Valve Plate 55×11 mm — Remeza LH20-2 / LB30-2 / LB40-2, Part No. R 21125017

Which Remeza Compressors Are Compatible with Plate R 21125017

Before ordering, confirm that your compressor model is on the list. For clarification on other Remeza variants — contact an Acvatron SRL engineer: +373 22 503-580.

The Role of the Valve Plate in Compressor Operation

The valve block of a reciprocating compressor is a system of intake and discharge valves that controls airflow. Plate R 21125017 is a spring-steel shut-off element that:

• During intake opens under vacuum, allowing atmospheric air into the cylinder
• During compression closes under pressure, retaining air in the cylinder
• During discharge opens the outlet valve, directing compressed air into the distribution line

During one hour of compressor operation the plate completes tens of thousands of flexing cycles. This is why it is a consumable part with a finite service life that depends on operating intensity, inlet air quality, and thermal conditions.

Three parameters of plate R 21125017 are critical simultaneously:

• Length 55 mm and width 11 mm — determine the sealing area of the valve port; a deviation causes incomplete closure or jamming
• Thickness 0.35 mm — defines the stiffness and valve opening pressure; a different thickness alters the compressor’s operating parameters
• Steel grade — the genuine Remeza plate is made from valve strip with a high fatigue strength limit; low-cost alternatives in ordinary spring steel fail 3–5 times sooner

Technical Specifications

Signs of Wear: When to Replace Plates R 21125017

Timely diagnosis avoids an emergency shutdown and costly piston assembly repair.

Gradual wear — characteristic symptoms:

• Discharge pressure drop of 15–25% below the rated value — the plate no longer seals the port fully
• Longer pressure build-up time — LH20-2/LB30-2/LB40-2 runs longer than usual before the pressure switch cuts off
• Elevated cylinder head temperature — hot air blowing back through an incompletely closed valve
• Increased oil consumption — a consequence of unstable cylinder pressure

Sudden fracture — critical symptoms:

• Sudden pressure drop or complete loss of output
• Metallic rattling or knocking in the valve block area — a broken plate fragment is striking the seat

⚠️ Critical: a valve plate fragment that enters the cylinder will destroy the piston and liner within minutes. If a metallic rattle is heard — stop the compressor immediately and disassemble the head.

Valve Plate Replacement Schedule per Remeza Recommendations

The manufacturer recommends a planned inspection of the valve block and plate condition every 500–1,000 operating hours (depending on load regime). Replace the plates when cracks, deformation, or reduced spring tension are found, or after 2,000–3,000 operating hours under normal conditions.

Replacement procedure:

1. Stop and isolate — disconnect the compressor from the power supply and bleed pressure to zero
2. Cool down — wait until the cylinder head cools to ambient temperature
3. Remove the valve cover — undo the bolts in a cross pattern, evenly
4. Inspect components — examine the seat, springs, retainers; if seat wear exceeds 0.1 mm — lap or replace the valve plate assembly
5. Install new plates — lay plates R 21125017 flat on the locating pins; no misalignment permitted
6. Reassemble with new gaskets — tighten the cover bolts to the torque specified in Remeza documentation
7. Test run — run unloaded for 20 minutes; check pressure and head temperature

Associated Parts for Full Valve Block Service on LH20-2 / LB30-2 / LB40-2

When replacing the plates, we recommend renewing the entire valve kit at the same time:

• Valve plates 55×11×0.35 mm, part R 21125017 — this item (2 pcs. per kit)
• Valve block gasket — seal between the valve plate assembly and the cylinder head
• Valve springs — after 2,000–3,000 operating hours, springs lose their tension
• Piston rings — if oil consumption or crankcase blow-by is also observed
• Cylinder head seals — always replace during disassembly

Check parts availability with Acvatron managers: +373 22 503-580.

Why Genuine Remeza Plates R 21125017 Matter vs. Alternatives

From practice: a plate thickness deviation of just 0.05 mm changes the valve opening pressure and the part’s service life. Saving money on one plate can result in a piston assembly repair costing tens of times more.

Expert Opinion

“Plate R 21125017 is one of those spare parts that customers remember only after the compressor has stopped. On the LB30-2 and LB40-2 I recommend keeping at least two kits in stock — it’s cheap insurance against an emergency production shutdown. It is especially important not to cut corners on the genuine Remeza part: I have seen cases where after fitting a ‘similar’ stainless steel plate at 0.4 mm instead of 0.35 mm valve steel, the compressor could not reach its rated pressure — the cylinder head simply wasn’t filling fast enough. Three parameters on the plate: length, width, thickness — all three must match the original exactly.”

Vitaly Boluchevsky, Chief Engineer at Acvatron SRL, 15 years in the industry

FAQ

❓ How many plates are needed for a full valve block service on one LB30-2 or LB40-2 head? A typical two-cylinder Remeza LB30-2 / LB40-2 cylinder head uses 4 valve plates (2 per cylinder: intake and discharge). Kit R 21125017 contains 2 pcs. — for a full two-cylinder head service, 2 kits (4 plates) are required. Confirm the exact quantity from your compressor serial number with an Acvatron SRL manager.

❓ Can plates from another Remeza model or a different manufacturer be used? This is strongly not recommended. The 55×11×0.35 mm dimension is specific to the LH20-2/LB30-2/LB40-2. Plates from other models (e.g. 57×11 mm for the 2080/2090 series) are not geometrically compatible. Using plates of a different thickness changes the valve opening pressure and shortens the part’s service life.

❓ How should spare plates R 21125017 be stored? In the original packaging, horizontally, without mechanical loads, in a dry place free from temperature fluctuations. Storage period — no more than 3 years: valve steel loses its spring properties under prolonged humidity variations. Do not stack vertically — a plate 0.35 mm thick deforms under its own weight.

❓ Is there an alternative to R 21125017 for emergencies? An alternative may be considered only if it matches the exact specification of 55×11×0.35 mm in valve steel. Acvatron SRL can assist in emergency situations — call +373 22 503-580 and an engineer will identify the nearest compatible option in stock.

Why Acvatron SRL

Genuine Remeza spare parts with documentation Acvatron SRL supplies genuine Remeza spare parts — only the part numbers listed in the factory catalogue. Full accompanying documentation, VAT invoice, and contract for legal entities.

Engineering selection by compressor model Unsure of the part number or quantity? Provide the compressor model and serial number — an Acvatron SRL engineer will select the complete spare parts kit for valve block maintenance.

In stock in Chișinău Consumable spare parts for Remeza compressors are permanently stocked at acvatron.md. Same-day collection after payment.

Technical support Acvatron SRL offers not only spare parts sales, but also technical maintenance, diagnostics, and repair of Remeza piston compressors in Chișinău and throughout Moldova.

Documents for legal entities All items are supplied with full accompanying documentation. For companies — VAT invoice and contract.