For over 100 years we have been supplying high-voltage insulators for electric power transmission and distribution systems to customers world wide. Millions of ceramic and thousands of silicone rubber insulators have been in service for decades without failure or problems. This performance has won us the confidence of our global clientele. Products of uncompromising quality, backed by comprehensive expertise and the competence gathered through years of experience, have made us a preferred supplier to the industry. Lapp Insulator insulators are among the safest and most dependable components in high-voltage engineering anywhere.
Solutions through dialogue make the difference
Insulators in high-voltage systems are exposed to high and widely changing loads. Their electric insulating and mechanical capability must be ensured even under extremely adverse environmental conditions. An appropriate design of the insulating material to meet the specific requirement profile is an important prerequisite for achieving many years of reliable service.
Harnessing all success factors
When it comes to solving special high-performance insulating tasks, we not only bring to bear our entire application technology expertise and long experience. From the outset of each project, we also make sure to obtain the appropriate input from production, costing and logistics experts. This approach ensures that all success factors will be duly taken into account and that the development of new insulator concepts will proceed quickly and efficiently. Simultaneous engineering saves time and duplicate product trials, thereby cutting costs - a decisive benefit for the customer and ourselves in today`s competitive environment. Even where special designs or models are involved, we will take into account volume production conditions from the very start in order to enable an effective and cost-efficient manufacturing process.
A ISO 9001: 2000 certified company
Our high-voltage engineering components are produced under a DIN ISO 9001: 2000 certified quality management system. The aim of our production quality control is to achieve zero-defect performance at all manufacturing stages. This goal can only be met through a complete understanding, appropriate monitoring, and continuous improvement of all processes. By combining a set of process-specific methods, we have created an all-inclusive system which starts with the inspection of incoming feedstock and extends throughout the production chain.
Additional detailed information on LAPP Insulator, our products and services can be found in the Internet at www.lappinsulator.de

The exterior appearance of a high-voltage insulator depends on a combination of various factors determining its specific shape. Designing an insulator for optimum performance requires an exact knowledge and description of all application needs.
Mechanical requirements
The mechanical forces such as bending moments, compression, tension, torsion, etc. acting on the insulator and its connecting system must be accurately specified.
Electrical characteristics
Data such as the lightning impulse flashover voltage, switching impulse flashover voltage and power-frequency flashover voltage define the necessary dielectric strength and insulator length.
Creepage distance requirements
Creepage distances are defined in accordance with IEC 60815 and with customers requirements.
Applicable standards and testing codes
International standards, codes and test specifications are observed in the manufacture of the product.
Customer specifications and installation requirements
Special requirements (connecting dimensions, diameter, etc.) are considered during design.
Environmental conditions
Environmental conditions at the installation site determine the design and number of insulator sheds. (See adjacent examples)

Insulators for high-voltage overhead transmission and traction lines
A basic distinction is made between longrod insulators exposed to tensile loading and line-post insulators subject to compression and bending moments. Our product lines includes both types, both made of technical ceramics or composite synthetic materials.
LAPP Insulator insulators are puncture-proof and distinguished for their high mechanical resistance. Moreover, each product is optimized for the individual ambient conditions.
Many years of continuous refinement have turned overhead power line insulators into one of the safest components in energy transmission engineering.
Single-part long-rod insulators made of technical ceramics are supplied in lengths of up to 1400 mm, with some special designs availale up to 1900 mm. Greater lengths are achieved by combining several longrods into string configurations.
An alternative particularly for very long insulators is our system, which comprises single-part insulators for overhead power lines in length up to 6 meters. 5-meter long insulators of this type, rated for SML = 450 kN, were supplied to Canada for a 765 kV system already in 1978. In Los Angeles, insulators have been giving dependable service in a 500 kV d.c. system since 1984.
Given their lightweight design, our insulators are also suitable for phase spacing applications, thereby opening up new design options in the construction of compact overhead power transmission lines and traditional designs.
Pin-type line-post insulators may likewise be made of technical ceramics or synthetic composite material. One important field of application for medium-voltage insulators are traction wire systems. The use of our insulators in electric railroad traction systems, even on high-speed German Railway lines, testifies to our customers` confidence in the dependability on these components.

Insulators for high-voltage switchgear and substation equipment
In switchgear systems our products are used as solid-type post insulators and for disconnect switch rotary columns. Units up to a height of 2600 mm are of single-part design, with multi-part units being employed for higher voltage levels.
For outdoor circuit breakers we manufacture hollow insulators with cylindrical or curved bores up to an overall height of 2600 mm. These insulator types are required to exhibit a particularly high mechanical resistance in addition to their electric stength
- an easy task for LAPP Insulator insulators.

