Continuous Extrusion vs Accumulator Head Blow Molding: A CFO-Oriented Buying Guide

Why This Choice Matters to Your P&L

Why your blow molding head type is a board-level decision

When you invest in an extrusion blow molding line, you’re not just buying a machine. You’re locking in a cost structure for the next 5–10 years. The way the plastic melt is delivered to the mold – your head type – sits right at the core of that structure.

Extrusion blow molding is the process that turns plastic pellets into hollow parts like Botellas de HDPE, jerrycans, drums, y tanks. Pellets are melted, pushed through a head to form a molten tube, then blown inside a mold to match the container shape. It sounds simple, but the details of how that melt is handled drive your resin usage, cycle time, and scrap.

In this guide, we focus on two head concepts you’ll be asked to choose between: continuous extrusion como accumulator head. Both can make good parts. The question is which one supports the margin structure and growth plan of your business. That is why this is not just an engineering choice. It’s a board-level decision that affects EBITDA, cash flow, and your exit story.

Who this guide is for (CFOs, factory managers, founders)

If you are a CFO, you’re probably asking a very direct question:
“Does it really pay off to bring packaging in-house, and how do I avoid buying the wrong line?”

If you are a factory or operations manager, your focus is slightly different:
“How do I design a line that hits our OEE targets, fits our people, and doesn’t turn into a maintenance nightmare in year 2 or 3?”

If you are a growth-stage CPG founder, you may be stuck between rising bottle prices, inconsistent supply, and investors pushing you to secure your supply chain. You need to know whether a moldeo por soplado line is a strategic asset or a distraction.

In all three roles, the common point is simple: you sign the PO. Once you do, you own the payback period, the downtime risk, and the long-term cost per bottle or drum. Choosing between continuous extrusion and an accumulator head is part of that responsibility.

What is at stake financially

The head type you choose quietly shapes multiple lines on your P&L for years. It affects:

• Capex size and payback years
  • A continuous extrusion line for small and medium bottles is usually a lower-ticket entry.
  • An accumulator-head system for large drums and tanks is a bigger initial check, but it may cover heavier tonnage with fewer machines.
• Resin grams per bottle or per drum
  • Better wall-thickness control can cut a few grams off every part without risking failures.
  • On 10 million bottles, saving just 2 g each equals 20,000 kg of resin per year.
• Scrap rate and regrind levels
  • Sagging parisons and unstable thickness show up as short shots, leaks, and rejects.
  • An extra 1–2% scrap on heavy drums is real money when each part weighs 5–10 kg.
• Energy cost per 1,000 containers
  • Different head concepts and cycle patterns use different kWh/kg.
  • Over 5–10 years, small differences in kWh add up, especially if your tariff moves up.
• Changeover speed and SKU agility
  • If mold changes drag from 60 minutos to 3 hours, your “flexible” line becomes a bottleneck.
  • Slow changeovers mean overtime, missed orders, and lost contribution margin.

This isn’t about “nice-to-have” technical features. The head type sits upstream of unit cost, line uptime, and your ability to launch new SKUs without breaking the factory. It is not a “technical option”; it changes your margin.

How to use this guide (fast-track for busy people)

Different people in your team will use this guide in different ways.

If you’re in operations or engineering, you’ll probably read most sections. You’ll want the technical logic of how continuous and accumulator heads behave, how they fit different SKUs, and what that means for maintenance, staffing, and layout.

If you’re a CFO o founder with limited time, you can skim the early sections and jump straight to The Money Side: TCO and ROI of Continuous vs Accumulator. That is where we walk through total cost of ownership, build simple scenarios, and show how changes in resin, scrap, and energy feed into payback years.

Here’s how the rest of the guide is structured:

• Continuous Extrusion vs Accumulator Head: Plain-Language Basics explains, in plain language, what actually happens inside an extrusion blow molding machine and how continuous and accumulator heads differ in practice.
• Matching Head Type to Product Mix, Resin and Growth Stage helps you map your product mix, resin strategy, and growth stage to the right head concept instead of guessing from brochures.
• The Money Side: TCO and ROI of Continuous vs Accumulator builds a simple TCO and ROI framework and runs through two concrete scenarios: bringing 1 L bottles in-house and adding 200 L drum capacity.
• Quality, Risk, and Sustainability Trade-offs focuses on quality, risk, and sustainability, including wall-thickness control, audits, and PCR expectations from retailers.
• Scaling Roadmaps: From First Line to Full Factory looks at scaling roadmaps: how first-time investors and OEM factories can mix head types across multiple lines.
• Decision Checklist and Vendor Questions wraps up with a decision checklist and vendor questions you can use when you compare quotes.
• Summary and Next Steps gives a short summary and clear next steps for your project team.

ROI Callout – Why small numbers matter
If you can shave just 0.8 cents per bottle at 10,000,000 units per year, that’s $80,000 of annual margin. Over 7 years, that’s $560,000 before tax, without even counting energy or scrap improvements. The right head choice makes that kind of improvement possible.

At the end of this first section, if you already know extrusion blow molding is part of your strategy and you want to see real machine options, you can explore the LEKA portfolio here:
See the full LEKA extrusion blow molding range (0–2000 L).

