Fish paper is a durable fiber material used for insulation and protection in a variety of electrical and industrial applications. It can be supplied in rolls, sheets and other forms, depending on how it will be used.
For generator maintenance, fish paper is commonly used to line rotor skid pans and help protect stator core surfaces during rotor maintenance, removal and installation.
What is fish paper used for?
Fish paper is used in electrical equipment and industrial applications where a durable fiber material is needed. Common uses include:
- Generator rotor skid pan lining
- Electrical insulation in motors and generators
- Insulating barriers and protective layers (such as separating AC and DC circuits and helping protect against shorts to ground)
- Gaskets, washers and other cut components
The thickness, dimensions and form depend on the application.
Why is it called fish paper?
Believe it or not, fish may have inspired the name—or at least the smell.
One story says that early fish paper manufacturing used large amounts of water from rivers and lakes, and that the material had a fishy smell during production. According to this account, the smell gave “fish paper” its memorable name.
The origin of the name has not been confirmed, so we’ll leave this one in the category of industry lore.
Why is fish paper used for generator rotor skid pans?
During generator rotor removal and installation, the rotor moves through a confined space near the stator core. Fish paper can be used to line the skid pan and help protect surfaces during this work.
Roll material can be cut to the length needed for the skid pan. CasTech offers light-gray rolls in several lengths and thicknesses for generator rotor maintenance.
What sizes of fish paper are available?
The size and length of your generator rotor can help determine how much fish paper you need. Where permitted by the job requirements and from a technical or engineering perspective, choosing a shorter roll or a thinner material can help manage material costs. The choice is at the purchaser’s discretion. CasTech’s light-gray rolls are 30 inches wide and available in these sizes:
- 30 mil thick × 30 feet long
- 25 mil thick × 25 feet long
- 25 mil thick × 20 feet long
A dark-green, 15-mil roll is also planned as a two-layer option. Two layers provide 30 mil of fish paper.
Coming soon: innovation in dark-colored fish paper
Our forthcoming dark-colored fish paper introduces a new approach to two-layer applications, designed to save time during generator rotor skid pan preparation. Two 15-mil layers provide 30 mil of fish paper. Because 15 mil is a widely used thickness, longer production runs help optimize manufacturing costs and support competitive pricing, with the goal of reducing the customer’s total cost.
Interested in learning more or reviewing samples when available? Contact CasTech to let us know.
Explore fish paper sizes and selection.
What does “mil” mean?
A mil is one thousandth of an inch. It describes the thickness of the fish paper: 15 mil is 0.015 inch, 25 mil is 0.025 inch, and 30 mil is 0.030 inch. Two 15-mil layers together provide 30 mil of fish paper.
What colors does fish paper come in?
Fish paper is available in different colors for different applications. CasTech currently offers light-gray rolls for generator rotor maintenance and is preparing a dark-green option. View the fish paper products.
Can fish paper be cut to size?
Yes. Fish paper supplied in rolls can be cut to the dimensions needed for a particular application. The 20-foot, 25-foot and 30-foot roll lengths give maintenance teams options for different skid pan coverage requirements.
How do I choose the right fish paper?
Start with the dimensions of the area to be covered and the thickness specified for the job. Consider how much material is needed for the skid pan and whether a shorter or longer roll is more practical. For help with available sizes, pricing or ordering, contact CasTech.
Where can I purchase fish paper?
For generator rotor maintenance, visit the CasTech Generator Rotor / Skid Pan collection to explore available rolls and current pricing.
Looking for fish paper for another application? CasTech also offers smaller sizes and different lengths: