What is TROMMELFLEX PUR-HF D12Y11YU11Y: An In-Depth Engineering Analysis of the Halogen-Free PUR Low Voltage Reeling Cable
TROMMELFLEX PUR-HF D12Y11YU11Y-J/O is a flexible 0.6/1 kV low voltage reeling cable for high mechanical stress applications. Its engineering value is not only the voltage rating, but the combination of class 5 flexible plain copper conductors, halogen-free polyester-based insulation, a central textile carrier unit, short-length core lay, PUR inner sheath, open support braiding and black halogen-free flame-retardant polyurethane outer sheath. For port cranes, ship loaders, festoon systems, mobile machines and wet outdoor cable routes, the design targets a rare performance window: 25 N/mm² tensile load, ±50°/m torsional stress, 6×D minimum bending radius, 90°C conductor operation and permanent use in water up to 50 m diving depth.
Definition and engineering role
1. What is TROMMELFLEX PUR-HF D12Y11YU11Y?
TROMMELFLEX PUR-HF D12Y11YU11Y-J/O is a halogen-free polyurethane low voltage reeling cable designed for mobile electrical supply under high mechanical stress. In practical harbour and industrial language, it sits between ordinary flexible power cable and heavy-duty crane reeling cable: it is still a 0.6/1 kV cable, but its mechanical package is built for winding, unwinding, travelling, twisting, festooning, wet outdoor exposure and frequent acceleration cycles.
The product family covers multi-core control cables from 7 to 36 cores, four-core power cables from 1.5 to 35 mm², and five-core power cables from 1.5 to 35 mm². This makes it useful for auxiliary drive supply, spreader systems, lifting equipment, festoon lines, mobile machinery, transfer cars, crane accessories and low voltage reeling systems where the cable is not simply pulled once into place, but repeatedly bent and tensioned throughout its service life.
For port engineers, the keyword is combined mobility resistance. The cable must resist not one failure mode but several at the same time: polyurethane abrasion, twist from imperfect cable guidance, tensile load from reel tension, bending fatigue from repeated winding, flame propagation risk in equipment areas, low-temperature flexibility, and wet route exposure including permanent use in water up to 50 m depth.
Technical thesis
Engineering argument: a low voltage reeling cable should not be specified only by voltage and conductor size. In a moving cable system, the real selection question is whether the construction can survive the mechanical path. TROMMELFLEX PUR-HF D12Y11YU11Y answers that question with a central textile carrier, short lay core geometry, PUR sheathing and open support braid — a structure intended to distribute tensile and torsional stress before it concentrates in the copper conductors or at the sheath surface.
1.1 Application profile decoded for port and industrial engineers
| Application dimension | Published technical feature | Engineering meaning |
|---|---|---|
| Cable category | Flexible low voltage reeling cable | Designed for cable reels, mobile cable carriers and dynamic power/control supply, not only static installation. |
| Voltage class | 0.6/1 kV, max AC 0.7/1.2 kV, max DC 0.9/1.8 kV | Suitable for low voltage drive, auxiliary power, control and mobile machine circuits. |
| Mechanical stress | High mechanical stresses | Appropriate for repeated bending, tension, torsion and travel movement. |
| Reeling speed | No restriction; consult manufacturer beyond 180 m/min | High-speed reel systems should be checked at project level for tension, acceleration and drum geometry. |
| Festoon speed | Up to 180 m/min | Suitable for fast festoon systems on cranes and automated handling equipment. |
| Water duty | Permanent use in water up to 50 m diving depth | Valuable for dockside, wet yard, marine equipment and submerged non-potable water routes. |
| Fire behaviour | Similar to IEC 60332-1 | Designed to resist flame propagation on single cable exposure. |
| Low-temperature operation | -50°C fixed, -40°C fully flexible | Supports winter outdoor handling and cold storage/mobile machinery environments. |
Type code and standards
2. Reading the Designation: TROMMELFLEX PUR-HF D12Y11YU11Y-J/O
The full designation carries both application meaning and material meaning. TROMMELFLEX points to drum and reeling duty; PUR-HF identifies the polyurethane, halogen-free construction; and D12Y11YU11Y-J/O is the detailed type designation used for the cable family. In procurement and engineering documents, the most important elements are the voltage class, conductor count, cross-section and whether the selected version is ordered in the required -J or -O configuration.