Continuous Extrusion vs Accumulator Head: Plain-Language Basics

What actually happens in an extrusion blow molding machine

Before you compare head types, it helps to see the whole process in simple steps. An máquina de moldeo por soplado por extrusión always follows the same basic logic:

1. Plastic pellets are fed into an extrusor and melted into a homogeneous melt.
2. The melt is pushed through a head to form a hot tube called a tubular.
3. A mold closes around this parison.
4. Air is blown inside, forcing the parison against the mold wall to create the final shape.
5. The part cools, the mold opens, and the bottle, jerrycan, drum, or tank is removed.

El tubular is the critical part here. Think of it as the molten plastic tube that becomes your container. How that tube is formed, controlled, and delivered into the mold is what separates continuous extrusion from accumulator head technology. Your choice affects cycle time, wall thickness, scrap rate, and ultimately cost per part.

Continuous extrusion – the “running tap” of plastic

In a continuous extrusion head, the melt flows in a steady, uninterrupted stream, similar to a running tap. The extruder keeps pushing plastic through the head, forming a constant parison. Shuttle or wheel stations move in, grab a section of this tube, cut it, close the mold, and blow the part.

For small and medium containers, this has clear advantages:

• High output per hour – you are continuously feeding material, so the machine can produce many small and medium bottles in parallel or in quick cycles.
• Strong fit for HDPE and PP bottles and jerrycans in the sub-1 L, 1 L, 3 L, up to around 30 L range, depending on design.
• Fewer moving parts in the head, which can help with stability and maintenance if the design is robust.

The trade-offs appear as parts get larger or taller:

• The parison hangs under its own weight while the mold closes. On long or heavy parisons, gravity causes sag, leading to uneven wall thickness (thin at the top or bottom).
• This makes very large, thick-walled parts harder to control economically. You can compensate with programming and process know-how, but the physics always push against you.

For many CPG brands como OEM bottle factories, continuous extrusion is the default for their main volume: shampoo bottles, detergent bottles, edible oil bottles, and standard jerrycans.

To see this in real machines, refer to:
LEKA continuous extrusion machines for bottles and jerrycans.

Accumulator head – the “bucket then dump” approach

An accumulator head takes a different route. Instead of pushing melt out continuously, the machine first stores a defined volume of melt inside a chamber – like filling a bucket. Once that chamber reaches the programmed shot size, a ram pushes the entire charge out through the die, forming a thick parison in one shot.

Key strengths of this approach:

• Better wall-thickness programming – because the parison is shorter in hanging time and pushed out in a single stroke, you have more control over where material goes (corners, bottoms, threads, handle legs, impact zones).
• Ideal for large parts such as 120 L, 200 L drums, 500+ L tanks, and other heavy technical parts where each container can weigh several kilograms.
• Adds stability when you need very thick walls or multi-layer structures for chemicals, lubricants, or embalaje industrial.

The trade-offs are clear and need to be justified by your business case:

• Higher capex – the head itself is more complex and built for heavy shot weights.
• Bigger footprint and infrastructure needs – you often combine the accumulator with larger extruders, more powerful drives, and more robust handling.
• Slower cycles, but each cycle produces a much heavier part, so your hourly output is measured in kg/hour o drums/hour rather than bottles.

This is the realm of large-part extrusion moldeo por soplado. In LEKA’s portfolio, this logic sits behind the large-part and drum-focused EBM platforms, often used for drums, IBCs, and industrial tanks. When you think about 250 L containers or beyond, you are firmly in “bucket” territory, not “tap” territory.

These solutions are described in more detail under
LEKA’s extrusion blow molding machines for drums and industrial parts.

A non-technical analogy (for finance & founders)

For non-engineers, the easiest way to see the difference is with liquids:

• Continuous extrusion is like leaving a tap open and moving cups through the stream. Each time, you cut the flow and catch just enough to fill a cup. This works perfectly as long as the cups are small and you move them quickly.
• Cabeza acumuladora is like filling a bucket, and when it’s full, you dump the whole bucket into a mold in one go. This is what you do when you need to fill big containers that must be consistent and robust.

In other words: bottles and small jerrycans are usually “tap jobs”; drums and tanks are “bucket jobs.”

If you try to run drum-sized jobs with a tap setup, you spend money fighting basic physics. If you buy a bucket setup for only cup-sized jobs, you tie up capital in capability you don’t really need.

Side-by-side technical summary

Use this simple technical comparison as a shared reference. It’s not a full spec, but it keeps everyone on the same page in meetings.

From a business view, this table is your first filter. If most of your revenue will come from high-volume small bottles, you start on the left. If your strategy depends on large drums or tanks, you need the right-hand column. The rest of this guide builds on that split and translates it into cost, risk, and growth decisions.

Matching Head Type to Product Mix, Resin and Growth Stage

Start from your product map, not the machine brochure

When we talk about continuous extrusion or accumulator head, we’re not really talking about steel. We’re talking about your SKU list, your forecast, and your 5-year plan.

So before anyone sends you a quote, sit with your team and:

• List all current SKUs: size (ml / L), material (HDPE / PP), shape, color.
• Mark annual volume for each: k units/year.
• Note margin importance: which SKUs carry the highest contribution.
• Add your 2–3 year roadmap: refill packs, bulk packs, drums, new markets.

Once that is on the table, the head choice becomes a strategy decision, not a guessing game based on catalog pictures.

