ZTELEC Transformer Diaphragm Conservator (Air Cell) – Oil Isolation & Moisture Protection Solution

The ZTELEC Diaphragm Conservator, also known as transformer air cell or conservator diaphragm, is installed inside the conservator tank to isolate transformer insulating oil from atmospheric air. This isolation prevents moisture ingress, oxidation, and gas contamination, thereby maintaining oil purity and improving transformer insulation reliability. The diaphragm inflates and deflates automatically to compensate for oil volume changes caused by temperature variations during transformer operation.

Working Principle of Transformer Diaphragm Conservator

The diaphragm is mounted inside the conservator tank through a flange connection. As transformer oil expands or contracts due to temperature changes, the diaphragm adjusts its volume accordingly. This mechanism ensures that insulating oil never directly contacts atmospheric air, reducing oxidation and preventing moisture absorption. By maintaining constant atmospheric pressure on the oil surface, the diaphragm preserves dielectric strength and extends insulation system life.

High-Quality Material Construction

ZTELEC diaphragms are manufactured using nitrile rubber coated nylon fabric combined with elastomer coatings such as Acrylonitrile Butadiene Rubber (NBR), Polychloroprene (CR), and Hypalon (CSM). These materials are engineered to minimize degradation, prevent air leakage, and resist aging under thermal and mechanical stress. The optimized rubber formulation reduces gas permeability and improves long-term operational reliability.

Diaphragm Technical Parameters

Cell material: Nitrile Rubber / Coated Nylon Fabric

Air valve material: NBR / Brass / Customized

Cell color: Black / Green / Blue / Customized

Level gauge fitting: NBR / Brass / Customized

Surface finish: Smooth NBR / Clean-free surface

Shape options: D-type, capsule type, bag type or customized

Sizes and dimensions: Customized according to conservator tank design

Material Properties

Material thickness: 0.7 – 1.0 mm

Hardness scale: Shore A 60–65

Permeability (air): 0.1 liter per 24 hours standard

Material elongation: 15–20%

High temperature resistance: up to 100°C

Low temperature endurance: up to -40°C

Volume change at 100°C for 24 hours: 0%

Breathability test: 24.5 kPa × 3 minutes

Mechanical Properties

Longitudinal tensile strength: greater than 2000 N

Latitudinal tensile strength: greater than 2000 N

Material strength rating: greater than 20 kg

Adhesive bonding strength: greater than 2000 N

Oil Resistance Performance

Internal oil temperature resistance: up to 70°C

Oil permeability: 0 – 8.6 g/m²·d

Low oil absorption rate ensures stable insulation performance and minimal aging.

Advantages of ZTELEC Transformer Diaphragm

Completely isolates insulating oil from air, preventing oxidation and moisture contamination.

Maintains constant pressure on oil surface to avoid bubble formation.

Improves dielectric strength and insulation life of transformer.

Prevents corrosion inside conservator tank.

Simple structure with minimal maintenance requirements.

Flexible shapes and sizes for different conservator designs.

Long service life with excellent temperature resistance.

Reduces maintenance time and operational costs.

Applicable Standards

GB/T 5453-1997 permeability testing for coated fabrics

GB/T 1038.1-2022 gas permeability measurement

HG/T 2580-2008 tensile strength testing

GB/T 528-2009 rubber tensile strength

GB/T 531.1-2008 hardness testing

HG/T 2581.1-2009 tear resistance testing

GB/T 3512-2014 thermal aging test

GB/T 31547-2023 air tightness testing

Customization Options

ZTELEC provides fully customized diaphragm conservators based on transformer conservator tank dimensions. Available configurations include bag type, capsule type, and D-type diaphragm. Custom air valve, level gauge fittings, and material options are also available according to project requirements.

Applications

Oil-immersed power transformers

Distribution transformers

Rectifier transformers

Furnace transformers

Generator step-up transformers

Industrial and utility substation transformers

The ZTELEC transformer diaphragm conservator provides a reliable oil isolation solution for extending transformer service life. With excellent mechanical strength, low permeability, and high temperature resistance, it effectively prevents oil contamination and ensures stable transformer insulation performance. Custom sizes and shapes make it suitable for a wide range of transformer applications.