VT-S · Slim Full Extension — Veltork telescopic rails

Construction & principle

Series VT-S achieves 100 % extension through an S-shaped intermediate member whose section shape delivers a high moment of inertia. The result is a very narrow yet very rigid slide with minimal deflection across both short and long strokes. It is built to carry load radially onto the moving rail.

Available one-way (S1) — the moving part extends from one side, stroke slightly exceeding rail length — or two-way (S2), extending to both sides. One-way versions can be ordered with extended stroke to 130 % on request. Built-in rubber-damped stops arrest slow manual travel; external end stops are mandatory for fast or automatic motion.

architecture

Minimal deflection

High structural rigidity keeps deflection small even at full extension.

width

Slim profile

The S-section packs high stiffness into a narrow envelope.

open_in_full

Full + extended stroke

100 % access; S1 special order to 130 % of rail length.

swap_horiz

One- or two-way

S1 one-way or S2 two-way travel to suit the layout.

Profile & cross-section dimensions

Cross-section of the VT-S profile. Letter callouts (A width, B height, …) correspond to the dimension table — every size in the series is listed.

Cross-section — VT-S

Extension principle

Cross-section dimensions — all sizes [mm]

Type	Size	A [mm]	B [mm]	K [mm]	D [mm]	J [mm]	Thread
VT-S1	28	17	84	24.5	35	24.5	M5
VT-S1	35	22.5	104	30.5	43	30.5	M6
VT-S1	43	28	120	34	52	34	M8
VT-S1	63	40	208	64	80	64	M10

Dimension callouts

Aoverall section width

Boverall section height

Jtop edge → upper mounting-hole axis

Dspacing between the two mounting-hole axes

Klower mounting-hole axis → bottom edge

Vmounting thread

Mounting interface

Where the holes sit along the rail, what thread they carry, and the section envelope of each size — the two checks before you commit an interface.

Mounting-hole pattern — rail, plan view

The first mounting hole sits 25 mm from each end of the rail; the remaining holes follow a constant 80 mm pitch. The hole count for every catalogue length is listed in the specification tables below.

Mounting threads: M5 (size 28) · M6 (size 35) · M8 (size 43) · M10 (size 63). Countersunk DIN 7991 or cheese-head DIN 7984.

Envelope per size — will it fit?

Size	Section W × H	Thread
VT-S28	17 × 84 mm	M5
VT-S35	22.5 × 104 mm	M6
VT-S43	28 × 120 mm	M8
VT-S63	40 × 208 mm	M10

Dimensions are nominal values from the VT-S engineering catalogue, in millimetres. For a custom hole pattern, length or finish, send us the interface and we return a drawing. Confirm against the released drawing or 3D model before machining mating parts.

Technical parameters & dimensions

Load capacity is per pair of rails.

VT-S1-28 VT-S1-35 VT-S1-43 VT-S1-63 VT-S2-28 VT-S2-35 VT-S2-43 VT-S2-63

VT-S1-28 · 16 lengths

Size	Length L [mm]	Stroke H [mm]	C₀rad [N] (per pair)	No. of holes (rails)	Weight per rail [kg]
28	290	296	1140	3 / 4	1.9
28	370	380	1538	4 / 5	2.4
28	450	464	1938	4 / 6	2.9
28	530	548	2340	6 / 7	3.4
28	610	630	2752	6 / 8	3.9
28	690	714	3154	7 / 9	4.4
28	770	798	3556	7 / 10	4.9
28	850	864	4222	9 / 11	5.4
28	930	950	4480	9 / 12	6.0
28	1010	1034	4108	10 / 13	6.5
28	1090	1118	3792	10 / 14	7.0
28	1170	1202	3522	12 / 15	7.5
28	1250	1266	3390	12 / 16	8.0
28	1330	1350	3172	13 / 17	8.5
28	1410	1434	2980	13 / 18	9.0
28	1490	1518	2810	15 / 19	9.5

VT-S1-35 · 17 lengths

Size	Length L [mm]	Stroke H [mm]	C₀rad [N] (per pair)	No. of holes (rails)	Weight per rail [kg]
35	450	494	2500	5 / 6	4.5
35	530	558	3370	6 / 7	5.4
35	610	646	3816	6 / 8	6.2
35	690	734	4264	7 / 9	7.0
35	770	798	5158	8 / 10	7.8
35	850	886	5602	9 / 11	8.6
35	930	974	6048	9 / 12	9.4
35	1010	1038	6952	10 / 13	10.2
35	1090	1126	7016	11 / 14	11.0
35	1170	1214	6480	12 / 15	11.8
35	1250	1278	6242	12 / 16	12.6
35	1330	1366	5814	13 / 17	13.4
35	1410	1454	5442	14 / 18	14.2
35	1490	1518	5272	15 / 19	15.0
35	1570	1606	4964	15 / 20	15.9
35	1650	1694	4690	16 / 21	16.7
35	1730	1758	4564	17 / 22	17.5