There are two typical personas here:

• Growth-stage CPG brand mainly in the 1–5 L bottle space, maybe with a 20–30 L refill in the future.
• OEM bottle or chemical packaging factory running a wide mix that may stretch from 250 ml bottles up to 220 L drums.

The right answer for each is different. And choosing wrong locks you into the wrong cost base for 5–10 years.

When continuous extrusion is the default

For most brands and many OEMs, continuous extrusion is the logical starting point. If 90% of your volume is in small and medium containers, your money is made on units/hour, not kg/shot.

Continuous extrusion usually makes sense when:

• 90%+ of SKUs are under 30 L.
• You live mostly in HDPE / PP bottles for personal care, home care, food, or agrochem.
• You expect frequent changeovers and need the line to follow marketing, not block it.
• You care a lot about EGE (Eficiencia General de los Equipos) and labor efficiency on high-volume bottles.

Think about a startup detergent brand with 500 ml, 1 L and 3 L bottles. The entire marketing story, retail presence and investor pitch sits on these SKUs. In that case, a well-chosen continuous EBM line can give you:

• Stable cost/bottle across millions of units.
• Fast changeovers between label variants and sizes.
• A clear payback story you can show your board.

To make this tangible, you can frame it like this:

If most of your revenue sits in these rows, continuous should be your default. You may never need an accumulator head at all, or you might add it much later when your product strategy truly requires it.

When an accumulator head becomes non-negotiable

There is a clear point where continuous extrusion stops being efficient and starts working against your P&L. That point is when parts become large, heavy, and performance-critical.

An accumulator head moves from “nice to have” to “mandatory” when:

• Your key SKUs are above roughly 60–80 L.
• You need very thick walls, with strict specs on drop tests and stacking.
• You’re dealing with UN drums, chemical tanks, or lube oil drums that travel globally.
• A single defect can cost you much more than the resin in that drum.

Example: a lube oil supplier adding 220 L drums for export. In this case:

• Each drum might weigh 8–10 kg.
• Losing 2% to scrap equals 16–20 tons of resin per 100,000 drums.
• Poor wall control can lead to leaks, claims, and lost contracts.

Here, forcing a continuous system to “stretch” into drum territory can cost you far more over 5 years than the capex difference to an accumulator.

If your revenue story depends on anything in this table, you should treat an accumulator head as a non-negotiable asset, not an optional upgrade.

Resin and PCR considerations

From a resin standpoint, both head types can run HDPE and PP, and both can be engineered to handle PCR blends. The business question is not “can it melt PCR?” but “does it keep my process stable and my scrap tight when I run 20–50% PCR?”.

For CFOs and factory managers, the key points are:

• Resin is usually 60–80% of total container cost. Tiny improvements in grams/part matter.
• PCR is often more expensive per kg but reduces tax, compliance or brand-pressure costs.
• Instability with PCR shows up as higher scrap, more rework, and line downtime.

That’s why, when you discuss resin and PCR, you should ask suppliers for:

• Real PCR trial data at your target percentages (20%, 30%, 50%).
• Video or logged data from similar molds and weights, not just generic claims.

The head choice itself is less important than overall temperature control, screw design, and automation, but it still interacts with how easily you can tune thickness and maintain part performance while changing recipes.

Where stretch blow fits (short context only)

Just to avoid confusion: if you are talking about PET bottles for water, CSD, or juice, you are probably not in the extrusion blow world at all. You are in stretch moldeo por soplado, where the economics and line design are different.

From a business view, you should separate:

• HDPE / PP containers → moldeo por soplado por extrusión (continuous vs accumulator head).
• PET bottles → moldeo por soplado de estirado.

If PET is on your roadmap, and you want to compare the business case of PET vs HDPE for certain SKUs, it’s better to look at that in a dedicated view:
If you are also considering PET, see our stretch blow molding overview:
Máquina de moldeo por estirado-soplado.

That way, you keep a clean decision tree: first choose material and container family, then choose head type inside extrusion blow.

The Money Side: TCO and ROI of Continuous vs Accumulator

Total Cost of Ownership – the simple framework

When you compare continuous extrusion and accumulator head systems, the only honest way to do it is on Costo Total de Propiedad (CTP), not sticker price. Over 5–10 years, your real cost per bottle or drum is driven by five blocks:

• Capex + depreciation
• Resin usage (grams/part)
• Energy (kWh/kg)
• Labor (operators, helpers, QC)
• Scrap and rework

If you keep these in view, the head decision becomes a finance discussion, not just an engineering debate. Use this simple comparison in internal meetings:

This framework lets you anchor the discussion on long-term cost, not only on the initial invoice.

Capex ranges and financing logic

In most real projects, you’ll see something like this:

• A continuous EBM line for bottles sits at a lower capex level and can cover several million bottles per year.
• An accumulator-head drum line is a heavier investment, but each line can cover serious tonnage in 120–220 L drums or larger tanks.

From a finance standpoint, you rarely fund these from pure cash. The mix is usually:

• Bank loans over 5–7 years
• Investor capital for strategic vertical integration
• Government grants or incentives for capacity and sustainability

So the capex discussion should always be tied to a payback window and a target IRR. A more expensive accumulator line can easily be the smarter choice if it saves enough resin and scrap over 5–10 years.

