Office Chair Gas Cylinders

Office Chair
Gas Cylinders

In the office chair parts, the office chair gas cylinder is one of the most important components. It is also called office chair pneumatic cylinder or office chair gas lift, or simply office chair cylinder, with which users can adjust the height of the chair for comfort. In other words, it plays a very significant role in realizing the biggest ergonomic benefit for users. 

♠ How it work :  There is a cylinder in the pneumatic lift chair. The piston and pneumatic rod in the cylinder move up and down to control the lifting of the chair. The cylinder is filled with nitrogen.

In the following content, we will demonstrate the respective specifications of the gas cylinders from the perspective of the manufacturer. What’s more, we will show you the chair gas cylinders in terms of the physical composition diagram and manufacturing process.

Our Chair Gas Cylinders

How to read the Specifications of Gas Cylinder

The universal gas cylinders generally have an outer tube with a diameter of ∅50 and an inner tube with a diameter of ∅28. (The general gas cylinder diagram is as follows)

The outer tube is connected to the five-star base of the chair, and the inner tube is connected to the tilt mechanism.

There are also gas cylinders with special outer tube specifications, such as the gas cylinder with ∅38 diameter outer tube.

V = Length of outer tube
L1 = Unextended length of the gas cylinder
L2 = The longest length that the gas cylinder can extend
C = Stroke = L2-L1

Welding Gas Cylinder Size Diagram

The Class of Our Gas Cylinder

As an important part of supporting swivel chair/lift chair. The gas cylinder must be strong enough to support a weight of over 450lbs (200kgs).

Therefore, the thickness of the outer tube and the inner tube is very important. 

According to the different load capacity of the gas cylinders, they are divided into four classes.

Class

Class 1

Class 1+

Class 2

Class 2+

Class 3

Class 3+

Class 4

Piston Tube Thickness

1.0 mm

1.2 mm

1.5 mm

1.5 mm

2.0 mm

2.0 mm

2.5 mm

Cylinder Tube Thickness

1.0 mm

1.0 mm

1.0 mm

1.2 mm

1.2 mm

1.5 mm

1.5 mm

Series of Our Gas Cylinder

01 

According to the different production technology of gas cylinder bottom, it can be divided into: Welding, Curling, and Double cone.

Welding Series

The bottom cover of the Welding Series Gas Cylinder is fully welded, which has a good protective effect on the inside of the gas cylinder. This welding process is suitable for all thicknesses of the gas cylinder outer tubes.

Bottom Cover of Welding series Gas Cylinder
Item

XYM-50

XYM-65

XYM-85

XYM-100

XYM-120

XYM-140

XYM-160

XYM-180

XYM-200

XYM-220

XYM-240

XYM-260

C

50mm

65mm

85mm

100mm

120mm

140mm

160mm

180mm

200mm

220mm

240mm

260mm

L1

200mm

210mm

230mm

245mm

265mm

285mm

310mm

330mm

350mm

370mm

420mm

440mm

L2

250mm

275mm

315mm

345mm

385mm

425mm

470mm

510mm

550mm

590mm

660mm

695mm

V

145mm

160mm

180mm

195mm

215mm

230mm

260mm

270mm

300mm

300mm

330mm

380mm

X

60mm

60mm

60mm

60mm

60mm

60mm

60mm

60mm

60mm

60mm

60mm

60mm

Forces/N

350-450

350-450

350-450

350-450

350-450

350-450

350-450

350-450

350-450

350-450

350-450

350-450

Table of Contents

Curling Series

The bottom cover of the Curling Series Gas Cylinder is processed with the crimping treatment. And that makes the appearance of the gas cylinders look nicer. But this only can apply to the outer tubes with thickness of 1.2mm or less (gas cylinders of Class 3 or lower). The outer tubes of 1.5mm or more (gas cylinders of Class 4 or higher) cannot be crimped.

