter
By creating cart-delivered line-side part kits, operator walk paths are clear and just-in-time line-side inventory eliminates waste. Delivery carts allow manufacturers to accomplish advancing competitive best-practices utilizing lean manufacturing.
As customers increasingly expect custom products, multi-model manufacturing becomes increasingly complex. The combination of a strong part kitting and sequencing application combined with error proofing and track and trace has given many manufacturers the capacity for variants without expanding a facility. Line-side assembly cart delivery means more space can improve throughput and voluminous SKU without increasing square footage.
Cart delivery provides a framework to redesign the conventional material supply systems throughout the manufacturing sector, and particularly the automotive supplier companies, by considering the demand characteristics and the bill-of materials of the products, on the basis of lean production principles.
INDUSTRIAL CART by TOPPER INDUSTRIAL
Pull-based (Kanban) systems often utilize assembly kitting to replenish components on the assembly line. Because the high material handling costs and space requirements, as well as many product customization requests, kanban systems using line-side delivery coordinate supplying components with relatively ease.
Although conventional Kanban systems require replenishment of components by containers, kitting often proves a better systematic method to save space in buffer areas of the assembly lines where products have common components. The kitting methodology was developed based on clustering of components into the kits. Replenishment of kits of components is coordinated by Kanban.
The time spent by the assembly line operators for checking the parts availability can be eliminated. Material feeding time is significantly reduced and time spent by the production planner for controlling the production requirements are reduced by half.
Efficient Pick-up and Drop-off Keeps Material Moving
Effective material flow in an assembly facility leads to reduced material handling costs and increased productivity. Topper Industrial has been committed to improving the flow of materials for an assembly facility by supplying custom material handling equipment that receives supplied parts through receiving docks and transfers the parts to material storage locations and then to part usage locations. The locations of the receiving docks, storage locations, and line locations are predetermined, but the assignment of parts to dock locations, storage locations, and the material flow paths through the facility are decision variables.
With line-side delivery, carts design decisions such as the dock strategy employed, and the configuration of the storage areas lead to additional decision variables. The goal is to reduce overall material handling costs by effectively receiving, storing, and transferring the material from loading docks to line locations using cart delivery. The Topper team runs various cart delivery routes and scenarios showing an improvement in the material handling costs of nearly ten percent as compared to the status quo.
Since the benefits of just-in-time (JIT) production philosophy were introduced, many production planners are viewing scheduling, machine idle time, and in-process inventory from a new perspective. Where once optimum levels of inventories, minimum machine idle time, and large batch sizes were thought to be measures of an efficient production system, now reducing set-up times, reducing batch sizes, and achieving zero inventory levels are economically sound procedures.
Efficient pick-up and drop-off using cart delivery keeps material moving. JIT production techniques can be thought of as “pulling” the in-process materials through the processing system. This means that as component parts are used to build units at assembly, a “signal” is sent to the previous processing station to have the quantity of assembled component parts replaced. This process then proceeds backward against the flow of production, through each previous processing station, creating the sense that the parts are being “pulled” through the system. This is unlike the typical manufacturing system where a demand is forecast, or an order placed, and the lot sizes for each component are determined for the first process station. The batches are then “pushed” forward through their processing stations to the finished state. Cart delivery is there from start to finish being able to follow one route doing the same value added work as that produced by upwards of twenty routes used to move material via fork lifts and fork trucks.
In automated flow production facilities which have a job shop orientation, a method for taking advantage of JIT techniques is the synchronization of processing stations. As in flow shop assembly lines where the assembly stations are balanced to keep the system operating smooth, automated processing systems and job shops can operate in a similar fashion. Production systems can use synchronization to avoid bottlenecks and keep the automated flow of material moving smoothly. Job shops, which cannot depend on relatively flat production demands, could at least synchronize the start and/or end of serial processing stations and the convergence of component arrival times at assembly.
Flow shops use balancing techniques to determine efficient labor and equipment requirements to keep the production system moving smoothly or in a synchronous mode. Other production systems can be designed to have activity times of the various processing station elements (load/unload, fixturing parts, process parts, etc.) adjusted to achieve synchronization.
Topper engineers find material handling equipment solutions with benefits based on the location, size, weight, frequency, and space available for each production and manufacturing application. Topper Industrial holds many patents which specialize in moving parts, taking packaging, ergonomics, and part presentation each essential to material handling equipment that promotes effective material flow. The primary goal of Topper Industrial is to safely move material using cart delivery and compatible equipment in a manner which is most efficient both in saving money and ensuring safety.
Material flow can be measured by reducing a single touch. Innovation in production assembly keeps employees safe, prevents errors, and keeps production material and processes moving.
About Topper Industrial
For more than twenty years, Topper Industrial, (www.topperindustrial.com) based just outside of Milwaukee, WI, has been a leader in the material handling equipment industry. The company’s product roster features industrial carts, conveyors, lifts, lifts & tilts, shipping racks, containers, casters, and cart components. From mother-daughter carts to quad steer carts to tilt carts and rotate carts, Topper’s material handling solutions make delivering material line side more effective through more efficient practices. Topper Industrial has a team of experienced professional experts able to assess and provide the right product for all material handling equipment requirements.
Topper Industrial is a proud member of MHI. Follow on Twitter @TopperInd or on LinkedIn.