Scenario A – Brand bringing 1 L bottles in-house (continuous)

Take a simple case so everyone can see the math. Assume:

• Annual volume: 10,000,000 bottles of 1 L
• Current buy-in price from a supplier: $0.12 per bottle
• Target in-house bottle weight: 50 g (0.05 kg) HDPE
• Resin price: $1.60/kg

A realistic in-house cost breakdown on a continuous EBM line could look like this:

Now compare:

• Outsourced cost: $0.12 × 10,000,000 = $1,200,000/year
• In-house cost: $0.10 × 10,000,000 = $1,000,000/year

Annual saving in this simple scenario: $200,000

If your complete continuous EBM line (machine, molds, downstream) is, say, $800,000 installed, then:

Payback period ≈ $800,000 / $200,000 = 4 years

You can tune the inputs, but the structure is what matters. Even a $0.01–0.02 gap per bottle becomes meaningful at 8–12 million units per year.

Scenario B – Chemical or OEM plant adding 200 L drum capacity (accumulator)

Now look at a heavier case where an accumulator head usually wins. Assume:

• Annual volume: 250,000 drums of 200 L
• Continuous “work-around” drum weight: 10.0 kg
• Accumulator drum weight (better wall control): 9.2 kg
• Resin price: $1.60/kg
• Scrap on continuous solution: 5%
• Scrap on accumulator head: 2%

Compare the two approaches:

At 250,000 drums per year, just the resin saving is roughly:

$1.79 × 250,000 ≈ $447,500/year

That’s before counting:

• Lower scrap handling and regrind management
• Menos calidad complaints and claims on leaking drums
• Better stacking and transport performance

If the accumulator-head line costs, for example, $500,000 more than a forced continuous workaround, that extra capex is recovered in roughly:

$500,000 / $447,500 ≈ 1.1 years

Even if your actual numbers are less aggressive, it is still realistic to see payback on the incremental capex in 1.5–2.0 years purely from resin and scrap savings on heavy parts.

Energy, carbon and the “hidden line items”

Energy and carbon rarely decide the head type on their own, but they are becoming harder to ignore:

• A difference of 0.02–0.04 kWh/kg looks small on paper, but over thousands of tons and 7–10 years, it becomes a real line on your P&L.
• Unplanned downtime, restart scrap and failed audits add “invisible” cost that doesn’t show in the spec sheet. One hour of stopped blowing can hurt more than 0.01 kWh/kg difference ever will.

On both continuous and accumulator systems, design choices such as barrel insulation, closed-loop parison control, and auto-deflashing have a direct impact on:

• kWh/kg
• Labor per 1,000 units
• Scrap percentage

When you benchmark suppliers, ask for hard data on these three items and not just a “nominal” energy claim.

To see how LEKA thinks about TCO in real machines:

• For energy windows, fast mold changes and closed-loop control, see
  LEKA Extrusion Blow Molding Machines.
• For labor savings and reduced manual trimming, see
  Auto-deflashing Extrusion Blow Molding Machine.

Quality, Risk, and Sustainability Trade-offs

Wall-thickness, defects, and customer complaints

From a business angle, wall-thickness is not a technical detail. It is the difference between clean deliveries and expensive claims.

Uneven walls show up as:

• Leaks on the pallet or inside the container
• Paneling when drums suck in under vacuum or temperature changes
• Handle or corner cracks during transport
• Failed drop tests or stacking tests that block certifications

With a continuous head, the parison hangs for longer, especially on taller or heavier parts. Gravity pulls the melt down, so the bottom can become too thick, while the shoulder or top becomes too thin. You can compensate with parison programming and tuning, but the risk of thin spots remains higher on large parts.

With an accumulator head, the parison is pushed out in one shot, with a shorter hanging time. That gives you tighter control over where the material goes – corners, bottoms, thread areas, handle legs. For 120–220 L drums and larger tanks, that control turns directly into:

• Menos rechazos
• Less rework
• More stable mechanical performance across batches

Every 1–2% drop in defect rate on a high-value, heavy part feeds straight into your margin.

Changeovers, uptime and operator skill

Your ability to make money on a blow molding asset is heavily driven by uptime and planned changeover performance.

On a well-designed continuous extrusion line, you should target mold changes in roughly 60–90 minutes for typical bottle sizes, assuming good SMED discipline and trained staff. That keeps the line flexible enough to follow marketing and seasonal SKUs without eating your OEE.

On accumulator-head lines, tooling is larger and heavier. You may need a crane or gantry, extra safety steps, and more careful cooling and reheating procedures. Changeovers will naturally be less frequent, but each one is a bigger event and needs planning.

This is where operator skill and culture matter. The best plants treat mold change like a pit stop, not an interruption:

“Our best plants treat mold change like a pit stop, not a random event.”

From a CFO or GM perspective, the questions are simple:

• How many planned changeovers per month will we run on this line?
• What is the realistic target time with our people, not just in a demo video?
• What level of training and standard work is the vendor offering?

Continuous systems reward you for fast, frequent changes. Accumulator systems reward you for few, well-planned changes on high-value parts.

Food safety, audits and compliance

If you are in food, beverage, personal care or pharma-adjacent products, you live under a permanent audit spotlight. From that perspective, both head types are judged less on the melt flow concept and more on overall line design.

