Zirconia Ceramic Plungers, Custom to Drawing | MAC
Custom Zirconia Ceramic Plungers Made to Your Drawing
A zirconia ceramic plunger is the reciprocating piston of a plunger pump, made from toughened zirconium oxide. We supply custom zirconia ceramic plungers to your drawing, with engineering review and QA in Hayward, California.
Zirconia plunger specifications start with grade, construction, and your operating duty
A zirconia plunger specification has three parts. The grade, usually yttria-stabilized Y-TZP or magnesia-stabilized Mg-PSZ, sets strength and toughness. The construction, solid ceramic or a ceramic sleeve on a metal base, sets how load and heat reach the ceramic. The operating duty, meaning pressure, media, temperature, and stroke, decides which grade and construction are adequate.
In the datasheets cited below, Y-TZP shows higher flexural strength than Mg-PSZ, while toughness ranges overlap and shift with test method. Request test data to ASTM C1161 (flexure) and ASTM C1421 (toughness). Full grade data sits on zirconia ceramics.
Zirconia plunger grade properties (published supplier data, not MAC-measured values)
Property | Unit (imperial) | Y-TZP | Mg-PSZ |
Density | g/cm³ (lb/in³) | 6.02–6.05 (0.217–0.219) | 5.70–5.72 (0.206–0.207) |
Flexural strength | MPa (ksi) | 1,200–1,240 (174–180) | 500–620 (73–90) |
Fracture toughness K_IC | MPa·m½ (ksi·in½) | 8–13 (7.3–11.8) | 6.3–11.0 (5.7–10.0) |
Thermal conductivity, 20–25 °C (68–77 °F) | W/m·K (BTU/h·ft·°F) | 2.0–2.2 (1.16–1.27) | 2.2–3 (1.27–1.73) |
CTE, 25–1000 °C (77–1832 °F) | 10⁻⁶/K (10⁻⁶/°F) | 10.3 (5.7) | 10.2 (5.7) |
Sources: Y-TZP, CoorsTek YTZP and Precision Ceramics CeramaZirc 3YZ. Mg-PSZ, CoorsTek Dura-Z and Kyocera FZM, which lists density as ≥ 5.70 g/cm³. CTE: CoorsTek only. Test basis differs: CoorsTek 4-point flexure; Kyocera DIN EN 843-1 and SEVNB, values indicative; Precision Ceramics method not stated.
Solid ceramic or a ceramic sleeve on a metal base?
The choice commonly turns on plunger length and diameter and how the plunger mounts to the pump crosshead. A sleeved plunger is a ceramic shell on a metal base, commonly joined by shrink fit or adhesive bonding; show the joint type and operating temperature range on the drawing. For a ceramic plunger in a metal bore, Cummins' patent US 5,899,383 states the ceramic's thermal expansion should match the bore metal as closely as possible.
Which finish, geometry and chamfer callouts belong on the drawing?
Call out Ra over the packing contact length, roundness, straightness and cylindricity of the outside diameter, and the end chamfer. Values come from your pump and packing specification, and the engineering review checks each callout against grade and finishing route before quoting. Grinding practice is covered in precautions for CNC processing zirconia ceramics.
What to send with a plunger RFQ
Input | Why it affects the quote |
Drawing and revision (STEP, DWG, PDF) | Geometry and callouts |
OD × length | Blank size, grinding time |
Solid or sleeved; base interface | Joint design |
Finish, geometry, edge callouts | Finishing and inspection scope |
Pressure, stroke, speed | Stress and wear |
Media, pH, temperature | Aging and corrosion screen |
Packing material | Contact conditions |
Quantity | Routing and price |
Required inspection documents | Reporting scope |
In practical terms, complete inputs reduce clarification before a quote.
Hot water, abrasive media and impact load decide between Y-TZP, Mg-PSZ and the alternatives
Yttria-stabilized zirconia (Y-TZP) suits strength-critical plungers in service that stays out of hot, wet conditions. Hot water and steam can cause low-temperature degradation in Y-TZP, so request aging data for every candidate grade at your service temperature. Impact load and abrasive media call for comparing fracture toughness and hardness on the same test basis.
Low-temperature degradation is a progressive surface transformation of tetragonal zirconia in the presence of water (Chevalier, Gremillard and Deville, 2007); aging behavior is commonly reported to differ by stabilizer and microstructure.
Plunger grade choice by duty
Grade | Fits when | Limitation to check | Source |
Y-TZP | Design is strength-critical | Low-temperature degradation in hot water or steam | Chevalier et al. 2007; Table 1 |
Mg-PSZ | Design has margin below Y-TZP strength | Lower published flexural strength, 500–620 MPa (73–90 ksi) | CoorsTek; Kyocera |
Tungsten carbide: see ceramic vs tungsten carbide.
From an engineering perspective, the grade decision rests on strength margin and service temperature.
Engineering review, application support and QA for every plunger RFQ sit in Hayward, California
Our engineering team at 30995 Santana St, Hayward, CA 94544 reviews zirconia plunger RFQs for manufacturability, grade selection and drawing callouts before a price is issued. Application support and QA sit with the same team. Price and lead time are stated in each quote; we do not publish a standard lead time.
How is lead time set?
From grade, construction, finishing scope, quantity and required documents.
Can you quote a replacement for an existing plunger?
Yes, from a drawing measured from the existing part, plus Table 2 duty data. No fit or compatibility claim is made for any pump brand.
How are zirconia plungers formed, sintered and ground?
Blanks are commonly formed by pressing or injection molding, sintered at high temperature, then diamond ground. Density and strength tend to vary with sintering route.
Which inspection documents can you request?
List them in the RFQ; what can be supplied is stated in the quote.
For procurement purposes, the RFQ, engineering review and quote run through one team.
Cracked, chipped or scored plungers point to four service conditions
Cracking, chipping and scoring of zirconia plungers are commonly traced to four conditions: thermal shock from dry running, edge loading at the plunger end, abrasive particles in the pumped media, and hydrothermal aging in hot-water service. Each leaves a different mark, so the failed part and its service record usually point to the cause.
Plunger failure triage
Symptom | Likely condition | Record before the RFQ |
Cracking after dry running | Thermal shock | Dry-run time; temperature |
Chipping at the end | Edge loading | Chamfer callout; end photos |
Axial scoring | Abrasive media | Solids content; packing type |
Roughening in hot water | Hydrothermal aging | Temperature; service hours |
NOV's multiplex plunger pump manual warns against running a pump dry. Crack mechanisms are covered in why zirconia ceramics crack.
In practical terms, photographs of the failed end plus the service record make a replacement RFQ specific to the cause.
Related parts: fluid control ceramics and ceramic sealing rings.
No drawing yet? Describe the part and duty to Mark Ma: mark@microns-ceramics.com, +1 646 732 7880.
Mark Ma, Lead Materials Engineer
Comments