| Designation element | Practical reading | Why it matters in specification |
|---|---|---|
| TROMMELFLEX | Reeling / drum-flexible cable family | Indicates suitability for drum winding and dynamic movement rather than fixed wiring only. |
| PUR | Polyurethane sheath system | Supports abrasion resistance, tear resistance and wet outdoor mechanical duty. |
| HF | Halogen-free material package | Reduces corrosive halogen acid gas risk in fire compared with halogenated sheath systems. |
| D12Y11YU11Y | Product type designation | Used to identify the specific construction family in technical and purchasing documents. |
| -J / -O | Ordering version | Confirm the protective-conductor requirement and core identification with the project drawing before order. |
| Core count × cross-section | Example: 4×25, 5×16, 24×2.5 | Defines power capacity, control core count, cable diameter, bending radius, weight and permissible tensile force. |
| Week / year marking | White imprint with production time | Useful for traceability, maintenance inspection and replacement planning. |
2.1 Standards and test references used in the data
| Reference | Where it appears | Engineering significance |
|---|---|---|
| DIN EN 60228 / DIN VDE 0295 | Class 5 plain copper conductor | Defines flexible conductor construction used as the bending-fatigue foundation. |
| DIN VDE 0293-308 | Core identification up to 5 cores | Provides colour identification convention for low-core-count versions. |
| DIN VDE 0298-4 | Current carrying capacity | Reference for nominal ampacity values; the given table is for rubber cables on a surface at 30°C ambient. |
| IEC 60332-1 similar behaviour | Resistance to fire | Single-cable flame propagation behaviour for equipment safety evaluation. |
| HD 22.2 part 3.1 | Flexing test reference for 6×D bending radius | Supports the claimed minimum moving bending radius by dynamic flexing verification. |
Construction analysis
3. Construction Analysis: Class 5 Copper, Polyester-Based Halogen-Free Insulation, PUR Sheath and Support Braid
The cable construction is deliberately compact and mechanical. The conductor system provides flexibility, the core lay controls bending fatigue, the textile carrier and support braid manage tensile and torsional loads, while the PUR sheath package deals with abrasion, tear, flame-retardant and water-exposure requirements.
Why PUR-HF matters
Engineering argument: polyurethane is chosen when the cable route is mechanically aggressive: reels, guide rollers, festoon trolleys, crane structures, wet floors, quay edges and moving machine platforms. Halogen-free PUR adds a safety dimension: the material package avoids the halogen acid gas issue associated with halogenated cable materials, while retaining the abrasion and tear resistance that ordinary low voltage flexible cables often lack in reeling duty.
Electrical and thermal parameters
4. Electrical and Thermal Parameters: 0.6/1 kV, 4 kV Test Voltage, 90°C Conductor Operation
The cable is rated at 0.6/1 kV for low voltage systems. The maximum permissible operating voltage is 0.7/1.2 kV AC and 0.9/1.8 kV DC, with an AC test voltage of 4 kV for 5 minutes. The conductor thermal system allows 90°C continuous conductor operation and 250°C short-circuit conductor temperature.
| Electrical / thermal parameter | Value | Engineering interpretation |
|---|---|---|
| Rated voltage | 0.6/1 kV (600/1000 V) | Low voltage mobile supply, auxiliary drive, control and equipment power circuits. |
| Maximum AC operating voltage | 0.7/1.2 kV | Operating boundary for AC systems. |
| Maximum DC operating voltage | 0.9/1.8 kV | Useful where DC auxiliary or drive-related circuits are used. |
| AC test voltage | 4 kV for 5 minutes | Factory / verification level for insulation integrity. |
| Current carrying capacity | According to DIN VDE 0298-4 | Given ampacity values use the stated reference condition: rubber cables on a surface at 30°C ambient. |
| Maximum conductor temperature | 90°C | Continuous thermal limit of the insulation system. |
| Short-circuit conductor temperature | 250°C | Basis for short-time thermal withstand assessment. |
| Ambient temperature, fixed installation | -50°C to +80°C | Static sections can tolerate very low outdoor temperatures. |
| Ambient temperature, fully flexible operation | -40°C to +80°C | Dynamic movement remains allowed down to -40°C, an important figure for winter port and outdoor machinery duty. |
Electrical selection insight
Engineering argument: for a 0.6/1 kV reeling cable, ampacity is only the first electrical check. Repeated winding changes heat dissipation, adjacent layers on a drum may derate current, and voltage drop becomes relevant on long travel lengths. A correct specification verifies conductor size, load current, duty cycle, voltage drop, cable drum geometry and ambient temperature together.