Typical audit and compliance checkpoints include:

• Inline leak tests and, where needed, burst tests
• Vision systems for flash, short shots, and cosmetic defects
• Clean, well-guarded machine layouts with controlled access
• Traceable recipes and batch reporting

The head type itself does not decide whether you pass a BRC, IFS, or brand audit. What matters is whether the supplier has:

• A clean machine layout
• Integrated testing and inspection options
• Proper documentation, manuals, and training flows

This should be part of your vendor evaluation, right next to energy and cycle-time claims.

PCR, brand pressure and retailer requirements

Retailers and global brands are pushing harder on PCR content and CO₂ per container. For you, that pressure arrives as:

• Minimum % PCR in packaging by a given year
• Requests for LCAs (life cycle assessments)
• New taxes or fees tied to virgin resin use

Both continuous and accumulator systems can be engineered to run 20–50% PCR, sometimes more, but the business risk lies in stability:

• Unstable processing of PCR leads to higher scrap, more downtime, and more complaints.
• Big drums and tanks made with poorly controlled PCR can create significant liability.

The right questions for your supplier are not: “Can you run PCR?” Almost everyone will say yes. The real questions are:

• What PCR percentages have you run on similar containers?
• What were the scrap rates and cycle times at those levels?
• Do you have video or logged data from reference plants?

When you discuss PCR and sustainability, that is a good moment to point your team back to real equipment examples and options, such as:
LEKA Extrusion Blow Molding Machines – PCR-ready configurations.

Comparison Table – Risk & Sustainability View

Use this table as a fast way to align engineering, operations, and finance on the risk profile of each head concept.

For small and medium bottles, the risk-adjusted sweet spot is usually a well-specified continuous line. For large drums and tanks, a correctly engineered accumulator line reduces both technical risk and financial downside per part.

Seen through that lens, quality and sustainability choices are not about being “green” for marketing. They are about reducing unplanned losses, claims, and wasted resin over the entire life of the asset.

Scaling Roadmaps: From First Line to Full Factory

Growth-stage CPG – from zero to three lines

For a growth-stage CPG brand, the question is rarely “Which machine can do everything forever?”. The smarter question is: “What is the lowest-risk path from zero to a stable in-house packaging platform?”

Think in three stages.

Stage 1 – Year 1: One continuous EBM line for your core SKUs

You start with a single continuous extrusion line sized around your main volume SKUs:

• Your top 2–4 bottle sizes (for example 500 ml, 1 L, 3 L)
• The shapes and neck finishes that drive most of your revenue
• The colors and label formats your brand will keep for at least 2–3 years

Financially, this gives you:

• A clear capex figure that fits into one approval cycle
• A direct path to reduce bottle cost by $0.01–0.02 per unit on volumes above 5–10 million units/year
• A way to stabilise supply risk without building a full in-house packaging empire on day one

Operationally, the focus is on getting one line to:

• Run at target OEE (often >80% on core SKUs)
• Hit planned mold change times (ideally <60–90 minutes)
• Lock down stable resin, PCR and color recipes

Stage 2 – Year 2–3: Add the second line for redundancy and growth

Once the first line has a proven track record, line 2 is less experimental and more about risk management and growth capacity. It can:

• Cover overflow on your highest volume SKUs
• Take on new bottle sizes planned in the 2–3 year roadmap
• Provide redundancy so a breakdown does not stop your entire production

From a CFO view, line 2:

• Reduces single-asset risk
• Gives headroom to support new markets or new channels
• Makes it easier to negotiate supplier terms on resin and caps, as your internal volumes are now visible and stable

Stage 3 – Later: Larger-capacity line or partnership for drums/bulk

Only once your core bottle business is stable should you think about:

• A higher-output continuous line for big retail pushes or export
• An accumulator head solution for bulk packs (for example 20–30 L or 60 L plus)
• Strategic partnerships or joint ventures if you enter drums and tanks

The key message: you don’t need to solve everything on day one. You design a phased asset roadmap that matches your SKU roadmap and your balance sheet.

OEM bottle/packaging factories – mixing head types

OEM bottle and industrial packaging factories have a different logic. They live and die by how flexibly they can say “yes” to different RFQs while keeping a clean cost base.

Typical stable mixes look like this:

• Multiple continuous lines dedicated to:
  • Personal care and home-care bottles
  • Agrochem and lube oil bottles up to around 20–30 L
  • Private-label jobs with frequent artwork and minor geometry changes
• One or two accumulator-head lines reserved for:
  • 120–220 L drums
  • IBCs and large tanks above 500 L
  • Special technical parts where shot weight and wall programming drive quality

From a business side, this mix gives you:

• A strong base of repeat bottle contracts with high-speed continuous lines
• The ability to handle high-value, heavy parts at competitive resin and scrap levels
• A portfolio that lets your sales team quote both medium-volume bottles and lower-volume drums/tanks without over-engineering

If you only buy continuous lines, you risk losing all serious drum and tank business. If you only buy accumulators, you tie up capital in over-specified assets making simple bottles. The right balance is usually continuous for throughput, accumulator for heavy margin jobs.

Layout, utilities and shared infrastructure

As you scale, the next bottleneck is not always the machine. It is the building and the servicios wrapped around it.

