The EP-CWB-2L is the most logistics-intensive machine in the Watanabe مجموعة آلات البطاطس — it changes not just how potatoes are harvested but how they are packaged, handled, transported, and presented to buyers. While the حفارة البطاطس EP-AWB-1600 delivers harvested potatoes into bulk trailers for loose transport, the EP-CWB-2L fills FIBC (Flexible Intermediate Bulk Container) bags of 500 Kg directly from the field — producing self-contained, weighed, and handleable units that can go directly from harvest to fork-lift to cold storage to truck to buyer without bulk transfer.
This guide covers the EP-CWB-2L’s confirmed specification, the operational logistics of big bag harvest management in Korean highland conditions, the integrated grading system that allows the EP-CWB-2L to separate stone fragments and clod material from tubers before bag filling, the stone clearing implications for the grading mechanism’s performance, and the farm operation profiles for which the big bag system is the correct harvest choice versus the bulk elevator system of the EP-AWB-1600 Kit B.
EP-CWB-2L Confirmed Specifications
جميع المواصفات مأخوذة من كتيب منتجات واتانابي الرسمي.
How the Big Bag System Works — From Share to Filled FIBC
The EP-CWB-2L’s operational sequence differs fundamentally from the EP-AWB-1600’s bulk elevator system. Understanding the sequence explains why big bag harvest is slower in terms of forward speed but faster in terms of end-to-end logistics from field to market:
Big Bag vs Bulk Elevator — When Each System Makes Sense
| الأبعاد | EP-CWB-2L (Big Bag) | EP-AWB-1600 Kit B (Bulk Elevator) |
|---|---|---|
| Collection format | 500 Kg FIBC bags — discrete, weighable, fork-liftable | Continuous bulk flow into tractor trailer |
| In-field grading | Yes — stones, clods, and undersized removed before filling | Web separation only — no in-field size grading |
| Post-harvest handling steps | Minimal — bag goes direct from field to cold storage to market | Multiple: trailer to reception bay to grader to pack line to bags |
| خطر الإصابة بالكدمات | Higher per transfer stage (bag drop, fork-lift) | Distributed across multiple handling points |
| Best market channel | Direct market, export, supermarket chain supply (high-presentation) | Cooperative wholesale, processing supply, bulk commodity |
| متطلبات إزالة الأحجار | Strictest — grader efficiency degrades rapidly with high stone load | Zero-tolerance standard (same for all potato harvest machines) |
| Labour at harvest | 1 tractor + 1 fork-lift (or telehandler) for bag exchange | 1 tractor + 1–2 collection trailers + additional tractor for exchange |
The Integrated Grading System — How Stone Clearing Directly Affects Grader Performance
The integrated grading system in the EP-CWB-2L is the component that makes big bag direct market supply viable — it removes residual stones, soil clods, and undersized tubers from the bag fill stream before the bag is closed and dispatched to market. Without this in-field grading step, every 500 Kg bag would require a subsequent grading pass before sale. The grading system’s performance is critically dependent on the input material it receives from the web separator — and therefore directly dependent on the stone clearing quality from Steps 1 and 2:
On stone-cleared fields
The grader receives a stream dominated by tubers and fine soil particles with minimal stone fragments. The grading mechanism can operate at the density threshold calibrated for tuber vs stone separation without being overwhelmed by material volume. Stone rejection rate is low (few stones to reject), grader through-flow is fast, and bag fill rate matches the designed operating capacity. The bag contents when full are clean, well-graded tubers that meet direct market presentation standards without further handling.
On un-cleared fields
High stone content entering the grader overwhelms the separation mechanism — stones that should be rejected accumulate in the grader zone and must be manually cleared during operation stoppages. Stone-contaminated bags (where the grader has been overwhelmed and stones pass through to the fill stream) cannot be sent to direct market — each bag must be manually inspected and re-graded. The practical consequence is that the EP-CWB-2L’s key advantage (direct field-to-market without re-handling) is negated on un-cleared fields. The machine becomes an expensive harvester without its primary operational benefit.
