Which material for a NOx sensor housing?

310S for the exhaust-side housing, because it holds oxidation resistance where 304 would scale; 316 or 316L where the housing sees condensate or a corrosive medium more than sustained heat. The grade follows the service environment, not the geometry.

Published configurations

21 published configurations in this family. Heights run 1.0-54.5 mm, outer diameters 6.00-15.80 mm, grades used: SUS 301, SUS 304, SUS 310, SUS 316.

Code	Height	OD	ID	Wall	Material
L020-1	8.2	7.5，7.9，14.37	6.7，7.1，13.6	0.4	SUS 310
L020-2	12.2	8.35，11.2	7.5	0.5	SUS 310
L021	24.5	8.85，14.72，15.13	8.05，14.33，13.92	0.4	SUS 310
L022-2	54.5	12.2，15.25	11.2，14.25	0.5	SUS 316
L023-1	21.7	14.7，15.4	13.7，14.4	0.5	SUS 310
L023-2	14.6	8.2，14.39	7.2，13.6	0.5	SUS 316
L027-3	6.8	6	2	0.3	SUS 301
L029	19.5	10，13.9	9	0.5	SUS 316
L030	1	9	5.5	1	SUS 301
L031	8.9	11.6	10.6	0.5	SUS 316
L037	45.4	12.2，15.25	11.2，14.25	0.5	SUS 316
L038-1	22.5	13.8	12.8	0.5	SUS 310
L033	24.5	8.85，14.72，15.13	8.05，13.92，14.33	0.4	SUS 310
L039-3	-	-	-	-	-
L040	24.6	14.72，15.13	14.33，13.92	0.4	SUS 310
L041	10.1	12.43	11.43	0.5	SUS 304
L035	8.15	10.9	陶瓷卡簧	0.30	SUS 301
L038-2	24	10.7，12.8	9.9，12	0.4	SUS 310
H007-3PT	45.2	12.2，15.8	11.2，14.9	0.5	SUS 316
L034-3	10	7.9，14.3	7.1，13.5	0.4	SUS 310

Showing the first 20 of 21. The complete list is in the sensor housing catalogue.

What changes with the grade

310S work-hardens hard, so a NOx housing usually needs more forming stages or an intermediate anneal, and tooling is specified for the grade rather than inherited from a 304 job. 316 forms more easily but is stiffer than 304, with noticeably more springback.

What to put on the drawing

Maximum continuous temperature, whether the housing sits in the gas path or is shielded, wall thickness and where it is measured, and the sealing-face tolerance. Those four answers decide the grade and the forming route together.

Grade, wall thickness and tolerance are confirmed against the customer drawing. Batch heat treatment, slow wire cutting, passivation, electropolishing, plating, phosphating and coating are placed with qualified external processors and disclosed on the inspection plan. The quality system is ISO 9001:2015 with controls aligned to IATF 16949 requirements.

Related engineering data

Frequently asked questions

How many NOx sensor configurations does Balford publish?

The published catalogue contains 21 NOx sensor configurations, each recorded with height, outer diameter, inner diameter and material per catalogue code.

What sizes are available for NOx sensor parts?

Recorded heights run 1.0-54.5 mm and outer diameters 6.0-15.8. Custom sizes are manufactured to the customer drawing rather than limited to the catalogue.

Which materials are used?

The published configurations use SUS 301, SUS 304, SUS 310, SUS 316. Material, temper and wall thickness are confirmed against the drawing before tooling.

What wall thickness is typical?

Recorded wall thicknesses in this family: 0.30, 0.40, 0.50, 1.00 mm.

How do I get a quotation?

Send a 2D drawing or 3D model with the material, annual volume and the tolerances that matter. A DFM review covering draw ratio, forming stages and thinning comes back before tooling, and the quotation separates tooling cost from piece price.

Written by the Balford engineering team, Zhuji, Zhejiang, China. Last updated 21 September 2026.