Key layout and utility questions:

• Power
  • Continuous bottle lines might draw less per machine, but several in parallel add up.
  • An accumulator drum line has a higher peak load because of large drives and heating zones.
• Compressed air
  • High-cavitation bottle lines can consume significant Nm³/h of air.
  • Drums and tanks use more air per shot, but at lower overall shot frequency.
• Cooling water
  • Bottles: more molds and more cycles mean constant cooling demand.
  • Drums/tanks: heavy parts need longer cooling; you must size chillers accordingly.
• Material handling
  • Silos and conveying must handle both virgin and PCR without contamination.
  • Regrind loops from flash and scrap must be designed so they don’t overload specific lines.

On top of that, big accumulator molds and heads often require:

• A crane or gantry with safe working loads well above the heaviest tool
• Clear maintenance zones where tools can be pre-heated or serviced without blocking traffic

Thinking about these early avoids the situation where your first machine is fine, but your second or third forces an expensive rebuild of utilities or building structure.

Digital layer: MES, dashboards, remote service

Once you have more than one or two lines, “walking the floor” stops being enough to manage performance. You need a digital view of the plant.

In practice, that means connecting continuous and accumulator lines into:

• A simple MES or data collection layer
• Dashboards that show:
  • OEE by line
  • kWh/kg by line
  • Scrap % by SKU or by mold
  • Downtime codes and frequency

This lets you:

• See which lines are actually making money, not just running
• Spot bad combinations of resin + mold + settings before they become chronic waste
• Compare vendors on facts, not feelings, over 12–24 months

Remote service and diagnostics then sit on top:

• Faster troubleshooting
• Less travel cost for OEM support
• Quicker software and recipe updates when you add SKUs

For a deeper benchmark-style view on how mature players set up their extrusion blow molding assets, see long-form strategic content such as:
Ultimate Guide to Extrusion Blow Molding Machines – 10 Best Manufacturers for the American Market in 2025.

Decision Checklist and Vendor Questions

Five-minute self-check: which head type fits you?

Before you compare quotes, run a quick 5-minute self-check with your team. The goal is to see which way the decision naturally leans, based on your SKUs, volumes, and risk appetite.

Answer these questions with Yes / No:

1. Are 90% or more of your SKUs below 30 L?
2. Will your main revenue in the next 5 years come from bottles and jerrycans rather than drums or tanks?
3. Are your annual volumes per key SKU above 1–2 million units?
4. Do you expect frequent changeovers because of marketing, artwork, or size changes?
5. Do you not plan to produce 120–220 L drums or 500+ L tanks in the next 3 years?
6. Is your first priority a lower initial capex and a clear 3–5 year payback?

If you answered Yes to most of 1–6, your default should be:

• “Go continuous.”
  • Focus on a continuous extrusion line optimised for bottle and jerrycan throughput.
  • Keep the door open to outsource drums or add an accumulator later if your strategy changes.

Now the opposite angle:

1. Do you already have, or plan to have, 120–220 L drums in your core product offer?
2. Are you targeting UN or other high-spec drums where failure risk is not acceptable?
3. Do you need 500–1,000 L tanks or large technical parts as part of your long-term contracts?
4. Is resin already more than 60–70% of your packaging cost, with heavy parts of 5–30 kg each?
5. Would a 1–2% scrap difference on those parts translate into tens or hundreds of tons of wasted resin over 5–10 years?

If your answers are mostly Yes here, you move into:

• “Go accumulator.”
  • A proper accumulator head becomes mandatory for quality, scrap control, and resin savings.

If you are somewhere in the middle – strong bottle business now, but clear plans for drums in 3–5 years – your logic is:

• “Start continuous, plan accumulator later.”
  • Phase 1–2 continuous lines now.
  • Reserve building, crane and utilities capacity for an accumulator line in phase 2 or 3.

This simple check helps you walk into vendor meetings with a default direction, instead of letting the spec be shaped by whoever talks first.

Vendor comparison matrix

Once you know your likely head type, the next question is which vendor. At this stage, move away from generic brochures and into evidence-based questions.

Use a matrix like the one below for your top 2–3 shortlisted suppliers:

For each row, you want hard numbers or named references, not soft promises.

For example:

• Proven output: target values like X bottles/hour for your 1 L bottle, or Y drums/hour for your 200 L drum, with cycle times, cavity counts, and scrap levels specified.
• kWh/kg: actual data under defined conditions – resin type, bottle/drum weight, and climate.
• Mold-change time: a hot change (same family mold) and a cold change (full tool swap).
• PCR proof: trial data at 20–30% PCR minimum, and ideally more if that is in your roadmap.
• Service response: clear 24–48 hour expectations vs 1–2 weeks.

Fill this table as you meet each vendor. By the end, the strongest option usually reveals itself in the pattern of evidence, not in the most polished brochure.

Red flags for CFOs and founders

During this process, watch for red flags:

• The vendor cannot give specific output numbers for your exact container, only “up to” figures.
• Energy claims are a single kWh/kg number without test conditions or real plant examples.
• On PCR, the only answer you hear is “yes, we can”, with no data table, video, or reference plant.
• Mold-change times are only shown on a single, lightweight demo mold, not on real production tools.
• Service discussions are vague: no clear response time, no local partner, no stock for critical parts.
• Training is treated as a one-off event, not a structured plan with materials and refreshers.
• Nobody from the vendor can talk comfortably about scrap, OEE, or payback – they only talk about machine features.

