Flexible couplings N-EUPEX and N-EUPEX DS series

N-EUPEX as overload-holding, fail-safe series

N-EUPEX DS as overload-shedding, non-fail-safe series

N-EUPEX and N-EUPEX DS claw couplings connect machines. They compensate for shaft misalignment, generating only low restorative forces.

The torque is conducted through elastomer flexibles, so the coupling has typically flexible rubber properties.

N-EUPEX couplings are overload-holding. By contrast, the N-EUPEX DS series is designed so that overload or advanced wear causes irreparable damage to the elastomer flexibles. The metal parts of N-EUPEX DS couplings can then rotate freely against one another without contact.

Elastomer flexible of the N-EUPEX series

The flexibles of the N-EUPEX coupling are subjected to compression. If the flexibles are irreparably damaged, the hub parts come into contact with metal. This “emergency operation capability” is required, e.g., in the case of fire pump drives.

Elastomer flexible of the N-EUPEX DS series

The flexibles of the N-EUPEX DS series are subjected to compression and bending forces. If the flexibles are irreparably damaged, the metal parts turn against one another without contact, and the power transmission is separated. Fitting new flexibles will make the coupling once more usable.

The capacity of the N-EUPEX DS series to shed overloads is especially in demand for highly sensitive machines.

Область применения

The N-EUPEX coupling is available as a catalog standard in 23 sizes with a rated torque of between 19 Nm and 62000 Nm. The coupling is suitable for use at ambient temperatures of between –30 °C and +80 °C. By using alternative elastomer buffers, the permissible ambient temperature range can be extended to between –50 °C and +100 °C.

Frequently, the coupling is used to connect the motor to the gear unit input shaft. The coupling is suitable especially for drives with uniform to average dynamic loads. Examples of applications are pump drives, ventilator drives or crane running gear. Furthermore, N-EUPEX couplings can be used as add-on couplings, particularly on FLUDEX fluid couplings or ARPEX AKR safety couplings. In the case of drives with a diesel engine, N-EUPEX couplings are suitable for driven machines with a low mass moment of inertia.

In the case of diesel engine drives, the actual dynamic coupling load should be checked by measurement or torsional vibration calculations.

Coupling suitable for potentially explosive environments. Complies with Directive 94/9/EC for:

II 2 G T4 / T5 / T6 D120 °C

–30 °C ≤ T_a ≤ +80 °C / +50 °C / +40 °C

I M2

Дизайн

N-EUPEX and N-EUPEX DS couplings consist of two hub parts mounted on the machine shafts. The coupling parts are connected positively by means of elastomer flexibles. On the twopart variant, the elastomer flexibles can be changed only if one of the coupled machines is moved. On the three-part variants, the bolted cam ring can be released and moved to enable the flexible to be changed without moving the coupled machines.

Materials

Cam parts, pocket parts, adapters and hubs

Grey cast iron EN-GJL-250

Flexible materials

N-EUPEX Series

Material/description	Hardness	Identification	Ambient temperature
NBR standard type	80 Shore A	Flexible black with blue stripe	–30 °C … +80 °C
NBR soft	65 Shore A	Flexible black with green stripe	–30 °C … +80 °C
NBR hard	90 Shore A	Flexible black with magenta stripe	–30 °C … +80 °C
NBR normal low backlash	80 Shore A	Flexible black with yellow stripe	–30 °C … +80 °C
NBR soft low backlash	65 Shore A	Flexible black with white stripe	–30 °C … +80 °C
NR for low temperature	80 Shore A	Flexible black with orange stripe	–50 °C … +50 °C
HNBR high temperature	80 Shore A	Flexible black with red stripe	–10 °C … +100 °C

N-EUPEX DS Series

Material/description	Hardness	Identification	Ambient temperature
NBR compound flexibles for size 66 … 272	80/90 ShoreA 2 components	Flexible black	–30 °C … +80 °C
NBR hard for size 305 ... 556	90 Shore A	Flexible black	–30 °C … +80 °C
PU electrically insulating	95 Shore A	Flexible blue	–30 °C … +50 °C

PU elastomer flexibles in special design on request.

The technical data and the product codes do not include the flexible variants NBR low backlash, HNBR high temperature and
NR low temperature and the DS flexibles polyurethane electrically insulating.

Technical data, prices and product codes on request.

Brake disks

EN-GJS-400 spheroidal graphite cast iron or S355J2G3 steel

Brake drums

Grey cast iron EN-GJL-250

Low-temperature application

Shock loads in the drive caused by e.g. starting of drives with large masses to be accelerated (e.g. in fan drives) result in high component loads, particularly at low temperatures.
For such applications a particularly robust coupling series must be selected. Of the flexible couplings, the RUPEX pin-and-bush coupling is especially suited for this.

