Bell Approvals: Anodizing, CAD, Chem Mill, Coatings & NDE Certifications

Bell Approved Processes for Precision Finishing and Testing

Magnetic Inspection Laboratory, Inc. (MIL) is a trusted processor for Bell, delivering specialized finishing and testing for defense and industrial components. As an approved provider, MIL meets Bell’s rigorous standards through processes like anodizing, black oxide, cadmium plating, chem film, chemical milling, electropolishing, non-destructive testing (NDT), and welding, backed by Nadcap and AS9100 certifications. With 82 years of expertise, we ensure precision and compliance across multiple industries. Search the table below by process or specification to verify our capabilities.

PROCESS	PROCESS CODE	SPECIFICATION	DESCRIPTION	APPROVED	REMARKS

ANODIZING	PA	BPS 4001 / MIL-A-8625 TY I, TY IB	CHROMIC ACID	✔
	PD1	BPS 4387 / MIL-A-8625 TY III	HARD ANODIZING	✔
	PD2	BPS 4387	HARD ANODIZING (PTFE, TFE COATING)	✔
	PD3	BPS 4387 / MIL-A-8625 TY III	HARD ANODIZING (PTFE, TFE SEALED)	✔
	PM	BPS 4555* / MIL-A-8625 TY IIB	SULFURIC ACID * See note	✔	* SEE NOTE 1 BELOW, APPLIES TO BPS 4555 ONLY

BLACK OXIDE	PF	BPS 4084	BLACK OXIDE	✔

CAD PLATING	PB	BPS4006 / AMS-QQ-P-416 TY I,II, III	CADMIUM PLATE	✔

CHEM FILM	QB1	BPS 4182 / MIL-DTL-5541 TY I	CL 1A	✔
	QB2	BPS 4182 / MIL-DTL-5541 TY I	CL 3	✔

CHEM MILL	QE2	BPS 4389 / MIL-C-81769 / AMS-C-81769	LOW ALLOY STEEL	✔
	QE3	BPS 4389 / MIL-C-81769 / AMS-C-81769	STAINLESS & HIGH ALLOY	✔
	QE5	BPS 4389 / MIL-C-81769 / AMS-C-81769	TITANIUM	✔
	QE6	BPS 4389 / MIL-C-81769 / AMS-C-81769	FORGINGS	✔

CLEANING	PS	BPS 4138	CHEMICAL	✔
	SN4	BPS 4462	CLEAN & DESCALE.OF TI MAT’L	✔

DFL	QI	BPS 4310 / MIL-L-23398 / MIL-PRF-46010		✔

EPOLISH	QQ	BPS 4501		✔

ETCH	QE7	BPS 4389	PRE PENETRANT ETCH ALUM CASTING	✔

PASS	QJ1	BPS 4007 / AMS 2700 ALL TY 1-4	PROCEDURE I	✔
	QJ2	BPS 4007 / AMS 2700 ALL TY 1-4	PROCEDURE II	✔

PHOSPHATE	QC	BPS 4384	STEEL	✔
		MIL-P-16232 / MIL-DTL-16232	Type M only	✔

NDE	IA	BPS 4075 / ASTM E1444	MAG PARTICLE	✔
	IB3	BPS 4089 / ASTM E1417	FPI (WATER WASHABLE) CSTGS; INCLUDES IB1.	✔
	IB4	BPS 4089	FPI (POST-EMULSIFIED) CSTGS/FORG.; INCLUDES IB2.	✔
	IF1	BPS 4309 / ASTM E1742	RADIOGRAPHIC	✔
	IF2	BPS 4309 / ASTM E1742	RADIOGRAPHIC	✔

WELDING	NJ1	BPS 4470	WELDING (IN PROCESS CASTINGS) AL 356/A356/357 ALLOYS	✔

for BPS 4555 but lists BPS 4001 chromic acid anodize as an alternate, MIL can process the part per BPS 4001 and BPS 4001 only.

THE PROCESSES COVERED BY THE FOLLOWING LISTED SPECIFICATIONS REQUIRE BELL APPROVAL :

4001	4302	4408	4463	4518	4570
4003	4304	4409	4465	4520	4574
4006	4305	4419	4467	4522	4578
4007	4309	4420	4469	4523	4579
4012	4310	4424	4470	4525	4580
4017	4312	4425	4478	4528	4581
4022	4328	4431	4487	4529	4582
4075	4339	4432	4488	4531	4583
4083	4351	4436	4490	4541	4584
4084	4352	4437	4491	4542	4586
4089	4357 Sect IV	4439	4492	4543	4587
4092	4359	4440	4495	4544	4588
4098	4364	4445	4496	4546	4589
4110	4366	4446	4501	4548	4590
4113	4383	4448	4503	4549	4591
4138	4384	4449	4508	4551	4592
4139	4387	4453	4509	4552	4594
4140	4389	4454	4510	4553	4595
4162	4400	4455	4511	4554	4596
4163	4401	4456	4512	4555	4597
4182	4402	4458	4513	4556	4599
4207	4403	4460	4514	4558	4600
4212	4404	4462	4517	4563	4601

MIL’s Bell approvals reflect our long-standing commitment to precision and reliability for primes and machine shops. Our one-stop-shop capabilities and rigorous contract reviews ensure consistent quality and on-time delivery (93%+ OTD).

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BELL

Bell Approved Processes for Precision Finishing and Testing