FIBC Bag Logistics — Planning the Headland Rotation System
At 500 Kg per bag and a typical Korean highland yield of 30 t/ha, the EP-CWB-2L fills 60 bags per hectare harvested. On a 5 ha harvest day, 300 bags must be filled, exchanged, and staged at the headland. Planning the bag rotation system before harvest begins is essential for preventing the headland from becoming the operational bottleneck that stops the harvesting pass:
Equipment needed:
One fork-lift, telehandler, or tractor-mounted front fork with minimum 600 Kg lifting capacity. The fork must be able to access the headland bag staging area quickly enough to exchange bags within the harvesting tractor’s typical 3–5 minute headland turn and bag exchange window. A bag exchange that takes longer than the headland turn time means the harvesting tractor waits — every minute of harvesting tractor wait at headland reduces daily coverage.
Staging area requirements:
The headland staging area must accommodate the day’s filled bag accumulation (up to 300 bags × 0.81 m² footprint each = 240 m² of bag footprint on pallets) plus access lanes for the fork-lift. For farms harvesting over multiple days, filled bags from Day 1 must be transported to cold storage before Day 2 harvest reaches capacity at the headland. Planning cold storage transport scheduling to match the daily bag fill rate prevents staging area overflow.
Empty bag pre-staging:
Pre-stage a day’s supply of empty FIBC bags at the headland before harvest begins — not in a single pile requiring fork-lift movement during harvest. Arrange empty bags in sets of 5–10 at each headland access point, accessible to the harvesting tractor operator for quick exchange without fork-lift involvement for each individual bag. Empty FIBC bags weigh only 3–5 Kg each and can be handled manually for the bag mounting step.
Which Korean Operations Suit the Big Bag System
The EP-CWB-2L is not the correct harvest machine for every Korean potato operation. Four operation types represent its strongest business case in Korea:
✓
Direct supermarket or premium retail supply chain. Korean supermarket chains (E-Mart, Lotte Mart, Homeplus) increasingly source highland potato in FIBC or FIBC-equivalent units for in-store weighing and packing from the field unit rather than bulk-transferred commodity. The EP-CWB-2L’s in-field grading and 500 Kg bag format matches this direct supply format. Farms supplying premium direct channels where the price premium over cooperative supply justifies the additional harvester investment are the primary Korean big bag market.
✓
Export supply operations. Korean fresh potato export (primarily to Japan and Southeast Asia) requires consistent pack weights, clean product, and minimal post-harvest handling steps that could introduce contamination or bruising. The EP-CWB-2L’s graded, weighed, sealed FIBC bag from field is the preferred format for export assembly operations — the importer receives a known-weight, known-grade product unit without re-processing.
✓
Cold storage operations without grading line infrastructure. Korean highland farms with cold storage facilities but without a separate mechanical grading line can use the EP-CWB-2L’s in-field grading to eliminate the need for a post-harvest grading installation. The bag goes directly from field to cold storage rack — bypassing the grading step that would otherwise require a separate facility investment.
✗
Not suitable: cooperative bulk supply or processing contract supply. Cooperatives and crisp manufacturers receive bulk-delivered potato at fixed farm prices — the big bag format adds cost and complexity without adding value to buyers who have their own receiving, grading, and processing infrastructure. For these supply channels, the EP-AWB-1600 with Kit B bulk elevator into trailer is the correct and lower-cost harvest system.
EP-CWB-2L Maintenance — Grader System Attention
The EP-CWB-2L’s grading system requires specific maintenance attention beyond the standard share, web, and bearing service that applies to all potato harvesters. The grading mechanism is exposed to a constant flow of soil, tuber skin, and small stone fragments — materials that accumulate on the grading surfaces and progressively degrade separation accuracy if not cleaned regularly:
| فاصلة | مهمة | Sign of neglect |
|---|---|---|
| After each harvest day | Pressure wash all grader surfaces (star rollers or gap separators). Remove any soil or tuber skin build-up from separation gaps. Inspect grader gap settings for uniform spacing. | Stones passing through to the fill stream; small tubers being rejected when they should pass; slow grader flow rate from buildup resistance |
| Weekly during harvest | Lubricate all grader roller bearings; check roller rotation for any binding; confirm bag mounting frame integrity (handles daily load cycles of 500 Kg) | Squealing grader rollers; bag frame deformation under repeated 500 Kg loading |
| Post-season storage | Full grader disassembly clean; lubricate all bearing points; check all roller surfaces for wear or damage; document gap settings for next season setup | Corrosion in gap separators during storage season reduces grading accuracy in the following season’s first bags |
الأسئلة الشائعة
How many FIBC bags does the EP-CWB-2L fill per hour at typical Korean highland potato yield?