Mechanical behaviour
5. Mechanical Parameters: 25 N/mm² Tensile Load, ±50°/m Torsion and 6×D Bending Radius
The mechanical headline is unusually strong for a low voltage cable: 25 N/mm² maximum tensile load on the conductor, ±50°/m torsional stress and 6×D minimum bending radius. These three values define the cable’s engineering identity. It is a cable for moving equipment where twisting and bending are not installation accidents but normal working conditions.
| Mechanical parameter | Value | Engineering significance |
|---|---|---|
| Maximum tensile load on conductor | 25 N/mm² | Basis for checking reel tension, cable weight, acceleration and vertical hanging sections. |
| Torsional stress | ±50°/m | Important for reels, imperfect cable guidance, moving machinery and multi-plane travel paths. |
| Minimum bending radius | 6 × D | Compact routing possible; proven by flexing tests according to HD 22.2 part 3.1. |
| Reeling operation speed | No restriction; consult manufacturer beyond 180 m/min | High-speed reels require project confirmation of dynamic forces and drum behaviour. |
| Festoon system speed | Up to 180 m/min | Supports fast crane and handling equipment festoon operation. |
One cable, two mechanical limits
Engineering argument: the permissible tensile force in the dimensional table is not a decorative number. It is the project engineer’s limit for reel tension, hanging cable weight and acceleration shock. The 6×D radius protects bending fatigue, while the ±50°/m torsion value protects against twist accumulation. A cable can meet one of these limits and still fail if the other two are ignored; the three must be checked as one mechanical system.
Chemical and environmental performance
6. Environmental Performance: Halogen-Free, Flame-Retardant, Water-Resistant PUR for Wet Port Duty
The environmental package is built around halogen-free PUR and permanent water suitability. The data states flame behaviour similar to IEC 60332-1, halogen-free flame-retardant inner and outer sheaths, and permanent use in water up to 50 m diving depth, excluding drinking water applications. For port, shipyard and industrial users, this combination is significant because many low voltage flexible cables offer either good flexibility or good water behaviour, but not necessarily both under reeling stress.
| Environmental property | Published feature | Engineering value |
|---|---|---|
| Halogen-free design | PUR-HF material package | Reduces corrosive halogen fire-gas risk in enclosed or equipment-dense areas. |
| Flame behaviour | Similar to IEC 60332-1 | Single-cable flame propagation resistance for machinery safety planning. |
| Water resistance | Permanent use in water up to 50 m depth | Supports wet dockside routes, splash exposure and non-potable submerged operation. |
| Outer sheath | Black, opaque PUR | Wear-resistant surface for reels, rollers and festoon movement. |
| Low temperature | -40°C fully flexible | Maintains moving operation in winter outdoor service. |
| High temperature | +80°C ambient, 90°C conductor | Supports machine-room heat, summer outdoor equipment and loaded conductor operation. |
Dimensional and electrical data
7. Control Cable Range: 7×1.5 to 36×2.5 mm²
The control-cable range is built for signal, auxiliary and control supply circuits that must travel with the moving machine. High-core-count versions use natural-colour cores with black numbers, supporting clean cabinet wiring and troubleshooting.