VT-S1-43 · 19 lengths

Size	Length L [mm]	Stroke H [mm]	C₀rad [N] (per pair)	No. of holes (rails)	Weight per rail [kg]
43	530	556	4122	6 / 7	7.7
43	610	626	5206	6 / 8	8.9
43	690	726	5550	7 / 9	10.1
43	770	796	6638	7 / 10	11.2
43	850	866	7746	9 / 11	12.4
43	930	966	8072	9 / 12	13.6
43	1010	1036	9180	10 / 13	14.7
43	1090	1106	10208	10 / 14	15.9
43	1170	1206	9220	12 / 15	17.1
43	1250	1276	8796	12 / 16	18.3
43	1330	1376	8054	13 / 17	19.4
43	1410	1446	7728	14 / 18	20.6
43	1490	1516	7426	15 / 19	21.8
43	1570	1616	6890	15 / 20	22.9
43	1650	1686	6650	16 / 21	24.1
43	1730	1756	6426	17 / 22	25.3
43	1810	1856	6022	18 / 23	26.4
43	1890	1926	5838	18 / 24	27.6
43	1970	2026	5500	19 / 25	28.8

VT-S1-63 · 18 lengths

Size	Length L [mm]	Stroke H [mm]	C₀rad [N] (per pair)	No. of holes (rails)	Weight per rail [kg]
63	610	666	7004	6 / 8	19.9
63	690	746	8504	8 / 9	22.5
63	770	826	10024	8 / 10	25.1
63	850	906	11560	9 / 11	27.7
63	930	986	13104	9 / 12	30.3
63	1010	1066	14658	11 / 13	32.9
63	1090	1146	16218	11 / 14	35.5
63	1170	1226	17784	12 / 15	38.1
63	1250	1306	19354	12 / 16	40.8
63	1330	1386	20928	14 / 17	43.4
63	1410	1466	22504	14 / 18	46.0
63	1490	1546	24082	15 / 19	48.6
63	1570	1626	25664	15 / 20	51.2
63	1650	1706	24728	17 / 21	53.8
63	1730	1786	23654	17 / 22	56.4
63	1810	1866	22668	18 / 23	59.0
63	1890	1946	21762	18 / 24	61.6
63	1970	2026	20926	20 / 25	64.2

VT-S2-28 · 16 lengths

Size	Length L [mm]	Stroke H [mm]	C₀rad [N] (per pair)	No. of holes (rails)	Weight per rail [kg]
28	290	246	1790	4 / 4	1.9
28	370	326	2210	4 / 5	2.4
28	450	406	2634	6 / 6	2.9
28	530	486	3252	6 / 7	3.4
28	610	566	3674	8 / 8	3.9
28	690	646	4100	8 / 9	4.4
28	770	726	4524	10 / 10	4.9
28	850	806	4950	10 / 11	5.4
28	930	886	5162	12 / 12	6.0
28	1010	966	4714	12 / 13	6.5
28	1090	1046	4336	14 / 14	7.0
28	1170	1126	4016	14 / 15	7.5
28	1250	1206	3740	16 / 16	8.0
28	1330	1286	3498	16 / 17	8.5
28	1410	1366	3288	18 / 18	9.0
28	1490	1446	3100	18 / 19	9.5

VT-S2-35 · 17 lengths

Size	Length L [mm]	Stroke H [mm]	C₀rad [N] (per pair)	No. of holes (rails)	Weight per rail [kg]
35	450	350	6050	4 / 6	4.5
35	530	430	6382	6 / 7	5.4
35	610	510	6762	6 / 8	6.2
35	690	590	7600	8 / 9	7.0
35	770	670	8016	8 / 10	7.8
35	850	750	8446	10 / 11	8.6
35	930	830	9292	10 / 12	9.4
35	1010	910	9736	12 / 13	10.2
35	1090	990	9160	12 / 14	11.0
35	1170	1070	8404	14 / 15	11.8
35	1250	1150	7764	14 / 16	12.6
35	1330	1230	7214	16 / 17	13.4
35	1410	1310	6738	16 / 18	14.2
35	1490	1390	6320	18 / 19	15.0
35	1570	1470	5950	18 / 20	15.9
35	1650	1550	5622	20 / 21	16.7
35	1730	1630	5328	20 / 22	17.5

