Standard Porcelain Bushings | Up To 33kV 36kV Bushings | BS EN ISO 60137

Webster-Wilkinson Porcelain Bushings

Standard Porcelain Bushings

This range of standard porcelain bushings has been popular around the world for many years. The Webster-Wilkinson standard range of bushings have a proven longevity and many thousands continue to operate to this day.

These bushings are especially useful in non-standard transformers, especially where very high pollution levels exist. The range has enhanced insulation levels in excess of the requirements set by ISO 60137 standards.

Designation – Oil/Air – Outdoors
Compliance Standards – BS EN ISO 60137 –Insulated bushings for alternating voltages above 1000 V
Available Designs – Standard bushings rated at 36kV and above are normally filled with oil and ready for service. For some voltages we are able to offer high current versions
Insulators – A one-piece insulator manufactured from ceramic porcelain. Standard porcelain colour is Brown. Grey porcelain also available – Contact T&D for lead times
Termination – Most bushings are supplied with screwed terminals. High current versions are supplied with plain terminals to enable termination via flag connectors
Metalwork – The conductors are electro-tin plated. All fixings and fasteners are anti-corrosion plated
Fixings – Bushings are supplied with an aluminium flange with drilled fixing holes to accept transformer cover studs. The flange is fixed to the porcelain with galvanised finger clamps.

standard porcelain bushings – specification

Standard Bushing Order Code	kV	A	BIL	AC	Creepage	Prot	mm/kV	Class
S0.6	0.6	850	35	16	57	48	95	IV
S1.1	1.1	850	35	27	108	48	98	IV
S3.6	3.6	850	55	30	133	57	37	IV
S3.6HC	3.6	3300	55	30	133	76	37	IV
S7.2	7.2	850	75	35	171	86	23	II
S7.2HC	7.2	3300	75	35	171	86	23	II
S12	12	630	95	40	241	116	20	II
S12 HC	12	2500	95	40	254	128	21	II
S15	15	850	120	68	470	113	31	IV
S24	24	630	150	70	432	200	18	I
S24 HC	24	3300	125	50	457	205	19	I
S36 HC	36	3300	200	110	620	260	17	I
S52	52	1600	260	120	838	280	16	I

Joints | Terminations | Connectors MV HV 11kV 33kV 66kV

porcelain bushings

Webster-Wilkinson offer a complete range of bushings which utilise porcelain insulation designed for use in power transformers, distribution transformers and pole mounted transformers operating at LV MV HV electrical voltages.

Porcelain insulation is a proven technology which provides low cost, long life and maintenance-free solutions which can withstand all environmental conditions.

For a given operating voltage porcelain insulators can be provided with varying creepage distances depending on environmental conditions.

Porcelain bushings are normally supplied with brown glaze however if required, they can be given a grey glaze. All bushings meet the requirements of BS EN ISO 60137 Standards.