Bottom Cover of Curling Gas Cylinder
Gas Cylinder - Curling Series
Curling Gas Cylinder -size diagram
Item

XYM-50

XYM-65

XYM-85

XYM-100

XYM-120

XYM-140

XYM-160

XYM-180

XYM-200

XYM-220

XYM-240

XYM-260

C

50mm

65mm

85mm

100mm

120mm

140mm

160mm

180mm

200mm

220mm

240mm

260mm

L1

200mm

210mm

230mm

245mm

265mm

285mm

310mm

330mm

350mm

370mm

420mm

440mm

L2

250mm

275mm

315mm

345mm

385mm

425mm

470mm

510mm

550mm

590mm

660mm

695mm

V

145mm

160mm

180mm

195mm

215mm

230mm

260mm

270mm

300mm

300mm

330mm

380mm

X

60mm

60mm

60mm

60mm

60mm

60mm

60mm

60mm

60mm

60mm

60mm

60mm

Y

10mm

10mm

10mm

10mm

10mm

10mm

10mm

10mm

10mm

10mm

10mm

10mm

Forces/N

350-450

350-450

350-450

350-450

350-450

350-450

350-450

350-450

350-450

350-450

350-450

350-450

Double Cone Series

The size of the outer tube of the Double Cone Series Gas Cylinder is in two levels. The top is wide and the bottom is a little narrower. Such a design allows the lower part of the gas cylinder to be more embedded in the connecting hole of the five-star foot, making the chair as a whole is more stable.

Double Cone Gas Cylinder - bottom cover
Gas-cylinder-Double-Cone-Series
Double Cone Gas Cylinder - size diagram
Item

XYM-50

XYM-65

XYM-85

XYM-100

XYM-120

XYM-140

C

50mm

65mm

85mm

100mm

120mm

140mm

L1

200mm

210mm

230mm

245mm

265mm

285mm

 

L2

250mm

275mm

315mm

345mm

385mm

425mm

V

145mm

160mm

180mm

195mm

215mm

230mm

X

60mm

60mm

60mm

60mm

60mm

60mm

 

Y

10~40mm

10~60mm

10~80mm

10~80mm

10~100mm

10~100mm

 

Forces/N

350-450

350-450

350-450

350-450

350-450

350-450

 

02 

According to the surface treatment process of the gas cylinders, it can be divided into: Electroplating, Black, White, etc.

Black and Chrome Gas Cylinder

03

According to the movement function of the piston, it can be divided into:

  • Lifting + 360 degree rotation
  • Lifting + automatic return rotation
  • Locating rod
  • Customized

If you have any custom requirements (non-standard size, pressure, color, function), welcome to contact us!

Automatic Return Rotation

Auto-return Gas cylinder
Item

XYM-120

XYM-140

L1

265mm

295mm

V

215mm

230mm

 

X

60mm

60mm

Locating Rod

Locating Gas cylinder
Item

XYM-65

XYM-85

XYM-100

XYM-120

XYM-140

XYM-160

L1

210mm

230mm

245mm

265mm

285mm

310mm

V

160mm

180mm

195mm

215mm

230mm

260mm

 

X

60mm

60mm

60mm

60mm

60mm

60mm

QPQ Series – customized 

QPQ-series Gas cylinder
Item

XYM-65

XYM-85

XYM-100

XYM-120

C

65mm

85mm

100mm

120mm

L1

210mm

230mm

245mm

265mm

 

L2

275mm

315mm

345mm

385mm

V

160mm

180mm

195mm

215mm

X

60mm

60mm

60mm

60mm

 

 

∅38 mm Series – customized

∅38mm series Gas cylinder
Item

XYM-65

XYM-85

XYM-100

XYM-120

XYM-140

XYM-160

XYM-260

C

65mm

85mm

100mm

120mm

140mm

160mm

260mm

L1

210mm

230mm

245mm

265mm

285mm

310mm

440mm

L2

275mm

315mm

345mm

385mm

425mm

470mm

690mm

V

160mm

180mm

195mm

215mm

230mm

260mm

380mm

X

60mm

60mm

60mm

60mm

60mm

60mm

60mm

The Structure of Chair Gas Cylinder

Disassemble Office Chair Gas Cylinders

For the better understanding of the office chair gas lift, we present one structural picture with the names for the different components inside of the chair gas cylinder.

Meanwhile we collected one video from Youtube and modified it for better explanation of how it works.

