Sealing Sleeve 20mm

The soft 20 mm cup seal with dimensions 20×28×5/2.8 is a sealing element used in the working section of high-pressure pressure-washer pumps. It maintains tightness in the pump operating area, supporting stable pressure and reducing water leakage.

MPN / reference: 40512
Dimensions / size: 20×28×5/2.8
Weight: 0.001 kg

APPLICATION

Cup seal used in service work related to pump sealing, including:

• replacing the sealing element in the head / piston section,
• pump refurbishment as part of a repair kit or single-seal replacement,
• eliminating leaks that cause water seepage and pressure drops,
• periodic inspections of pumps in pressure washers and high-pressure equipment.

SYMPTOMS - WHEN IT’S WORTH REPLACING

Most common signs of cup seal wear:

• water leaks around the pump or working section,
• drop in working pressure despite functional accessories,
• jet pulsation and pressure fluctuations during operation,
• moisture on pump components after downtime (leaks show up “later”),
• visible damage to the seal profile after disassembly.

HOW TO CHOOSE THE RIGHT PART

Accurate fit is critical - similar seals may differ in profile and working height:

• by dimensions: 20×28×5/2.8 (inner diameter, outer diameter, and height/profile),
• by manufacturer MPN / reference: 40512,
• by comparison with the removed part: check the working profile and dimensions before installation.

Differences of tenths of a millimeter in profile can result in leaks or faster wear.

COMPATIBILITY

Compatibility should be determined based on MPN 40512 and the 20×28×5/2.8 size per pump documentation or the parts table.
Do not select the part only by the general “20 mm” description without verifying full dimensions and profile.

[faq]

Will the 20×28×5/2.8 cup seal fit every “20 mm” pump?|Not always. Fit depends on the full size and profile (here: 5/2.8). The safest approach is selecting by MPN 40512 or by comparing with the removed part.
What’s the difference between a soft and a hard cup seal in pump service?|It refers to the seal type used in a given design. The key is to install exactly the part specified by the pump documentation (dimensions and profile), because it affects tightness and system durability.
Can I use an aftermarket alternative for this cup seal?|Yes, as long as it has identical dimensions and profile and is rated for high-pressure systems. If unsure, the safest reference remains the MPN and pump specification.

[/faq]