Types of N-EUPEX claw coupling

Type	Description
A	Fail-safe, 3-part
B	Fail-safe, 2-part
D	Fail-safe. 3-part, flange variant
E	Fail-safe. 2-part, flange variant
H	Fail-safe, with adapter
O	Fail-safe, 2-part, with brake drum
P	Fail-safe, 3-part, with brake drum
EBD	Fail-safe, 2-part, with brake disk
DBD	Fail-safe, 3-part, with brake disk
DBDR	Fail-safe, 3-part, with brake disk, brake disk radially dismountable
ADS	Non-fail-safe, 3-part
BDS	Non-fail-safe, 2-part
HDS	Non-fail-safe, with adapter

Further application-related coupling types are available. Dimension sheets for and information on these are available on request.

Types of N-EUPEX claw coupling on request

Type	Description
AT	Fail-safe, 3-part, with Taper clamping bush
BT	Fail-safe, 2-part, with Taper clamping bush
G	Fail-safe, 2-part, with intermediate shaft
F	Fail-safe, 3-part, with intermediate shaft
K	Fail-safe, 3-part, with brake drum to customer's requirement
L	Fail-safe, 2-part, with brake drum to customer's requirement
M	Fail-safe, 2-part, with flange dimensions to SAE J620d

Modular principle of N-EUPEX types

Types A and ADS

Types B and BDS

Type D

Type E

Type P

Type O

Type DBDR

Type DBD

Type EBD

Types H and HDS

Further application-related coupling types are available. Dimension sheets for and information on these are available on request.

Функции

The motor torque is transmitted to the hub at the drive end via the shaft-hub connection, which is mostly designed as a keyway connection. The torque is transmitted to the hub on the output side with the aid of elastomer flexibles. The hub on the output side further transmits the torque to the driven machine or a gear unit placed in between. Because of the primarily compressionloaded elastomer flexibles, the coupling has a progressive torsional stiffness.

In the case of the N-EUPEX DS coupling series, the elastomer flexible is subjected to bending and compression loads. In the event of overload or advanced wear, the coupling disconnects positively and the flexibles are irreparably damaged. The metal parts then rotate without touching one another. After new elastomer flexibles are fitted, the N-EUPEX DS coupling is once more operable.

N-EUPEX DS couplings are maintenance-free, even in potentially explosive environments, so long as the possible torque interruption does not lead to an unacceptable disruption of the production process.

Особенности

N-EUPEX couplings are designed on the modular principle and have a very simple construction. N-EUPEX types are made up of subassemblies to suit requirements. The couplings are assembled by simply fitting the coupling halves together. Wear is restricted to the elastomer flexibles, which must be replaced at the end of their service life.
Depending on type, the elastomer flexibles can be changed without moving the coupled machines.
The coupling parts are readily available from stock and are mostly finish-machined, i.e. with finished bore, keyway, set screw and balancing.

Optionally:

The wear indicator for N-EUPEX couplings enables the condition of the flexible to be easily assessed. The wear condition can also be ascertained with the aid of a stroboscope while the coupling is rotating. The production process can thus continue undisturbed.

If the stroboscope is to be used in a potentially explosive environment, you can enquire about the equipment for this at FLENDER.

The wear indicator must be attached to the outside diameter of the coupling after the coupling has been fitted.