At 30 t/ha yield, 500 Kg bags, and 1.5–2.0 km/h harvesting speed with 70 cm row spacing (2-row = 1.40 m working width): the EP-CWB-2L covers approximately 0.21 ha/hr at 1.8 km/h, producing approximately 0.21 ha × 30 t/ha = 6.3 tonnes/hr = 12–13 bags per hour of actual harvesting time. With headland exchanges and travel, the effective daily bag fill rate (7 productive hours) is approximately 70–85 bags per day — equivalent to 35–42 tonnes of potato. This is approximately 1.2–1.4 ha/day effective harvest coverage for the EP-CWB-2L, which is lower than the EP-AWB-1600’s 3–5 ha/day. The lower coverage rate is the trade-off for the in-field grading and direct bag format — justified only where the downstream logistics advantage of the pre-graded big bag format generates economic return that exceeds the coverage rate difference.
Can the FIBC bags from the EP-CWB-2L be stored directly in standard cold storage without additional packaging?
Yes — the 500 Kg FIBC bag is the storage unit as well as the harvest unit. Bags placed on pallets in cold storage at 3–5°C for fresh market or 8–10°C for Atlantic processing allow air circulation through the FIBC fabric (which is woven rather than film-sealed). This breathable storage prevents the condensation accumulation that occurs in film-sealed containers. For extended Dubaek storage (6 months at 3°C targeting the February market), the FIBC’s breathable fabric allows the respiration gases (CO₂ and moisture) produced by the living tubers to escape rather than accumulating inside the bag and accelerating dormancy break. One management check required during extended FIBC bag storage: inspect the bag base for any accumulation of leaked soil or condensate that could create soft rot conditions at the bag base contact area — replace any bag showing base contamination within 72 hours of detection.
What is the minimum stone clearing standard for the EP-CWB-2L grader to function correctly?
The EP-CWB-2L grader is designed to handle occasional residual stones below 3 cm that pass the web separator — stones at this size are manageable within the grader’s rejection capacity without overloading the separation mechanism. The grader is not designed to handle regular stone volumes from inadequately cleared fields where stones above 5 cm remain in the soil profile. For EP-CWB-2L operations, the ثور 2.4 + CT-2100 zero-tolerance stone clearing standard (below 3 cm residual) should be treated as a minimum requirement rather than a quality aspiration — because the grader’s performance is calibrated to this input condition. Fields that have not been cleared to zero-tolerance standard should use the EP-AWB-1600 bulk system rather than the EP-CWB-2L big bag system until clearing is brought to standard.
Is the EP-CWB-2L eligible for Korean agricultural machinery subsidies?
Yes — the EP-CWB-2L qualifies under the Korean agricultural machinery purchase support program in the specialty crop machinery category (potato harvesting machinery), the same category as the EP-AWB-1600. Korea Watanabe holds Korean agricultural machinery certification for the EP-CWB-2L and prepares full subsidy documentation at no charge. Because the EP-CWB-2L is a more specialised machine than the EP-AWB-1600, confirm current year certification status with Korea Watanabe in December before the January application window to ensure the most current certification document is prepared for submission.
Can a farm operate both the EP-CWB-2L and EP-AWB-1600 on different field sections in the same harvest season?
Yes — and this is a practical approach for farms supplying to multiple market channels simultaneously. The EP-CWB-2L harvests the field sections designated for premium direct market or export supply (where the big bag format adds value). The EP-AWB-1600 harvests sections designated for cooperative bulk supply or processing contract (where bulk trailer delivery is the correct format). Both machines use the same 75 HP minimum tractor requirement and the same row spacing (confirmed at the furrowing step). On a single-tractor farm, the two machines cannot operate simultaneously — but the seasonal scheduling can alternate: EP-CWB-2L on the high-value sections first (premium market supply is time-sensitive for early-season pricing), then EP-AWB-1600 for the bulk supply sections that have a longer delivery window. Two-tractor farms can operate both machines simultaneously on separate field sections for maximum harvest rate.
EP-CWB-2L vs EP-AWB-1600 — System Recommendation for Your Market Channel
Market channel (cooperative / direct / export) + field area (ha) + existing cold storage format → big bag vs bulk elevator recommendation with stone clearing standard requirement. Korea Watanabe, Ansan-si, Gyeonggi-do.
المحرر: Cxm
