PTFE STAINLESS STEEL OIL SEAL

SML Back-to-back Lip PTFE Stainless Steel Oil Seal for Separating Two Media

The SML PTFE stainless steel oil seal uses two sealing lips facing opposite directions. It seals a rotating shaft while separating two media and is suitable for vacuum pumps, compressors, mixers and process equipment.

Model: SML
Materials: Modified PTFE / 304 or 316L stainless steel
Temperature Range: Recommended standard range: -90 to 260°C; confirm special low-temperature or short-term high-temperature service
Pressure Range: Vacuum and positive pressure; recommended standard design ≤1.5 MPa, with custom designs for special pressure requirements
Speed Range: Recommended standard speed ≤25 m/s; higher surface speeds require review based on shaft diameter and operating conditions
Compatible Media: Vacuum, gases, lubricating oil, hydraulic oil, cutting fluid, water vapor, solvents and powders, subject to compatibility confirmation
Counterface Requirements: Minimum hardness varies by compound. See the seal material table. Recommended surface finish: Ra 0.1–0.4 μm.
Installation Dimensions: ID = shaft/sleeve outside diameter; OD = housing bore; W = seal case thickness. Use an installation sleeve to protect the sealing lip during assembly.

SML Standard Size Search

Standard sizes enable quick matching. If no size matches, provide the shaft diameter, housing bore and available width for a custom size and material review.

View All Standard Sizes

ID (mm)	OD (mm)	W (mm)
8	22	7
10	22	7
10	25	7
12	25	7
12.7	25.4	5.7
15	26	7
15	28	7
15	30	7
15.87	28.57	7
16	28	7
16	35	7
17	30	8
18	30	7
18	30	8
20	30	7
20	30	8
20	32	7
20	35	7
20	35	8
20	40	7
20	40	10
21.84	33.37	6.35
21.87	33	7
21.87	35	7
22	32	8
22	35	7
22	40	7
22	40	8
24	35	7
24	38	7
25	35	7
25	35	8
25	38	7
25	40	7
25	40	8
25	42	7
25	42	10
25	45	8
25	45	10
25	47	7
25	52	7
26	45	8
28	40	7
28	47	7
30	40	7
30	40	8
30	42	7
30	42	8
30	45	8
30	47	7
30	47	10
30	50	7
30	50	8
30.8	40	7
32	44	8
32	47	8
34.3	50	15.3
35	47	7
35	47	10
35	47	12
35	48	8
35	48	10
35	50	7
35	50	8
35	52	7
35	52	8
35	52	10
35	55	8
35	55	10
35	55	11
35	60	8
36	50	7
36	50	12
36	50.2	12
38	50	7
38	52	7
38	52	8
38	55	7
38.5	52	8
40	52	7
40	52	8
40	52	10
40	55	8
40	60	8
40	60	10
40	62	8
40	62	10
40	65	10
40	75	12
42	51	8
42	55	8
42	56	8
42	62	8
45	58	12
45	60	6
45	60	7
45	60	8
45	60	12
45	60	15.3
45	62	6
45	62	8
45	62	9
45	62	12
45	65	8
45	65	10
45	70	8
45	70	10
45	72	8
46	60	8
47	62	8
48	62	8
48	62	12
48.4	80	7.5
50	65	8
50	65	10
50	68	8
50	70	8
50	70	10
50	72	8
50	72	12
50	75	8
50	75	12
50.8	63.5	6.5
50.8	69.9	9.3
52	72	10
53	66	12
54	76.5	7.5
55	70	8
55	70	10
55	72	8
55	72	10
55	72	15.3
55	72	6
55	75	8
55	75	10
55	85	8
57	76	10
57	76	12
58	72	8
58	75	8
60	75	8
60	75	9
60	75	12
60	80	7
60	80	8
60	80	10
60	81	8
60	85	8
60	95	12
60.5	76	8
62	85	10
63	80	16
65	80	8
65	85	10
65	85	12
65	88.9	12
65	90	10
65	90	12
65	90	13
65	95	10
66.7	92.08	9.5
67	80	12
69.85	88.9	11
70	85	8
70	87	10
70	90	10
70	100	12
72	100	10
73	95.3	9.4
74	100	12
75	95	10
75	95	12
70	100	10
76.2	95.3	10
79.1	104.8	9.5
80	95	8
80	95	10
80	100	8
80	100	10
80	105	12
80	105	13
83	95	8.5
85	100	8
85	100	10
85	105	10
85	105	12
85	110	10
85	110	12
85	120	12.7
90	110	10
90	110	12
90	115	12
90	120	12
92	117.5	13
92	125	12
92.2	124.5	9.7
95	110	9
95	110	10
95	120	10
95	120	12
95	125	12
99	117	12
100	120	10
100	120	12
100	125	12
100	125	13
100	130	12
100	140	13
102	114	8.5
104	122	12
105	120	9
105	125	12
105	130	10
105	130	12
110	130	12
110	140	12
110	140	13
112	140	12
112.85	133.4	8.7
115	140	12
120	140	12
120	150	12
125	145	12
125	150	12
125	155	14
130	150	12
130	160	12
130	160	14
133.3	158.8	12.7
135	160	14
135	165	12
139.7	158.8	12.7
140	165	12
140	170	15
145	165	12
145	175	12
145	180	15
150	168	12
150	180	13
150	180	15
160	185	15
160	190	12
160	190	15
165.7	184.3	11
170	200	15
170	200	16
175	200	15
180	210	12
180	210	15
185	220	12
190	220	15
190	225	18
200	230	15
210	250	18
220	250	12
220	250	15
240	270	15

Frequently Asked Questions

Q1: What types of seals can you customize?

A: We provide in-depth customization based on drawings, sketches, physical samples or equipment models. This includes non-standard dimensions, special structures and material selection for specific operating conditions, providing a one-stop manufacturing solution.

Q2: What is the production lead time for custom products, and is delivery reliable?

A: The standard lead time is 15–30 days, depending on order complexity and tooling preparation. Our production scheduling system supports on-time delivery for volume orders. Expedited scheduling and progress updates can be arranged for urgent projects.

Q3: How do you ensure consistent quality for custom seals?

A: We apply full-process quality control:

Incoming inspection: raw materials are tested for hardness, tensile strength and other physical properties before acceptance.
Process control: first-article approval and in-process inspection are implemented during production.
Final inspection: dimensional tolerances, appearance and function are sampled before shipment to verify compliance with the technical agreement.

Q4: What is the minimum order quantity (MOQ), and can orders be shipped in batches?

A: MOQ depends on the product structure and tooling cost and is typically 10–50 pieces. Large projects can be delivered in batches according to your production schedule to reduce inventory.

Q5: What should I do if products arrive deformed or damaged?

A: Please inspect the shipment before signing for delivery. If you find serious deformation, damage or a discrepancy with the packing list, refuse the shipment, state the reason and contact us immediately. We will respond promptly and arrange replacement or refund.

Q6: How do you confirm that the dimensions and material of a custom product meet requirements?

A: Before production, we confirm the shaft diameter, housing bore, groove dimensions and operating parameters such as media and temperature. Samples can be provided for testing when necessary, and products are supplied with material certificates and inspection reports.

Submit Operating Conditions for Selection Support

Provide ID, OD, W and key operating parameters so we can confirm a standard or custom solution.

Submit Operating Conditions