Continuously enhanced - the production process of high-performance ceramic insulators
Over the decades we have refined the manufacture of ceramic insulators to perfection. Highly sophisticated monitored processes form the basis of a production system in which small customized product runs are implemented with the same precision and reliability as standard volume parts. Our improvement management system ensures an ongoing refinement of all processes and continuous advancement in cost efficiency.
Selected ingredients of high purity and homogeneous properties are weighed, mixed to formula specifications, and subjected to a grinding process. Vacuum extrusion presses form the plastic filter cake into cylindrical blanks (“body”) which are subjected to a closely controlled drying process to condition them for the following shaping steps.
Vertical lathes are used to machine the blank to its desired contour. After a further precision drying stage the unfinished insulator already possesses a high strength due to the clay bond and is ready for the application of the glazing by an immersion process.
The subsequent firing stage creates the very hard ceramic structure.
The insulating body is now equipped with its metal hardware to complete the production process. It is then tested to international standards or customer specifications. For this purpose we maintain a highvoltage testing laboratory in which voltages up to 3 million volts can be generated.
Kaolin
Clay
Alumina
Felspar
Mixing and grinding
Filter pressing
Extrusion
Pre-drying
Machining
Drying
Glazing
Sintering (Firing)
Mounting of metal parts

The insulator blank has sufficient strength to be glazed by immersion.
Insulators are fired at approx. 1350°C.
A precision-controlled drying process conditions the blank for the subsequent produktion stages.
Blanks are machined to their specified contours in a vertical lathe.
A cylindrical blank is obtained by vacuum extrusion.

Modern composites - the key to success
As an alternative and complement to our range of proven ceramic insulators we have continued the development of composite insulators made of high-grade synthetic materials. These products have been noted for their reliable performance in the field since 1967. Our system insulators consist of two components, i.e., a rod or tube made of glassfiber reinforced plastics
(FRP) and a silicone elastomer housing covering the FRP rod. This design allows a separate improvement of the system`s mechanical properties
(determined by the FRP component) and electrical performance (determined largely by the silicone rubber sheath). As a result, our insulators exhibit outstanding mechanical and electrical characteristics exceeding all overhead line and switchgear engineering requirements.
silicon rubber insulators are particularly suitable for
• high contamination applications
• vandalism hazards
• high creepage on a short length
• compact line applications
Key features of composite insulators
• Outstanding resistance against environmental factors such as UV light, ozone, acid, contamination and moisture
• Interior tensile strength higher than steel, despite approx. 75% less weight
• High resistance against discharges and leakage currents
• Drastically reduced leakage currents due to hydrophobic properties (see illustration)
• High explosion resistance of hollow insulators in case of internal pressure build-up

EUROPE All voltage levels since 1964
SOUTH AFRICA All voltage levels since 1975
U.S.A.
AUSTRALIA
All voltage levels since 1975
All voltage levels since 1976
SOUTH AMERICA All voltage levels since 1978
NEW ZEALAND All voltage levels since 1984
EMIRATES All voltage levels since 1985
SAUDI ARABIA All voltage levels since 1985
NORTH AFRICA All voltage levels since 1985
SPAIN
INDIA
All voltage levels since 1990
All voltage levels since 1993
CHINA All voltage levels since 1991
Complete reference list available on request
With decades of unsurpassed service reliability sillicone rubber insulators have and still provide the best solution world wide in all climatic and pollution conditions .

Patented manufacturing expertise for Isolators
The first manufacturing stage is the continuous pultrusion process yielding the FRP rod. The combination of a hydrolysis resistant epoxy resin with acid resistant glass fibers (ECR glass) is a safe assurance against brittle fracture. Rods are cut to length and visually inspected before being coated with a seamless sheath of high-temperature vulcanized (HTV) silicone rubber ensuring optimum adhesion. Prefabricated sheds are mounted on to the rod to complete the insulator.
A subsequent vulcanizing stage creates a durable high-strength bond between the sheds and the rod sheath. The metal hardware is mounted by a cold-forming process and all insulators are subjected to mechanical inspection, after which the joints between the FRP rod and the metal components are sealed with a special silicone elastomer. This metastable compound creates a perfect seal which prevents the ingress of moisture for an unlimited period of time.
A modular system comprising FRP rods of different diameters and any desired length up to 6 meters, various shed configurations ( shapes, numbers, spacings) and a wide range of assorted end fittings allows the longrod insulator to be optimized for any specific application.
Pultrusion of the FRP rod
Application of HTV silicon sheathing
Shed mounting and vulcanization
Mounting of metal end fitting and sealing

FRP rods are seamlessly coated with HTV silicon.
Safe and durable sealing is achieved by a special process.
The sheds and rod sheath are joined by vulcanization.
A modular system of variable lengths, different shed shapes and sizes and a matching range of metal end fittings allow insulators to be customized for any conceivable application.

LAPP Insulator GmbH & Co. KG
Bahnhofstrasse 5
D-95632 Wunsiedel
Germany
Phone: +49 (0) 9232 / 50-192
Fax: +49 (0) 9232 / 50-106 www.lappinsulator.de