Here are some of the leading national suppliers of lined filters in the United Kingdom:

```markdown

Leading National Suppliers of Lined Filters in the UK

1. Donaldson

   • Specializes in filtration solutions, including lined filters for various industries.

2. Parker Hannifin

   • Offers a range of industrial filters, including those with lined options, across multiple sectors.

3. Hydac International

   • Provides hydraulic and filtration solutions, including customized lined filters.

4. Mann+Hummel

   • Known for their filtration products, including specialty lined filters for different applications.

5. Filtration Group

   • Supplies a variety of filtration products, including lined options suitable for specific industry needs.

6. Bühler Group

   • Offers filtration systems and products, including lined filters used in the food and beverage sector.

7. Eaton Corporation

   • Provides a wide range of filters and fluid management solutions, including lined filters.

8. Sentry Equipment Corp.

   • Focuses on providing filtration systems, including lined filter solutions for process industries.

9. SWECO

   • Supplies filtering and separation solutions, including lined filtration options.

10. GEA Group

    • Offers a variety of processing and filtration equipment, including options with liners for enhanced durability. ```

These companies are recognized in the industry for their product innovations and robust solutions in filtration, including lined filters tailored for various applications.