Технические данные

Power ratings of the N-EUPEX series

Size	Rated torque for flexible type			Torsional stiffness at 50 % capcity utilization for flexible type			Assembly	Permitted shaft alignment at n = 1500 rpm ¹⁾
	65 ShoreA	80 ShoreA	90 ShoreA	65 ShoreA	80 ShoreA	90 ShoreA	Gap dimension ²⁾	Axial	Radial	Angle
	T_KN	T_KN	T_KN	C_{Tdyn 50 %}	C_{Tdyn 50 %}	C_{Tdyn 50 %}	ΔS	ΔK_a	ΔK_r	ΔK_w
	Nm	Nm	Nm	kNm/rad	kNm/rad	kNm/rad	mm	mm	mm	°
58	11	19	19	0.21	0.50	0.93	1.0	0.2	0.2	0.15
68	21	34	34	0.39	0.90	1.80	1.0	0.2	0.2	0.15
80	37	60	60	1.05	2.40	4.50	1.0	0.2	0.2	0.12
95	63	100	100	1.64	4.00	7.40	1.0	0.2	0.2	0.12
110	100	160	160	2.49	6.00	11.40	1.0	0.2	0.2	0.10
125	150	240	240	3.70	9.00	17	1.0	0.25	0.25	0.10
140	230	360	360	5.60	13.2	25	1.0	0.25	0.25	0.10
160	350	560	560	11.2	26.7	51	2.0	0.3	0.3	0.10
180	550	880	880	19.2	46	88	2.0	0.3	0.3	0.10
200	850	1340	1340	31.6	75	139	2.0	0.3	0.3	0.09
225	1260	2000	2000	48	115	212	2.0	0.35	0.35	0.09
250	1760	2800	2800	68	162	302	2.5	0.35	0.35	0.08
280	2460	3900	3900	95	226	420	2.5	0.4	0.4	0.08
315	3500	5500	5500	171	370	730	2.5	0.4	0.4	0.08
350	4850	7700	7700	235	520	950	2.5	0.5	0.5	0.08
400	6500	10300	10300	316	750	1420	2.5	0.5	0.5	0.08
440	8500	13500	13500	390	930	1920	2.5	0.6	0.6	0.08
480	10500	16600	16600	510	1200	2300	2.5	0.6	0.6	0.07
520	13300	21200	21200	600	1410	2710	2.5	0.65	0.65	0.07
560	18300	29000	29000	1000	2340	4400	3.0	0.65	0.65	0.07
610	24000	38000	38000	1300	3030	5700	3.0	0.75	0.75	0.07
660	30900	49000	49000	1640	3800	7100	3.0	0.8	0.8	0.07
710	39000	62000	62000	2140	4900	9100	3.0	0.9	0.9	0.07

¹⁾ The maximum speed of the respective type must be noted. For further information on permissible shaft misalignment, please see the operating instructions.

²⁾Does not apply to type H.

For maximum coupling torque: T_Kmax = 3.0 · T_KN

For coupling overload torque: T_KOL = 3.5 · T_KN

For coupling fatique torque: T_KW = 0.15 · T_KN, where T_N > T_W must be adhered to.

Torsional stiffness and damping

The values stated in the above table apply to a capacity utilization of 50 %, an excitation amplitude of 10 % T_KN with the frequency 10 Hz and an ambient temperature of 20 °C. Dynamic torsional stiffness is dependent on load and increases in proportion to capacity utilization. The following table shows the correction factors for different nominal loads.

C_Tdyn = C_{Tdyn 50 %} · FKC

	Capacity utilization T_N/T_KN
	20 %	40 %	50 %	60 %	70 %	80 %	100 %
Correction factor FKC 65/80/90 ShoreA	0.54	0.84	1.00	1.18	1.36	1.55	1.97

The damping coefficient is Ψ = 1.4

Furthermore, torsional stiffness and damping depend on the ambient temperature and the frequency and amplitude of the torsional vibration excitation. More precise torsional stiffness and damping parameters on request

Permitted shaft misalignment

The permitted shaft misalignment depends on the operating speed. As the speed increases, lower shaft misalignment values are permitted. The following table shows the correction factors for different speeds.
The maximum speed for the respective coupling size must be observed!

ΔK_perm = ΔK₁₅₀₀ · FKV

	Speed in rpm
	500	1000	1500	3000
Correction factor FKV	1.7	1.2	1.0	0.70

The axial misalignment may occur dynamically at frequencies up to 10 Hz. For fitting a maximum gap dimension of S_max = S + ΔS and a minimum gap dimension of S_min = S – ΔS is permitted. Shaft misalignments ΔK_a, ΔK_r and ΔK_w may occur simultaneously.

Power ratings of the N-EUPEX DS series

Size	Rated torque	Torsional stiffness at 50 % capcity utilization	Assembly	Permitted shaft misalignment at speed n = 1500 rpm
			Gap dimension ¹⁾	Axial	Radial	Angel
	T_KN	C_Tdyn	ΔS	ΔK_a	ΔK_r	ΔK_w
	Nm	kNm/rad	mm	mm	mm	°
66	19	0.73	1.0	0.2	0.2	0.15
76	34	1.36	1.0	0.2	0.2	0.15
88	60	2.62	1.0	0.2	0.2	0.12
103	100	4.00	1.0	0.2	0.2	0.12
118	160	6.30	1.0	0.2	0.2	0.10
135	240	10.5	1.0	0.25	0.25	0.10
152	360	13.6	1.0	0.25	0.25	0.10
172	560	27.2	2.0	0.3	0.3	0.10
194	880	47.0	2.0	0.3	0.3	0.10
218	1340	70.0	2.0	0.3	0.3	0.09
245	2000	106	2.0	0.35	0.35	0.09
272	2800	149	2.5	0.35	0.35	0.08
305	3900	214	2.5	0.4	0.4	0.08
340	5500	350	2.5	0.4	0.4	0.08
380	7700	480	2.5	0.5	0.5	0.08
430	10300	730	2.5	0.5	0.5	0.08
472	13500	990	2.5	0.6	0.6	0.08
514	16600	1270	2.5	0.6	0.6	0.07
556	21200	1540	2.5	0.65	0.65	0.07

¹⁾Does not apply to type HDS.