| Number of cores × cross section | Part number | Conductor diameter max mm | Outer diameter min mm | Outer diameter max mm | Free moving bending radius min mm | Weight ca. kg/km | Permissible tensile force max N | Conductor resistance 20°C max Ω/km | Current carrying capacity A | Short circuit current kA |
|---|---|---|---|---|---|---|---|---|---|---|
| 7×1.5 | — | 1.5 | 12.0 | 13.2 | 79 | 230 | 260 | 13.3 | 23 | 0.21 |
| 12×1.5 | — | 1.5 | 15.5 | 16.7 | 100 | 360 | 450 | 13.3 | 23 | 0.21 |
| 18×1.5 | 20165499 | 1.5 | 16.9 | 18.1 | 109 | 470 | 670 | 13.3 | 23 | 0.21 |
| 24×1.5 | — | 1.5 | 19.0 | 20.2 | 121 | 600 | 900 | 13.3 | 23 | 0.21 |
| 30×1.5 | — | 1.5 | 21.1 | 22.5 | 135 | 750 | 1120 | 13.3 | 23 | 0.21 |
| 7×2.5 | — | 2.0 | 13.5 | 14.7 | 88 | 310 | 430 | 7.98 | 30 | 0.36 |
| 12×2.5 | — | 2.0 | 18.9 | 20.1 | 121 | 550 | 750 | 7.98 | 30 | 0.36 |
| 18×2.5 | — | 2.0 | 19.2 | 20.4 | 122 | 670 | 1120 | 7.98 | 30 | 0.36 |
| 24×2.5 | 20160534 | 2.0 | 21.5 | 22.9 | 137 | 870 | 1500 | 7.98 | 30 | 0.36 |
| 30×2.5 | — | 2.0 | 24.4 | 26.0 | 156 | 1090 | 1870 | 7.98 | 30 | 0.36 |
| 36×2.5 | 20140743 | 2.0 | 27.4 | 29.0 | 174 | 1410 | 2250 | 7.98 | 30 | 0.36 |
8. Four-Core Power Cable Range: 4×1.5 to 4×35 mm²
The four-core power range is commonly relevant where three-phase low voltage power and protective conductor functions are required in a compact reeling or festoon cable. The increasing cross-section quickly increases cable diameter, bending radius, weight and tensile limit, so reel selection must be revised whenever the cross-section changes.
| Number of cores × cross section | Part number | Conductor diameter max mm | Outer diameter min mm | Outer diameter max mm | Free moving bending radius min mm | Weight ca. kg/km | Permissible tensile force max N | Conductor resistance 20°C max Ω/km | Current carrying capacity A | Short circuit current kA |
|---|---|---|---|---|---|---|---|---|---|---|
| 4×1.5 | — | 1.5 | 10.0 | 11.2 | 67 | 150 | 150 | 13.3 | 23 | 0.21 |
| 4×2.5 | — | 2.0 | 11.1 | 12.2 | 74 | 200 | 250 | 7.98 | 30 | 0.36 |
| 4×4 | — | 2.5 | 12.3 | 13.5 | 81 | 280 | 400 | 4.95 | 41 | 0.57 |
| 4×6 | 20161503 | 3.1 | 14.1 | 15.2 | 92 | 370 | 600 | 3.30 | 53 | 0.86 |
| 4×10 | — | 4.1 | 17.4 | 18.6 | 112 | 600 | 1000 | 1.91 | 74 | 1.43 |
| 4×16 | — | 5.1 | 20.0 | 21.4 | 128 | 850 | 1600 | 1.21 | 99 | 2.29 |
| 4×25 | 20149378 | 6.2 | 23.5 | 24.9 | 149 | 1230 | 2500 | 0.78 | 131 | 3.58 |
| 4×35 | 20156715 | 7.8 | 28.5 | 30.2 | 181 | 1760 | 3500 | 0.55 | 162 | 5.01 |
9. Five-Core Power Cable Range: 5×1.5 to 5×35 mm²
The five-core range is relevant for three-phase plus neutral plus protective conductor circuits, auxiliary machinery, drives, hoists and mobile distribution systems where neutral availability must move with the load. Compared with four-core versions of the same cross-section, five-core cables are generally larger and heavier, which directly affects reel diameter, festoon trolley spacing and permissible hanging length.
