When

To install a replacement piston seal after seal removal

Parts required

  • Piston seal

  • Support ring that was removed during piston seal removal

    The support ring is not a wear part and can be reinstalled. Install a new support ring only when the ring is damaged.

  • Pump head seals for reinstallation if necessary

Tools and additional items required

  • Screwdriver, Torx T30

  • Syringe filled with isopropanol

  • Cleaning swab

  • Lint-free tissue

  • Seal-handling tool

12123
Figure: Seal-handling tool (left: closed tool; right: open tool)

No.

Description

1

Removal pin

2

Insertion pin

3

Knurl for opening and closing the seal-handling tool
(opening and closing is required only when using the removal pin)

Parts affected on the pump head

1234576
Figure: Piston seal (here: for left piston)

No.

Description

1

Pump head

2

Piston seal

3

Support ring

4

Pump head seals (for seal wash plate and seal wash plate screws)

5

Seal wash plate

6

Screws, seal wash plate (4 screws)

7

Piston

Follow these steps

  1. Clean the support ring from the inside and outside, using isopropanol, a cleaning swab, and a lint-free tissue.

  2. Pipette a few drops of isopropanol into the cavity of the pump head, on the edge on which the piston seal will rest.

  3. Figure: Edge on which the piston seal will rest
  4. Slide the support ring and the piston seal onto the insertion pin of the seal-handling tool. The open side of the piston seal faces away from the tool.

233121
Figure: Sliding the support ring and piston seal onto the insertion pin

No.

Description

1

Piston seal (open side facing away from tool)

2

Support ring

3

Insertion pin, seal-handling tool

  1. With the insertion pin, push the seal-handling tool into the pump head as far as it goes in and remove the tool. The piston seal and support ring remain in the pump head.

  2. Figure: Support ring installed, covering the piston seal (here: for left piston)
  3. Check that the pump head seals are correctly installed. If the seals came off or if they do not rest properly in the receiving grooves, reinstall the seals. See Installing the Pump Head Seals.

  1. Place the seal wash plate onto the pump head and insert the screws.

  2. Figure: Screws on seal wash plate (here: left plate)
  3. With the screwdriver, tighten the screws crosswise.

  4. Tighten the screws crosswise once again.

  1. Install the piston. See Installing the Pistons.

  2. Install the pump head. See Installing the Pump Head. However, before you run the script to test the pump for leakage, operate the pump for 30 minutes with a backpressure of 80 MPa (recommended) to allow the new piston seals to run in.