ev02 mechanical seal 1

A factory assembled, pressure tested, multi spring, balanced cartridge seal suitable for pumps, agitators & mixers. This compact, low profile seal fits all ANSI pumps without modification.

Order ANSI Pump Mechanical Seals Today

The best part about having industrial standards for pumps is that we can create high-performance ANSI pump mechanical seals that are a step ahead of the rest. As one of our most advanced products, the EV01 Cartridge Seal is ideal for all ANSI pumps. With an easy installation process that requires no real equipment modifications, the Enviro 1 is the mechanical seal for your pumps.

We perform extensive R&D to ensure that our ANSI pump mechanical seals are pressure tested at different levels. With features that enable alignment, compatibility with impeller adjustment pumps, API compatibility, and durability , the EV01 Cartridge Seal is your best option in the market. With our seals, you can always rest easy knowing that you are buying a part that will work as it should.

Order our ANSI pump mechanical seals today and enable your industrial equipment to perform better.

Features and Benefits

  • EASY TO INSTALL – No measuring is required to install the Enviro I cartridge seal.
  • NO SHAFT OR SLEEVE WEAR – There are no dynamic “O” rings on the shaft to cause fretting to your equipment and the seal is designed so that all wear parts are disposable.
  • ALIGNMENT – Stationary seats are resiliently mounted on an “O” ring and allowed to float for maximum face squareness.
  • IMPELLER ADJUSTMENT PUMPS – The Enviro I can be installed on pumps requiring an impeller adjustment after the seal is installed. Adjustments can be made without removing the seal or dismantling the pump.
  • NO MODIFICATION TO EQUIPMENT – The Enviro I low profile seal fits all ANSI pumps without modification and is superior in dimensional specifications to any other single cartridge seal commercially available.
  • API – Given pump information the Enviro I can be manufactured to meet the American Petroleum Institute specifications for many petrochemical services.
  • 3 WAY CLIPS – A clip design that not only centers seal but stops axial movement in both directions.
  • “OFF THE SHELF” AVAILABILITY – The Enviro I seal is available in 1.00″ to 4.00″. Larger shaft diameters are available on request.
  • PRESSURE TESTED – All Enviro I seals are pressure tested before leaving our factory.

Technical Data and Dimensions

ev01crosssection 1

All standard dimensions will be customized to fit your application.

1 1/81.7501.9371.6872.7964.0.8751.437.562
1 1/42.0002.1871.9373.0624.0.8751.437.562
1 3/82.0002.1871.9373.0624.0.8751.437.562
1 1/22.0002.1872.1873.3435.01.0001.437.562
1 5/82.3752.5622.3123.4725.01.0001.437.562
1 3/42.5002.6872.4373.6255.51.0001.437.562
1 7/82.6252.8122.5623.7805.51.0001.437.562
2 1/82.8753.1252.8124.3126.01.0001.437.687
2 1/43.0003.2502.9374.4376.01.0001.437.687
2 3/83.1253.3753.0614.4376.01.0001.437.687
2 1/23.2503.5003.1874.6256.01.0001.437.687
2 5/83.4683.6253.4064.6716.5.8751.562.687
2 3/43.7504.0003.6875.0626.5.8751.562.687
2 7/83.7504.0003.6875.0626.5.8751.562.687
3 1/84.0004.2503.9375.5628.0.8751.562.687
3 1/44.2504.5004.1875.9378.0.8751.562.687
3 3/84.2504.5004.1875.9378.0.8751.562.687
3 1/24.5004.7504.4376.1878.0.8751.562.687
3 5/84.5004.7504.4376.1878.0.8751.562.687
3 3/44.5004.7504.6876.4378.0.8751.562.687

SIZES: Metric and sixteenth seals available against specific orders. Larger shaft diameters available against speficic orders.

1316 SS*9Chemical Grade Carbon*
2Viton**1099.5 Alumina Ceramic*
4316 SS*12316 SS
5Springs: Hast. C13316 SS*
6Drive Pins, 316 SS14316 SS
7316 SS*15S. Steel

*Consult factory

Special material and design features available upon request.

Aflas is a registered trademark of Asahi Flass Co. Ltd.
Hastelloy is a registered trademark of Cabot Corp.
Viton and Kalrez are registered trademarks of Dupont.

Recommended Seal Environmental Controls

ev01 feature 1
recommended seal 1

Easy to install, no measuring

  1. Clean stuffing box face, clean and deburr pump shaft or sleeve.
  2. Lubricate seal sleeve ‘O’ ring with neutral or silicone grease.
  3. Position seal on the shaft to within 1/4″ of the bearing housing.
  4. Reassemble remaining pump parts.
  5. Slide the mechanical seal into position. Tighten all gland bolts, ensuring the gland ‘O’ ring mates with the stuffing box face.
  6. Tighten all set screws to the shaft or the sleeve.
  7. Remove all centering & loading clips.
  8. Connect and pressurize flush.

Total Warranty

All Robco seals are manufactured to exact standards, and are guaranteed free of defects in materials and workmanship. All seals are guaranteed for 90 days from delivery, excepting negligence, misuse and abuse, and will deliver at our expense a new seal to replace any seal found to be defective within said period. No registration card is required.

The warranty is expressly in lieu al all warranties, expressed or implied, and of all obligation or liabilities on our part, including any liability for incidental or consequential damages.


The temperature limits, pH ranges, pressure ratings, feet per box and shaft speeds shown throughout this pamphlet are representative; the service life and performance of these products can be affected by elevated temperatures and other operating conditions such as chemical resistance, shaft speeds, pressure and equipment in which that the product is being installed. The ratings supplied are suggested as a guideline and should only be used for evaluating your specific application. When in doubt, contact Robco or your ENVIROPAK distributor. The information contained in the pamphlet should not be considered to be a warranty, expressed or implied, including, but not limited to, a warranty of merchantability or fitness for a particular purpose. In no event shall Robco be liable for any incidental or consequential damages resulting from the use, misuse or inability to use the products. This exclusion applies regardless of whether such damages are sought based on breach of warranty, breach of contract, negligence, strict liability in tort, or any other legal theory.

All Robco mechanical seals are manufactured, assembled and tested in America.