Each of these points increases your risk of missed payback and unscheduled cost. If you see several of them at once, treat the proposal as high risk, regardless of the initial price.

How LEKA positions itself in this decision

LEKA’s approach is to sit on your side of the table and look at the decision through P&L and growth, not just through kilowatts and cylinders.

From a product scope, LEKA covers roughly 0–2000 L with continuous and accumulator extrusion soluciones de moldeo por soplado:

• Continuo extrusion lines focused on HDPE/PP bottles and jerrycans in the sub-1 L to 30 L range.
• Accumulator-head solutions for 120–220 L drums and larger industrial parts, where resin, scrap and performance risk dominate the business case.

The focus areas are:

• A defined energy window in kWh/kg, with real case data.
• Mold-change concepts aiming for sub-60 minute changeovers on well-prepared jobs.
• PCR-ready designs, with a growing base of references running 20–50% PCR blends.
• A practical view on OEE, scrap, and operator training so the line hits its payback curve in real conditions, not just in simulations.

The philosophy is simple:

“We help you pick what actually fits your product mix and roadmap, even if that means fewer bells and whistles on the spec sheet.”

To see how the portfolio maps against your SKUs and volumes, start here:

• LEKA Extrusion Blow Molding Machines
• Máquina de moldeo por estirado-soplado if PET is in your roadmap.

Summary and Next Steps

Key takeaways in one view

If you’ve read this far, you’re not just curious about technology. You’re deciding how to lock in your packaging cost structure for the next 5–10 years. Here are the key points:

• Head type = cost structure. Choosing between continuous extrusion and an accumulator head is not a technical detail. It sets your long-term resin usage, scrap, energy, labor, and capex payback profile.
• Continuous wins on bottles and jerrycans. If 90%+ of your SKUs are under 30 L, and your main volumes sit in sub-1 L, 1 L, 3 L or 5 L bottles and jerrycans, a well-specified continuous extrusion line is usually the best way to hit high units/hour at a competitive cost per bottle.
• Accumulator is mandatory for drums and tanks. Once you move into 60–80 L and above, especially 120–220 L drums or 500+ L tanks, an accumulator head stops being optional. You need large shot weights, tight wall-thickness control, and low scrap on heavy, high-value parts.
• TCO beats sticker price. A cheaper line that wastes an extra 1–2 g of resin per bottle or 1–2% more scrap on a 10 kg drum is not cheaper over 5–10 years. Look at capex + resin + energy + labor + scrap, not just the initial price.
• SKU roadmap first, machine brochure second. Always start with your SKU list, volumes, and 2–5 year roadmap. The winner is the head concept that matches your product mix and growth plan, not the machine with the most features on a spec sheet.
• Scaling is phased, not all-in. For growth-stage brands, a sensible path is:
  • Year 1: one continuous line for core SKUs.
  • Years 2–3: a second line for redundancy and growth.
  • Later: an accumulator line or partnership if drums and tanks become strategic.
• Proof beats promises. Your safest vendors are the ones who show you real output, kWh/kg, mold-change times, and PCR performance on containers like yours, not just “up to” numbers and generic PCR claims.

If you remember only one sentence…

If you only remember one line from this guide, let it be this:

“Choose the head type around your real product mix and 5-year roadmap, not the cheapest quote on your desk this quarter.”

A quote that looks 5–10% cheaper today can easily cost you hundreds of thousands of dollars in resin, scrap, downtime, and lost flexibility over the life of the asset.

What to do next

Turn this guide into an action plan inside your company with three steps.

Step 1 – Map your SKUs and volumes

Sit down with your commercial and operations team and build one clear view:

• List every current SKU: size, material, shape, annual volume (k/year).
• Mark which 5–10 SKUs drive most of your gross margin.
• Add your 2–3 year roadmap: new sizes, refill packs, drums, tanks, new markets.

This document becomes your internal “truth” when you talk to vendors, lenders, and investors.

Step 2 – Fill in the ROI tables with your numbers

Take the structures from the TCO and ROI section and plug in your own data:

• Your actual resin price ($/kg).
• Your realistic energy tariff ($/kWh).
• Labor cost per shift.
• Expected scrap % with and without PCR.

Even rough numbers are enough to see if you’re talking about $50,000, $200,000, or $400,000+ per year in potential savings. That gives you a clear target payback window for any investment.

If you need to reduce labor per unit at the same time, look at trimming steps such as manual flash cutting. That’s where equipment like
Auto-deflashing Extrusion Blow Molding Machines
can turn manual work into automated, repeatable cost.

Step 3 – Shortlist vendors and ask hard questions

With the self-check and ROI view in hand, you can:

• Decide whether your default is continuous, accumulator, or a phased mix.
• Shortlist 2–3 suppliers whose ranges actually fit that direction.
• Use the vendor comparison matrix in your RFQ process, focusing on:
  • Proven output for your container
  • Documented kWh/kg
  • Real mold-change times
  • PCR data on similar parts
  • Service response and spare parts

If you want a partner who can look at your SKU map, plant layout, and P&L with you, not just send a machine proposal, the next step is simple.