| Number of cores × cross section | Part number | Conductor diameter max mm | Outer diameter min mm | Outer diameter max mm | Free moving bending radius min mm | Weight ca. kg/km | Permissible tensile force max N | Conductor resistance 20°C max Ω/km | Current carrying capacity A | Short circuit current kA |
|---|---|---|---|---|---|---|---|---|---|---|
| 5×1.5 | — | 1.5 | 10.6 | 11.7 | 71 | 170 | 180 | 13.3 | 23 | 0.21 |
| 5×2.5 | — | 2.0 | 11.8 | 13.0 | 78 | 230 | 310 | 7.98 | 30 | 0.36 |
| 5×4 | — | 2.5 | 13.3 | 14.5 | 87 | 330 | 500 | 4.95 | 41 | 0.57 |
| 5×6 | — | 3.1 | 16.4 | 17.6 | 106 | 480 | 750 | 3.30 | 53 | 0.86 |
| 5×10 | — | 4.1 | 18.7 | 19.9 | 119 | 720 | 1250 | 1.91 | 74 | 1.43 |
| 5×16 | — | 5.1 | 21.7 | 23.0 | 139 | 1030 | 2000 | 1.21 | 99 | 2.29 |
| 5×25 | — | 6.2 | 28.2 | 29.8 | 179 | 1500 | 3120 | 0.78 | 131 | 3.58 |
| 5×35 | — | 7.8 | 31.0 | 33.0 | 198 | 2140 | 4370 | 0.55 | 162 | 5.01 |
Data note for purchasing
The given current-carrying capacities are nominal values for rubber cables laid on a surface at 30°C ambient temperature according to the stated VDE 0298-4 reference. For articles without part number, the values shown are approximate and should be confirmed at order stage.
Comparative engineering
10. Comparative Analysis: PUR-HF Reeling Cable vs Ordinary Flexible Rubber Cable vs PVC Control Cable
In many port and machine projects, the mistake is not undersizing the copper; it is underspecifying the cable construction. A static low voltage flexible cable may pass the electrical calculation but fail mechanically on a reel, especially when it sees abrasion, twist, water and repeated bending. The table below frames the decision from an engineer’s point of view.
| Criterion | Generic PVC control cable | General flexible rubber cable | TROMMELFLEX PUR-HF D12Y11YU11Y |
|---|---|---|---|
| Primary duty | Fixed or limited movement | Flexible supply and general industrial use | High mechanical stress reeling and festoon duty |
| Sheath material concept | PVC, typically halogenated | Rubber-based | Halogen-free flame-retardant PUR |
| Abrasion / tear behaviour | Limited under dragging and roller contact | Good in many industrial environments | High, due to polyurethane outer sheath |
| Torsion rating | Usually not the design focus | Depends on construction | ±50°/m stated torsional stress |
| Minimum moving radius | Often too large or not validated for reeling | Application-dependent | 6×D, proved by flexing tests |
| Water service | Usually limited | Depends on compound | Permanent use in water up to 50 m, non-drinking water |
| Fire-gas strategy | Halogen acid gas risk in fire | Depends on rubber compound | Halogen-free material package |
| Best-fit applications | Panels, fixed trays, simple machinery | General outdoor and mobile power | Reels, festoons, cranes, wet port machinery and high-wear mobile systems |
10.1 Reeling vs festoon: the same cable, different stress profile
| System type | Dominant mechanical stress | Relevant cable data | Engineering check |
|---|---|---|---|
| Motorized cable reel | Continuous bending on drum, reel tension, acceleration, possible torsion | 6×D radius, 25 N/mm² tensile, ±50°/m torsion, no speed restriction with consultation beyond 180 m/min | Check drum diameter, tension control, cable layering, fleet angle and acceleration peaks. |
| Festoon system | Repeated loop bending, trolley acceleration and hanging loop weight | Festoon speed up to 180 m/min, 6×D radius, cable weight and tensile limit | Check trolley spacing, loop depth, clamp design, acceleration and minimum loop radius. |
| Wet mobile route | Mechanical wear plus water exposure | Permanent water use up to 50 m; PUR outer sheath | Check non-drinking water condition, sealing, terminations, connectors and water migration risk at cable ends. |
Honest limitation
Engineering argument: a cable suitable for permanent use in water is not automatically a complete underwater electrical system. The cable body may be rated for water exposure, but terminations, glands, connectors, junction boxes and repair joints must be selected to the same environmental standard. In failures described as “water cable failures”, the root cause is often not the sheath but the cable end.