Flexibles of sizes 66 to 272 are of the compound type with a hard core and soft thrust pieces.
Sizes 305 to 556 are of 90 ShoreA NBR material.

For maximum coupling torque: T_Kmax = 2.0 · T_KN

For coupling overload torque: T_KOL = 3.0 · T_KN

For coupling fatigue torque: T_KW = 0.15 · T_KN

Torsional stiffness and damping

The values stated in the above table apply to a capacity utilization of 50 %, an excitation amplitude of 10 % T_KN with the frequency 10 Hz and an ambient temperature of 20 °C. Dynamic torsional stiffness is dependent on the load and increases in proportion to capacity utilization. The following table shows the correction factors for different rated loads.

C_Tdyn = C_{Tdyn 50 %} · FKC

	Capacity utilization T_N / T_KN
	20 %	40 %	50 %	60 %	70 %	80 %	100 %
Correction factor FKC	0.7	0.9	1	1.1	1.2	1.3	1.5

The damping coefficient isΨ = 1,4
Torsional stiffness and damping is further dependent on the ambient temperature and the frequency and amplitude of the torsional vibration excitation. More precise torsional stiffness and damping parameters on request.

Permitted shaft misalignment

ΔK_perm = ΔK₁₅₀₀ · FKV

	Speed in rpm
	500	1000	1500	3000
Correction factor FKV	1.6	1.20	1.0	0.70

The axial misalignment must occur dynamically at frequencies up to 10 Hz. For fitting a maximum gap dimension of S_max = S + ΔS and a minimum gap dimension of S_min = S – ΔS are permitted.

Shaft misalignment ΔK_a, ΔK_r and ΔK_w may occur simultaneously.

Assignment of N-EUPEX sizes to IEC standard motors

The assignment applies to an application factor of 1.25.

Outputs P_M of IEC motors and assigned N-EUPEX couplings

Three-phase motor	Output at ≈ 3000 rpm	N-EUPEX coupling	Output at ≈ 1500 rpm	N-EUPEX coupling	Output at ≈ 1000 rpm	N-EUPEX coupling	Output at ≈ 750 rpm	N-EUPEX coupling	DE shaft end D x E to IEC
Size	P_M	Size	P_M	Size	P_M	Size	P_M	Size	D	E
	kW		kW		kW		kW		mm	mm
56	0.09	58	0.06	58					9	20
	0.12	58	0.09	58
63	0.18	58	0.12	58					11	23
	0.25	58	0.18	58
71	0.37	58	0.25	58					14	30
	0.55	58	0.37	58
80	0.75	58	0.55	58	0.37	58			19	40
	1.1	58	0.75	58	0.55	58
90S	1.5	68	1.1	68	0.75	68			24	50
90L	2.2	68	1.5	68	1.1	68			24	50
100L	3	80	2.2	80	1.5	80	0.75	80	28	60
			3	80			1.1	80
112M	4	80	4	80	2.2	80	1.5	80	28	60
132S	5.5	95	5.5	95	3	95	2.2	95	38	80
	7.5	95
132M			7.5	95	4	95	3	95	38	80
					5.5	95
160M	11	95	11	95	7.5	95	4	95	42	110
	15	95					5.5	95
160L	18.5	95	15	110	11	110	7.5	110	42	110
180M	22	110	18.5	110					48	110
180L			22	125	15	125	11	125	48	110
200L	30	125	30	125	18.5	125	15	125	55	110
	37	125			22	140
225S			37	140			18.5	140	55	110
									60	140
225M	45	125	45	140	30	140	22	140	55	110
									60	140
250M	55	140	55	160	37	160	30	160	60	140
									65	140
280S	75	160	75	180	45	180	37	180	65	140
									75	140
280M	90	160	90	180	55	180	45	180	65	140
									75	140
315S	110	160	110	200	75	200	55	200	65	140
									80	170
315M	132	160	132	200	90	200	75	200	65	140
									80	170