In the world of manufacturing, the term “lead time” is used to define the period between when an order is placed and when that order is complete (i.e. ready for pick up or delivery.)
Lead time in manufacturing is important for all parties involved, as it ensures that orders are placed and fulfilled according to a predictable timetable established at the outset. Depending on the part and the processes which it requires, lead times can be fairly standard throughout the industry, but there are always circumstances that could extend or shorten production lead times. Knowing what goes into determining lead time can be extremely beneficial when quoting jobs or placing orders, and there helpful steps to consider when expediting lead time is a priority.
What Affects Production Lead Times In Manufacturing
There are quite a few factors that could affect production lead time.
One of the main considerations when determining production lead times is material/part availability. While many manufacturers will keep a certain amount of stock on hand, in many instances they must source-specific material or part components from their suppliers. This is subject to its own lead time from the vendor, which can vary widely based on availability.
Once material and components have arrived, machine/operator capacity is another factor to take into account. Production queues are generally determined days or weeks in advance, so lead times must leave enough wiggle room to ensure that all jobs can get through a given machine without creating too much of a bottleneck. Some manufacturers will offer an expedite option to move a specific job to the front of the line, but this generally comes at an added cost and can be to the detriment of other customers if not managed properly.
After production, many parts go out for secondary processing (heat treatment, surface finishing, etc.) These too will have lead times associated and must be accounted for when projecting the total duration of a project.
How To Reduce Lead Times
Now that we know some of the elements that go into determining lead time, what can we do to minimize this period and get parts produced faster? Though it’s not possible in every instance, there are a few ways that manufacturers can speed up production, and some steps that customers can take when designing/ordering parts to streamline the process and ensure that lead times remain as minimal as possible.
The One-Stop Shop
Relying on multiple vendors for individual aspects of manufacturing can pose a challenge when you want to get things done in a hurry. Instead, a proven method to minimize lead time is to have one shop oversee all facets of production. This could entail material sourcing, machining/fabrication, secondary processes, and assembly/packaging. By limiting the number of parties involved, you can help mitigate unexpected delays and significantly streamline the manufacturing process. While not everyone offers this service, it can be a game-changer when it comes to limiting production time, and it is definitely worth a discussion with your machine shop to determine their capabilities and contacts to see if they can shoulder more of the burden when it comes to coordinating and managing additional operations.
Production Capacity
Have a conversation with your manufacturer about capacity. Do they have open machine time? How far out is their production queue? Are they expecting any large orders that would tie up equipment for a prolonged period? Production capacity is a huge factor when it comes to determining the lead time. If machines are open and operators are free, it can be easy to quickly push a job through with delay. On the other hand, it there is a backlog of orders to get through a machine, it can take weeks before new orders make it to the front of the line.
Most machine shops will be upfront about their capacity and will communicate realistic lead times to allow enough wiggle room so that they can have parts ready by a given date. That said, a quoted lead time is always subject to change. If a customer inquires about a part and then waits a few weeks or months to order, production capacity (not to mention material availability) could change dramatically in that time. It’s best to order parts as close to the date of the quote as possible.
Order Frequency / Forecasting
It can be more cost-effective to order parts in large quantities, but if time is of the essence, it may be worth considering lowering your numbers to get items through production quicker. By decreasing the quantity, and increasing the frequency at which orders are being placed, you can help ensure that you can meet customer demand without prolonged lead times.
It can also be helpful to share order forecasts with your manufacturer so they can plan ahead. Many shops will produce extra parts if they are expecting upcoming orders, and some will even agree to stock a specified amount of product that they can release when customers are in a pinch.
Standardize Everything
Custom features add time and money to a project, so it is always advised to stick to industry standards whenever possible.
This applies to material, which comes in standard sizes/thicknesses and types. Many machine shops will keep stock on hand, but when specialty material is required, it will need to be ordered from outside vendors and that could add days or weeks to lead time.
This also can apply to part design. Relying on standard sizes for machined features (holes, taps, radii, etc.) helps ensure that shops will have tooling available to machine parts as soon as an order is placed. Custom features require custom tooling, which will need to be acquired prior to production, and will come at a cost (both in time and money.) It can be worth discussing substitutions with your manufacturer, as certain materials/tooling may be more readily available than what was originally specified. By substituting for something on-hand, it can significantly reduce production lead times.