Selection framework
11. How to Select TROMMELFLEX PUR-HF D12Y11YU11Y for a Port, Crane or Mobile Machine Project
Selection should be done as a system calculation, not a catalogue lookup. The correct cable size is the one that satisfies electrical load, voltage drop, bending radius, tensile force, torsion, travel speed, wet environment and flame-safety requirements simultaneously.
| Selection dimension | Data to confirm | Decision it drives |
|---|---|---|
| Circuit function | Control, four-core power or five-core power | Selects the correct range: 7–36 cores, 4-core or 5-core design. |
| Voltage system | 0.6/1 kV AC or relevant DC operating voltage | Confirms compatibility with rated and maximum permissible operating voltage. |
| Load current | Continuous current, duty cycle, ambient temperature and installation condition | Selects cross-section and checks VDE 0298-4 current-carrying capacity. |
| Voltage drop | Travel length, reel length, conductor resistance and starting current | May require a larger cross-section than ampacity alone suggests. |
| Reel or festoon geometry | Drum diameter, trolley spacing, loop depth, roller diameter | Must respect the 6×D minimum bending radius. |
| Tensile load | Cable self-weight, hanging length, acceleration, reel tension | Checked against the listed permissible tensile force for the selected size. |
| Torsion | Cable guidance, multi-plane route, swivel behaviour, reel alignment | Checked against ±50°/m torsional stress. |
| Speed | Reeling speed and festoon speed | Festoon up to 180 m/min; consult manufacturer for reeling beyond 180 m/min. |
| Water exposure | Splash, wet floors, immersion depth, terminations | Confirms suitability for permanent non-drinking water use up to 50 m and compatible end sealing. |
| Fire and material policy | Halogen-free requirement, flame propagation requirement | Supports PUR-HF selection for safer equipment and infrastructure areas. |
Engineer FAQ
12. Frequently Asked Engineering Questions
Question 1 — What is TROMMELFLEX PUR-HF D12Y11YU11Y-J/O?
Answer: It is a flexible 0.6/1 kV halogen-free polyurethane low voltage reeling cable for high mechanical stress applications. It is available as multi-core control cable and as four-core or five-core power cable, with class 5 plain copper conductors, polyester-based halogen-free insulation, central textile carrier, PUR inner sheath, support braid and black flame-retardant PUR outer sheath.
Question 2 — Why use PUR-HF instead of an ordinary flexible cable?
Answer: PUR-HF provides the mechanical and safety package required by reeling and festoon systems: abrasion-resistant polyurethane sheathing, halogen-free flame-retardant materials, 25 N/mm² tensile capability, ±50°/m torsion and 6×D minimum bending radius. Ordinary flexible cables may be electrically acceptable but mechanically unsuitable for repeated winding and twisting.
Question 3 — Is the cable suitable for water immersion?
Answer: Yes. The data states permanent use in water, excluding drinking water, up to 50 m diving depth. In real projects, this must be paired with compatible waterproof terminations, glands and junction boxes; the cable body rating does not automatically protect poorly sealed cable ends.
Question 4 — What bending radius should be used?
Answer: The minimum bending radius is 6×D, using the cable outer diameter D. The published table already lists the minimum free-moving bending radius for each size. Drum cores, rollers, festoon loops and guide sheaves should be checked against that value.
Question 5 — What is the maximum travel speed?
Answer: For reeling operation, the data states no restriction, but for speeds beyond 180 m/min the manufacturer should be consulted. For festoon systems, the stated limit is up to 180 m/min.
Question 6 — How do I choose between 4-core and 5-core power versions?
Answer: Use the project circuit design. Four-core versions suit many three-phase power arrangements, while five-core versions are used where a neutral conductor is required in addition to the phase and protective conductor arrangement. The five-core version is larger and heavier at the same cross-section, so reel or festoon geometry must be checked again.
Question 7 — Why is the central textile carrier important?
Answer: The central textile carrier helps stabilize the core assembly under tension and bending. Together with the short lay and support braid, it prevents the conductors from becoming the sole load-bearing elements during reeling, acceleration and torsion.
Feichun Engineering View
TROMMELFLEX PUR-HF D12Y11YU11Y-J/O represents a practical low voltage solution for moving equipment where electrical selection and mechanical survival must be engineered together. Its 0.6/1 kV rating, 4 kV / 5 min test voltage, 90°C conductor limit, class 5 plain copper conductors, halogen-free polyester-based insulation, central textile carrier, short lay core arrangement, PUR inner sheath, open support braid and black halogen-free flame-retardant PUR outer sheath make it especially relevant for port cranes, festoon systems, reels, shipyard machinery, wet industrial routes and mobile equipment exposed to abrasion, torsion and water. The decisive project checks are not only conductor cross-section and current: they are 6×D bending radius, permissible tensile force, ±50°/m torsion, cable weight, travel speed, low-temperature flexibility, fire behaviour and water-resistant termination design.