The Internal Structure of our Gas Cylinder

Structure of Gas Cylinder

Chair Gas Cylinder Disassembly

Air valve and air whole
Air Valve and Air Whole
Disassemble Air Valve
Disassemble Air Valve

The video is taken from the following link in Youtube

 

https://www.youtube.com/watch?v=zBB8DQQrvek

 

Thanks for the creator David’s hard work, hope he will bring us more wonderful videos.

 

The air valve is the key part for the lift of the cylinder, please check photos

How is Office Chair Gas Cylinder Produced?

storage-area-after-nitrogen-injection

To further explain the chair gas lift, we here bring more information for the production. 

From this section, you will know each detail about the manufacture of the office chair gas cylinder, which is one of the most important components in Office chair parts.

Tube Processing — Chair Gas Lift Raw Materials

Seamless steel tube is necessary while welding tube is prohibited, because welded area is considered to be inhomogeneous.

If welded tube is applied, it will very likely to lead to the following problems:

  • Gas cylinder leaks outnitrogen
  • The tube will be easily deformed under press or shock
Seamless steel tube for office chair gas cylinder
Seamless Steel Tube for Office Chair Gas Cylinder
Seamless Steel Tube - Cut to the right size

 

Seamless Steel Tube

Being cut to the right length

Finishing-polish-and-Concentricing

Surface – in and out Polishing and Concentric Processing for Piston Working Perfect inside the Tube

Curling and Engraved Thread

Chair Gas Cylinder -Before Curling and Engraved

Curling and Screw

Gas Cylinder-After curling-2
Gas Cylinder-After curling-1

Surface-in and out Polishing

– Make the surface smooth to facilitate the movement between tubes and pistons.

– Reduce or clean the scratch 

Concentric Processing

The tube maybe become bending during the transportation or machining, this step will ensure the whole tube is concentric.

Comparing-before-and-after
Comparing - before and after

Ultrasonic Cleaning

Ultrasonic cleaning
Ultrasonic cleaning

After the machining processing, the tube should be with lots of dirt or Iron filings. And before the assemble, those dirty must be clean, otherwise it will hurt the sealing rubber part, especially the o-ring and lead to the gas leakage.

Assemble Office Chair Gas Cylinder

installation for the cyclider bottom
installation for the cyclider bottom

Gas Piston Assembly 

Assembly of Gas Piston in Cylinder  

Gas Valve and Top Sealing Part installed in Cylinder

Assembly of O-ring in Cylinder
Assembly of O-ring in Cylinder

Assembly of O-ring in Cylinder -After
Assembly of O-ring in Cylinder -After

In-cylinder and Mid-cylinder Assembly & Nitrogen Injection

Assemble Mid-cylinder and Gas Injection
Assemble Mid-cylinder and Gas Injection

Assemble Mid-cylinder and Gas Injection- After
Assemble Mid-cylinder and Gas Injection- After

Our Workshop for Chair Gas Cylinders

Dust-free Workshop
Dust-free Workshop
Nitrogen Injection Equipment
Nitrogen Injection Equipment
Nitrogen Storage Area
Nitrogen Storage Area

Second inspection:

lay for 3 days to check the gas leakage.

Storage Area - After Nitrogen Injection-1
Storage Area-After Nitrogen Injection-1
Storage Area - After Nitrogen Injection-2
Storage Area-After Nitrogen Injection-2

Out-cylinder Assembly

Final Pressure Inspection and Logo Printing

Final Assembly

By Manual ( small quantity order )

Final Assembly - Out-cylinder and Gas Spring by manual
Final Assembly - Out-cylinder and Gas Spring by manual

Ready to Delivery

Ready to load
Loading-gas cylinder

Quality Control of Our Gas Cylinder

Certification for our Gas Cylinder

Gas-cylinder-certification

Test for our Gas Cylinder

The following are our daily tests. In order to ensure the quality of the gas rod, we strictly abide by the sampling ratio and test procedures.

Impact-test-gas-cylinder

Impact Test

Tension-Test-gas-cylinders

Tension Test

Salt-fog-test-gas-cylinders

Salt Fog Test

Fatigue-Test-gas-cylinders

Fatigue Test

Revolve-Test-gas-cylinders

Revolve Test

Thrust-Test-gas-cylinders

Thrust Test

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