ASME B 18.2.1 - 2010 Hex Flange Screws
QBH Made from Grade 8 steel, these screws can be used in high-stress applications, such as valves, pumps, motors, and automotive suspension systems. They are at least 25% stronger than medium-strength steel screws. The flange distributes pressure where the screw meets the surface, eliminating the need for a separate washer. Material meets SAE J429 specifications for quality. Dimensions meet IFI 111 specifications. Grade 8 steel hex head screws are marked with six radial lines. Head height includes the flange. Length is measured from under the flange.
Black-phosphate steel screws are mildly corrosion resistant in dry environments. Zinc yellow-chromate plated steel screws resist corrosion in wet environments.
Match the thread spacing of mating components. Coarse threads are the industry standard;choose these screws if you don’t know the threads per inch. Fine threads are closely spaced to prevent loosening from vibration

QBH Thread Size d | |
PP | UNC | UNF | ds | max | min | s | Basic | max | min | e | max | min | dc | max | c | min | k | max | b | L≤6 | L>6 | r | max | min | | 20 | 18 | 16 | 14 | 13 | 12 | 11 | 10 | 28 | 24 | 24 | 20 | 20 | 18 | 18 | 16 | 0.25 | 0.3125 | 0.375 | 0.4375 | 0.5 | 0.5625 | 0.625 | 0.75 | 0.245 | 0.3065 | 0.369 | 0.4305 | 0.493 | 0.5545 | 0.617 | 0.741 | 3/8 | 1/2 | 9/16 | 5/8 | 3/4 | 13/16 | 15/16 | 1-1/8 | 0.375 | 0.5 | 0.5625 | 0.625 | 0.75 | 0.8125 | 0.9375 | 1.125 | 0.367 | 0.489 | 0.551 | 0.612 | 0.736 | 0.798 | 0.922 | 1.1 | 0.433 | 0.577 | 0.65 | 0.722 | 0.866 | 0.938 | 1.083 | 1.299 | 0.409 | 0.548 | 0.618 | 0.685 | 0.825 | 0.895 | 1.034 | 1.234 | 0.56 | 0.68 | 0.81 | 0.93 | 1.07 | 1.19 | 1.33 | 1.59 | 0.04 | 0.05 | 0.06 | 0.07 | 0.08 | 0.09 | 0.1 | 0.11 | 0.28 | 0.32 | 0.39 | 0.46 | 0.51 | 0.57 | 0.62 | 0.73 | 0.75 | 0.875 | 1 | 1.125 | 1.25 | 1.375 | 1.5 | 1.75 | 1 | 1.125 | 1.25 | 1.375 | 1.5 | 1.625 | 1.75 | 2 | 0.025 | 0.025 | 0.025 | 0.025 | 0.025 | 0.045 | 0.045 | 0.045 | 0.015 | 0.025 | 0.025 | 0.025 | 0.025 | 0.020 | 0.020 | 0.020 | |
Process flow
Cold forging
Annealing treatment(if need) ➨ wiredrawing ➨ clod forging ➨ thread rolling ➨make heat treatment(if need) ➨ Finish ➨ Packing
Materials and Chemical compstition
1008
CHEMICAL COMPOSI % |
C | Si | Mn | P | S | Cr | Ni | Cu | Al |
0.06 | 0.06 | 0.33 | 0.013 | 0.003 | 0.01 | 0 | 0.01 | 0.028 |
1035
CHEMICAL COMPOSI % |
C | Si | Mn | P | S | Cr | Ni | Cu |
0.34 | 0.13 | 0.73 | 0.012 | 0.002 | 0.02 | 0.01 | 0.02 |
10B21
CHEMICAL COMPOSI % |
C | Si | Mn | P | S | Cr | B |
0.2 | 0.04 | 0.81 | 0.017 | 0.007 | 0.017 | 0.0021 |
1045
CHEMICAL COMPOSI % |
C | Si | Mn | P | S | Cr | Ni | Cu |
0.45 | 0.23 | 0.58 | 0.014 | 0.006 | 0.057 | 0.008 | 0.016 |
40CR
CHEMICAL COMPOSI % |
C | Si | Mn | P | S | Cr | Ni | Cu |
0.4 | 0.21 | 0.54 | 0.015 | 0.008 | 0.95 | 0.02 | 0.02 |
35CRMO
CHEMICAL COMPOSI % |
C | Si | Mn | P | S | Cr | Ni | Cu | Mo |
0.35 | 0.22 | 0.59 | 0.01 | 0.003 | 0.93 | 0.01 | 0.01 | 0.21 |
42CRMO
CHEMICAL COMPOSI % |
C | Si | Mn | P | S | Cr | Ni | Cu | Mo |
0.42 | 0.27 | 0.92 | 0.013 | 0.004 | 1.01 | 0.03 | 0.04 | 0.2 |
Finish
PLAIN ZP YZP BLACK HDG DACROMET GEOMET CHROME NICKEL AND SO ON
PACKING
QBH BULK
20-25KG/CTN,36CTNS/PALLET
20-30KG/BAGS,36BAGS/PALLET
ONE TON/BOXES
50KG/ IRON DRUM,12 IRON DRUMS/PALLET
QBH SMALL PACKING
Packing in small boxes according to customer’s requirements
Packing in plastic bag according to customer’s requirements
QBH PALLET TYPE
SOLID WOOD FUMIGATION PALLET
EURO Pallet
THREE SPLINT PALLET
WOODEN BOX
The advantages of QBH
- QBH brand sales to the main quality assurance.
- Years of export trade management, excellent service, word-of-mouth guarantee.
- By working with TUV,escort for quality.
- Customization of non-standard parts can be made according to customer's requirements and drawings.
- For quality customers,we can provide a certain credit period.
FAQ
1. How do you let me trust you.
Jiaxing City Qunbang Hardware Co.,ltd hs its own right of import and export,QBH trademark in China,United States,European Union have been registered.At the same time,you can also check the registration information of our company in the China industry and Commerce system.
2. How about your price.
We will be based on different markets,for different quality and quantity,tailor-made prices for customers,in order to achieve win-win goal.
3. How do you control your quality.
Incoming quality contral( IQC)→Process Quality control(PQC)→Output quality control(OQC),and the random samples is sent to TUV for testing.If the customer received the goods and found quality problems,QBH company promises to be responsible for returning money or replenishing the goods
4. Could you provide free samples?
For new customer, We can provide free samples for standard fastener, But the clients will pay the express
charges. For old customer, We will send you free samples and pay express charges by ourself.
5. Do you accept small order?
QBH company can accept small orders if we have them in stock.Generally speaking,the stock probability of stainless steel fasteners is higher than that of carbon steel fasteners.
6. How about your delivery time
What we pursure is the high efficiency movement pattern,the stainless steel fastener delivery time about 15days,the carbon steel fastener will it about 30days
7. What is your packing.
Usually 25KG/carbon,36CTNS on the pallets,or 20-30kg/Bags,then on the pallet,QBH company personalized packagingis also available,like 10PCS/plastic bag or 10pcs/box,it can print some information
such as LOGO and pattern of customers.
8. What is your payment term
Normally,our terms of payment are TT and L/C,if we cooperate for a long time,we can reach the point of mutual trust,and fully support our customers to become bigger and stronger in the local market.
Not only in the price concessions,but also in the payment can also be made on credit,Specific credit sales time needs to be negotiated separately