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In November 2024, I received an inquiry from a customer from Kazakhstan about galvanized threaded fittings. The inquiry include ELBOW, NIPPLE, COUPLING, TEE, UNION, etc., and the material is ASTM A105 galvanized. They are also the main products of our company.

In January 2025, the customer informed us that the project is undergoing final evaluation. The customer confirmed the order details and the quality requirements of the product. We can meet the customer’s needs.

On January 22, we received the customer’s purchase contract.

Purchase Order

ITEM	DESCRIPTION	Connection Type	Size (DN)
ELBOW 90 DEG	ASTM A105 CS-HDG, CL 3000#	FNPT	3/4″ (20)
			1/2″ (15)
			1/4″ (8)
ELBOW 45 DEG	ASTM A105 CS-HDG, CL 3000#	FNPT	3″ (80)
			2″ (50)
EQUAL TEE	ASTM A105, CS-HDG, CL 3000#	FNPT	3″ (80)
			2″ (50)
			1″ (25)
Reducing TEE	ASTM A105, CS-HDG, CL 3000#	FNPT	3″ x 2″
			3″ x 1″
			2″ x 1/2″
NIPPLE	ANSI B 16.11, 3000#, , A105 (HDG)  – 75 mm LG	MNPT	3″ (80)
			2″ (50)
			1-1/2″
NIPPLE	ANSI B 16.11, 3000#, , A105 (HDG)  – 200 mm LG	MNPT	1-1/2″
REDCUING COUPLING	REDCUING COUPLING, NPT, ASTM A105, CS-HDG, CL 3000#	FNPT	1″ x 3/4″
REDCUING COUPLING			3/4″x1/2″
UNION	UNION, ASTM A105, CS-HDG, NPT, CL 3000#	FNPT	3″
			2″
			1-1/2″
ELBOW 90 DEG	ASTM A105 CS-HDG, CL 3000#	FNPT	2″ (50)
			1″ (25)
			3/4″ (20)
EQUAL TEE	ASTM A105, CS-HDG, CL 3000#	FNPT	2″ (50)
			1″ (25)

On February 20, this order was delivered as scheduled, and the product photos are as follows.

Hot Dip Galvanized (HDG) Threaded Fittings

Hot Dip Galvanized (HDG) Threaded Fittings are steel or iron pipe fittings that have been coated with a layer of zinc through the hot-dip galvanization process. This coating provides excellent corrosion resistance, making them ideal for use in harsh environments, including plumbing, water distribution, industrial applications, and outdoor settings.

ASTM A105 Threaded Fittings

ASTM A105 threaded pipe fittings are made of carbon steel and are connected by processing threads. Its main features are easy and quick connection, no welding equipment required, and are suitable for pipeline systems that are not easy to weld or require high connection flexibility.

ASTM A105 Threaded Fittings Chemical Composition

CHEMICAL	LIMITS	C	Mn	P	S	Si	Cu	Ni	Cr	Mo	V
ASTM A105	MIN		0.60			0.10
	MAX	0.35	1.05	0.035	0.040	0.35	0.40	0.40	0.30	0.12	0.08

ASTM A105 Threaded Fittings Mechanical Property

MATERIAL	T.S (MPA)	Y.S (MPA)	EL %	R/A %	HARDNESS
ASTM A105	485 min	250 min	22 min	30 min	197 max

Threaded Fittings Dimension

Threaded 45 Elbow			Threaded 45 ° Elbow				Threaded Tee					Threaded Cross
GB/T 14383  ASME  B16.11
Nominal  Size		Center-to-End						Outside Diameter of Band			Wall Thickness			Length of Thread
DN	NPS	A						H			G min			L5 min	L2 min
		90°   Elbows, Tees, Crosses			45 °  Elbows
		2000	3000	6000	2000	3000	6000	2000	3000	6000	2000	3000	6000
6	1/8 1/4 3/8	21	21	25	17	17	19	22	22	25	3.18	3.18	6.35	6.4	6.7
8	1/4	21	25	28	17	19	22	22	25	33	3.18	3.30	6.60	8.1	10.2
10	3/8	25	28	33	19	22	25	25	33	38	3.18	3.51	6.98	9.1	10.4
15	1/2	28	33	38	22	25	28	33	38	46	3.18	4.09	8.15	10.9	13.6
20	3/4	33	38	44	25	28	33	38	46	56	3.18	4.32	8.53	12.7	13.9
25	1	38	44	51	28	33	35	46	56	62	3.68	4.98	9.93	14.7	17.3
32	1 1/4	44	51	60	33	35	43	56	62	75	3.89	5.28	10.59	17.0	18.0
40	1 1/2	51	60	64	35	43	44	62	75	84	4.01	5.56	11.07	17.8	18.4
50	2	60	64	53	43	44	52	75	84	102	4.27	7.14	12.09	19.0	19.2
65	2 1/2	76	83	95	52	52	64	92	102	121	5.61	7.65	15.29	23.6	28.9
80	3	86	95	106	64	64	79	109	121	146	5.99	8.84	16.64	25.9	30.5
100	4	106	114	114	79	79	79	146	152	152	6.55	11.18	18.67	27.7	33

Key Features of HDG Threaded Fittings (FNPT)

Corrosion Resistance – The zinc coating protects against rust and oxidation, increasing the fitting’s lifespan.

Durability – Suitable for high-pressure and high-moisture environments.

Thread Standards – Typically follow NPT (National Pipe Thread) standards, with:

FNPT (Female National Pipe Thread) – Internal threads

Common Materials – Usually made from malleable iron or cast steel for strength.

Applications – Used in water systems, gas lines, industrial piping, and outdoor installations.

Hot Dip Galvanized vs. Other Galvanizing Methods

Type	Process	Coating Thickness	Durability
Hot Dip Galvanized (HDG)	Fully submerged in molten zinc	50-150 μm	Best (50+ years)
Electro-Galvanized	Zinc applied via electroplating	2-25 μm	Weaker (1-10 years)
Pre-Galvanized (GI Steel)	Zinc coated before fabrication	10-50 μm	Moderate (10-30 years)
Cold Galvanizing (Zinc Paint)	Zinc-rich paint applied	<10 μm	Lowest (Short-term protection)

14 3 月, 2025