Mechanical diaphragm

GD series

Mechanical diaphragm metering pump, up to 135 L/h at up to 10 bar

GD series: mechanical diaphragm metering pumps for accurate, repeatable dosing of chemicals and additives. 7 models from 34 to 135 L/h, with pressure up to 10 bar. Pump-head and diaphragm materials are chosen for your liquid; send us the chemical, concentration and temperature and we will confirm the right head.

Reliable cam structure: low noise, flexible disassembly, easy maintenance
Oil-bath lubrication of drive parts for long life; high-precision worm and worm-gear drive
Flow adjustment both when stopped and when running
Multi-layer composite PTFE and elastic rubber diaphragm; material side without diaphragm
Pump heads in PVC, PVDF or 316SS; self-cleaning check valves
Power 380 V three-phase, 220 V single-phase or three-phase, 50/60 Hz; on/off control, or a variable-frequency controller adjusting the stroke speed

View 7 models

Flow: 34–135 L/h
Pressure: up to 10 bar
Models: 7

Sizes

The 7 models of the GD series range grouped by type. Open the Models tab for every model with its performance data.

Type	Flow range	Pressure	Motor	Models
GD	34–135 L/h	8–10 bar	200 W	7

Models

Filter by duty point, mains frequency or size. Click a model for its performance curve and data.

Model table (PDF)

Model	Series	Flow L/h	Pressure bar	Strokes/min	Motor W	Plunger mm
GD030	GD	34	10	96	200	—	Details
GD050	GD	44	10	116	200	—	Details
GD055	GD	59	10	96	200	—	Details
GD070	GD	71	10	116	200	—	Details
GD085	GD	91	10	80	200	—	Details
GD100	GD	101	8	96	200	—	Details
GD130	GD	135	8	116	200	—	Details

Performance range

Every model of the GD series range by flow and pressure. Click a line or dot to open that model with its full data.

Logarithmic scales. Published catalogue data for clean water; the correct model for your duty is confirmed by our engineers.

Dimensions & weight

Net weight and the main dimensions of each model, in millimetres, from the catalogue. Open a model for the labelled dimension drawing.

Model	Weight (kg)	Mounting B	Mounting C
GD030	—	95	301
GD050	—	95	301
GD055	—	112	327
GD070	—	112	327
GD085	—	112	327
GD100	—	112	327
GD130	—	112	327

Spare parts for GD series

Typical wear and service parts for this type of pump. The exact part, material and part number depend on the model, so send us the model code (or a nameplate photo) and we confirm and quote the right one.

Request spare parts quote

Part	What it does
Diaphragm	The flexing membrane that moves the liquid; replaced at the service interval
Check valves (suction and discharge)	Valve balls, seats and springs that give one-way flow
Pump head	Liquid end in the material suited to the chemical
Gaskets and O-rings	Seal the head, valves and connections
Hydraulic oil and relief / bleed valve	Hydraulic diaphragm types only: transmits the stroke and protects against over-pressure
Stroke adjuster and motor	Sets the flow rate and drives the pump

Generic list for this pump type; it is not a part-number catalogue for the series. Our team confirms the correct part for your model before quoting.

Specification & options

Key parameters

Max flow rate135 L/h
Max pressure10 bar
Steady-state accuracy±1 %
Max suction lift2 m water column
Max inlet pressure2 bar
Max ambient+40 °C

Motor options

Code	Description
1	200 W, 3PH 380 V, 50 Hz, 1440 rpm, IP55/F
2	200 W, 1PH 220 V, 50 Hz, 1440 rpm, IP55/F
3	Consult CNP for other motors
4	200 W, three-phase variable 380 V, 50 Hz, 1440 rpm, IP55/F, IC416

Connections

Code	Description
P	NPT thread 1/2" F
Q	Hard pipe fittings of inner pipe nozzle (DN15)
R	Hose connector (6×12 / 6.35×9.52 / 20×28)
X	Special interface

Fluid end and materials

Code	Fluid end
P	PVC fluid end
S	316 fluid end
T	PVDF fluid end
Z	Special fluid end (consult CNP)

Technical data

Typical applications

Environmental protection
petrochemical
chemical
oil refining
electricity
metallurgy
medicine
food

Data basis

CNP metering pump selection manual, printed pp. 11–14

Performance values are taken from the published CNP catalogue data. Our engineers confirm the final selection for your liquid, temperature, supply and site before quoting.