For technical and commercial discussions on extrusion blow molding lines, start here:
Máquinas de moldeo por extrusión-soplado

To speak directly with the team about your bottles, drums, or roadmap, reach out via:
Contact us

Send your key SKUs, target volumes, and rough budget window, and LEKA can help you build a head and line configuration that makes sense for your P&L, not just your plant tour.

Buying Guide FAQ – Objections & Answers

How do I know if I need a continuous head or an accumulator head EBM line?

If most of your SKUs are under 30 L and your money is made on high-volume bottles and jerrycans, you usually start with a continuous extrusion line. It gives you more units per hour, faster changeovers, and a lower entry capex.

If your business depends on 120–220 L drums, large tanks, or any part above 60–80 L where each piece weighs several kilos, you move into accumulator head territory. There, better wall-thickness control and lower scrap on heavy parts will protect your margin more than a small saving on initial price.

If your mix is in between, the typical roadmap is: continuous now, accumulator later, once drums and tanks are truly strategic.

What ROI timeline can I realistically expect if I bring bottles in-house?

For 1 L Botellas de HDPE at volumes above 8–10 million units/year, it is common to see a $0.01–0.02 saving per bottle after you move from buying in to a well-run continuous EBM line.

On 10 million bottles, a $0.02 saving equals roughly $200,000/year. If your full line investment is in the mid-six-figure range, a 3–5 year payback is realistic, depending on your resin price, energy tariff, and labor cost.

The exact number depends on your grams per bottle, scrap %, and kWh/kg, which is why a simple TCO model built around your own data is better than a generic ROI promise.

Why can Leka’s EBM lines be more energy-efficient than other options?

Energy efficiency is not about one magic component. It comes from how the extruder, head, heating, cooling, and controls work together.

Leka focuses on:

• Defined kWh/kg windows measured on real parts, not just in theory
• Barrel and head insulation that reduces heat loss over long shifts
• Closed-loop parison control to cut rework and restart scrap
• Options like auto-deflashing to lower the labor and compressed-air cost per unit

Instead of generic claims, Leka uses measured energy data on parts similar to yours, so you can see how much saving is realistic over 5–10 years.

What is the risk that my scrap and downtime go up when I start using PCR?

PCR adds variation to your process: different melt flows, more gels, sometimes more contamination. If the machine is not designed or tuned for it, you can see higher scrap %, more downtime for cleaning and adjustment, and unstable wall thickness on critical areas.

Leka’s approach is to treat PCR as a process design problem, not a marketing slogan. The team looks at your target PCR %, resin source, and container type, then adjusts screw/barrel design, temperature profiles, and control loops accordingly.

Where possible, Leka also shares trial data and settings from similar jobs, so you have a realistic expectation on scrap and cycle time rather than a blind promise that “PCR is easy”.

What if my product mix changes in 3–5 years? Will I be stuck with the wrong machine?

Your product mix will change. That is normal. The key is to avoid a layout that is locked to a single narrow window.

Leka usually designs projects around:

• A core bottle or drum family that pays for the line
• Clear mold and head options that let you add nearby SKUs later
• A site plan that leaves room for a future accumulator line if drums or tanks grow

Mold-change concepts, clamping force, and head size are chosen so your first machine can reasonably cover a cluster of SKUs, not only one “hero” bottle. The goal is to give you optionality without overspending on day one.

How do I compare Leka against other suppliers in a way my CFO will trust?

The safest way is to compare on evidence, not features. Put each supplier into the same grid and look at:

• Proven output on your bottle/drum size
• Documented kWh/kg with clear test conditions
• Real mold-change times on production tools
• PCR performance at your target percentages
• Service response time and spare-parts stock

Leka is comfortable in that type of comparison because projects are built around TCO and real plant data. If another supplier can beat that on a clear, apples-to-apples comparison and still deliver stable quality, you’ll see it. If not, the numbers will work in Leka’s favor.

What information does Leka need to calculate my cycle time and cost per bottle or drum?

To give you a useful result, Leka needs only a small set of inputs:

• Bottle/drum drawing or 3D file (with weight target if known)
• Material (HDPE, PP, PCR %, any special grade)
• Annual volume and shifts you plan to run
• Your local electricity tariff and an idea of labor cost
• Whether you plan to auto-deflash or trim manually

With these, Leka can estimate cycle time, cavitation, kWh/kg, resin usage, and unit cost, and then show you a simple payback window based on your current buy-in price.

Technical SEO Appendix

FAQ Schema Markup (JSON-LD)

Meta Description

Smart guide to continuous vs accumulator blow molding. Cut resin, energy and scrap costs while choosing the right EBM line for growth.

Global CTA – Free “Cycle Time & Cost Calculation Report”

If you want to move from theory to numbers, the next step is simple. Take one of your key bottles or drums and send Leka the drawing or 3D file, along with your material, annual volume, and current buy-in price.

Leka will turn that into a free Cycle Time & Cost Calculation Report tailored to your project. The report will outline:

• Estimated cycle time and cavitation
• Expected resin usage per part and kWh/kg
• A clear unit cost range for in-house production
• A simple payback view compared with your current supplier price

No generic benchmarks, no vague promises. Just a grounded view of what a continuous or accumulator head line from Leka could do for your bottle or drum, so you and your finance team can decide if this is the right investment now.