VT-S2-43 · 19 lengths

Size	Length L [mm]	Stroke H [mm]	C₀rad [N] (per pair)	No. of holes (rails)	Weight per rail [kg]
43	530	476	6036	6 / 7	7.7
43	610	556	6530	8 / 8	8.9
43	690	636	7562	8 / 9	10.1
43	770	716	8594	10 / 10	11.2
43	850	796	9094	10 / 11	12.4
43	930	876	10126	12 / 12	13.6
43	1010	956	11156	12 / 13	14.7
43	1090	1036	11660	14 / 14	15.9
43	1170	1116	10784	14 / 15	17.1
43	1250	1196	10028	16 / 16	18.3
43	1330	1276	9372	16 / 17	19.4
43	1410	1356	8796	18 / 18	20.6
43	1490	1436	8286	18 / 19	21.8
43	1570	1516	7834	20 / 20	22.9
43	1650	1596	7426	20 / 21	24.1
43	1730	1676	7060	22 / 22	25.3
43	1810	1756	6728	22 / 23	26.4
43	1890	1836	6426	24 / 24	27.6
43	1970	1916	6150	24 / 25	28.8

VT-S2-63 · 18 lengths

Size	Length L [mm]	Stroke H [mm]	C₀rad [N] (per pair)	No. of holes (rails)	Weight per rail [kg]
63	610	398	23716	6 / 8	19.9
63	690	478	24484	6 / 9	22.5
63	770	558	25434	8 / 10	25.1
63	850	638	26500	8 / 11	27.7
63	930	718	27646	10 / 12	30.3
63	1010	798	28848	10 / 13	32.9
63	1090	878	30092	12 / 14	35.5
63	1170	958	31368	12 / 15	38.1
63	1250	1038	32668	14 / 16	40.8
63	1330	1118	33988	14 / 17	43.4
63	1410	1198	35322	16 / 18	46.0
63	1490	1278	36670	16 / 19	48.6
63	1570	1358	38018	18 / 20	51.2
63	1650	1438	35538	18 / 21	53.8
63	1730	1518	33360	20 / 22	56.4
63	1810	1598	31436	20 / 23	59.0
63	1890	1678	29720	22 / 24	61.6
63	1970	1758	28182	22 / 25	64.2

Part-number builder

VT-S 1 - 28 . 930 . 950 . N

Load capacity is per pair of rails. For S2, the stroke cannot be changed.

Examples

VT-S1-28.930.950
VT-S2-28.530.430.N

Non-standard stroke steps

Any deviation from the catalogue stroke must be a multiple of the step below (set by the ball-cage pitch); a changed stroke affects the rated capacity.

Size	Stroke step
VT-S28	19 mm
VT-S35	24 mm
VT-S43	30 mm
VT-S63	40 mm

Field	Meaning
VT-S	Series — slim full extension
1 / 2	Travel: 1 = one-way · 2 = two-way
28	Size (28 / 35 / 43 / 63)
930	Rail length L [mm]
950	Stroke H [mm] (S2 stroke is fixed)
N	Additional coating if ≠ standard ISO 2081 zinc

Build your part number & request a price

Open the inquiry builder to pick size & length from the live catalogue, assemble the code automatically and send it for a quote.

tune Not sure? Configurator

Technical data

Extension100 % · S1 / S2

Load basisper pair of rails

Peak C₀rad38 kN

Available sizes28 · 35 · 43 · 63

Max rail length1 970 mm

Operating temperature−20 … +80 °C (rubber-damped stops)

Max working speed≤ 0.8 m/s (derates with length) · max accel 1.2 m/s²

MaterialCF53 · hardened raceways

RacewaysInduction-hardened raceways

BallsCarbon-steel balls (stainless on request)

Surface coatingsZinc per ISO 2081 (standard) · zinc-nickel · nickel · E-coat on request

LubricationMedium lithium grease; re-lube every 100 km or 6 months. FDA, cleanroom, marine & temperature greases on request.

Clearance / preloadG1 increased clearance · standard zero-clearance · K1 increased preload

FasteningCountersunk DIN 7991 or cheese-head DIN 7984. Torque (10.9): 22→3, 28→6, 35→10, 43→25, 63→30 N·m.

function Selection & sizing

Rated loads are static C₀ values, applied at the centre of the moving member in the fully extended position. Check against a static safety factor S₀ and verify deflection before specifying.

Static safety factor S₀

1.5 smooth · 1.5–2 normal · 2–3.5 shock & vibration. Keep P / C₀ ≤ 1 / S₀.

Deflection

f = (q / t) · P [mm]

q = travel coefficient · t = model coefficient · P = central load.

Typical applications

Drawer & rack systemsServer / electronics racksMedical equipmentAccess panels & coversIndustrial furniture

Explore the VT range

VT-LLinear guidearrow_forward VT-PPartial extensionarrow_forward VT-XI-beam full extensionarrow_forward VT-OSquare full extensionarrow_forward VT-HHeavy-duty full ext.arrow_forward

Specify your VT-S — custom length, hole pattern or finish.

Configure the exact model and send it for a quote, or let the configurator find the right series first. Our team returns a part number, deflection estimate and 3D model — prototypes in under 14 days.