Cheonsei KD Pump Model Code: How to Read 33H, 13H and the Rest
KDV-33H-PTC-FWS is the example printed in the Cheonsei KD series manual. Most people reading a Cheonsei KD pump code get stuck on the "33H" in the middle and assume 33 is a pressure or stroke figure. It's actually a flow code, read as A×10 to the power of B, in mL/min.
That flow code is the hard part. Once you have it, the whole model list becomes easy to search. Let's go from left to right.
Reading a Cheonsei KD Pump Code: Five Sections
A full Cheonsei KD pump model splits into five sections: series and construction, option, flow and pressure, wetted materials, and connection/viscosity/power. The Chinese manual's example leaves out the option section, while the English manual keeps a blank slot for it after KDV.
Section one: KD plus V or H
K and D together give the KD series, with D meaning diaphragm type. The third letter is construction: V is vertical, H is horizontal. So one size can be written as either KDV or KDH, and the data table often lists it as KDV,H-33H.
Section two: option
No mark means no option. A is the BLDC motor control unit, E is an air relief valve, and F is a relief valve. If an old nameplate carries an extra letter, this is usually where it sits. A pump with A uses a brushless DC control unit, which is a different control approach from a standard pump adjusted by hand, so never drop that letter when ordering, or the wiring and adjustment won't match on arrival.
The Cheonsei KD Pump Flow Code: A×10 to the Power of B
On every Cheonsei KD pump, the flow code is two digits. The first is A, the second is B, and nominal flow equals A times 10 to the power of B, in mL/min.
- 33H: 3×10³, nominal 3000 mL/min;
- 13H: 1×10³, nominal 1000 mL/min;
- 52H: 5×10², nominal 500 mL/min;
- 21H: 2×10¹, nominal 20 mL/min;
- 54L: 5×10⁴, nominal 50000 mL/min.
Nominal flow is not real capacity
This is where most mistakes happen. The code is only a size step. Real capacity is in the data table, split into 50Hz and 60Hz columns. The 13H is nominally 1000 mL/min, but the table gives 850 at 50Hz and 1020 at 60Hz. The 33H is nominally 3000, with 2900 at 50Hz and 3480 at 60Hz. The 54L is nominally 50000, with 45000 at 50Hz.
On a 50Hz supply, size from the 50Hz column. Size a Cheonsei KD pump on the nominal figure and it often falls short on site. Table capacities are measured at maximum discharge pressure, and the effective adjustment range is 20%–100% of stroke.
Watch the units as well. Cheonsei lists mL/min, while many engineers work in L/h. Multiply by 60 and divide by 1000: 2900 mL/min is 174 L/h. Enquiries that mix up mL/min and L/h are common, and the error is more than tenfold. When a figure looks odd, ask about units first.
The Pressure Letter Is Relative
On a Cheonsei KD pump, the letter after the flow code is the pressure rank: H high, M middle, L low, S special. That letter only ranks pressure within the same flow step. It is not a fixed value.
In the same 3×10³ step, the 33H is rated 10 bar maximum discharge pressure and the 33L only 5 bar. The 73H is 7 bar against 3 bar for the 73L. The 23H says H but is rated 8 bar, and the 34H is also H at just 5 bar. So to know the pressure of a Cheonsei KD pump, ignore the letter and read that row of the table.
The table also includes a 14N. N isn't in the manual's pressure rank list, so for codes like that, go by the table values.
Materials, Connection, Viscosity, Power
The three material letters
In PTC, the letters are head, diaphragm and check ball. For the head, P is GFPP or PVC, F is PVDF, and S and 6 are two grades of stainless steel. For the diaphragm, T is PTFE and E is EPDM. For the ball, C is ceramic and S and 6 are stainless steel. The usual standard sets are PTC, FTC and STS.
Material also sets the liquid temperature a Cheonsei KD pump can take. The manual gives 0–50℃ for PVC and PVDF heads and 0–80℃ for stainless heads, with ambient at 0–40℃.
The last three: FWS
F is flange, H is hose, X is special. W is standard viscosity, V is high viscosity. The final S is standard power supply, X is special. Take care with the power code: the Chinese manual lists standard as 50Hz 220/380V, while the English manual lists three-phase 60Hz. Go by the nameplate confirmed by your supplier.
Searching the Cheonsei KD Pump Model List Quickly
Don't read the list from the top. First find the rows whose 50Hz capacity covers your maximum dose, then check pressure against the injection point, and only then settle materials and connection. Models in the same flow step with different pressure ranks can differ a lot in weight, so check base and installation dimensions for the exact model. Don't reuse a low-pressure foundation drawing for a high-pressure Cheonsei KD pump.
Replacements need care too. Plenty of customers order from the flow code alone, then find the old head was stainless and they ordered plastic, or the old pump had flanges and they ordered hose. Copy every position on the nameplate. If one is unreadable, send a photo rather than guessing.
One more site lesson: the table notes self-priming capacity of 1 m. If the tank level sits well below the pump, even the right model won't draw chemical. Keep the liquid level above the pump head where you can.
Conclusion
Three things decode a Cheonsei KD pump: V/H for vertical or horizontal, the two digits as A×10 to the power of B for nominal flow, and the letter after them as a relative pressure rank. For actual selection, take both flow and pressure from the 50Hz column of the table, and use the nominal value only to find the right size step quickly.
FAQ
Does a KDV Cheonsei KD pump have the same flow as a KDH?
For the same flow code, the table lists them together with the same flow and pressure. The difference is vertical versus horizontal construction, so mounting and weight differ.
What flow is a 22H?
Nominally 2×10², or 200 mL/min. The table gives 210 mL/min at 50Hz and 260 mL/min at 60Hz, at 10 bar.
Is the H in the flow code the same as the H in the connection code?
No. The H after the flow code is the high pressure rank. The H in the last three positions means hose connection. Different position, different meaning.
Is a Cheonsei KD pump still accurate at very short stroke?
The manual gives an effective adjustment range of 20%–100% of stroke. Below 20% you are outside that range and accuracy isn't assured. For very small flows, pick a smaller flow code.
Can a PVC head handle chemical at 70℃?
No. PVC and PVDF heads are limited to 50℃. At 70℃ you need a stainless head, and the chemical must not attack stainless steel.
Send us the old nameplate or your duty through our contact page. We'll check the Cheonsei model with you and can suggest a NEWDOSE option for the same conditions.