Machine Screw Factory Countersunk head screw, also known as flat machine screw, its head is a 90-degree cone, similar to common wood screws. On the surface of the mounting hole on the connector, a 90-degree conical socket is machined, and head of the countersunk head screw is in the socket and is flush with the surface of the connector. In addition to countersunk head screws, there are also semi-circle head flat machine screws used in some occasions. This kind of screw is more beautiful and can be used in places where a little protrusion is allowed on the surface. Flat countersunk head screws are an indispensable necessity in daily life or industrial manufacturing. According to various properties and functions, it is divided into countersunk head socket head cap screws, countersunk head slotted screws, etc. Production Process of Countersunk Head Screw Specification of Countersunk Head Screw Thread d M3 M4 M5 M6 M8 M10 M12 (M14) M16 (M18) M20 (M22) M24 P0,50,70,811,251,51,75222,52,52,53 a 2掳90掳60掳 0 b l?125mm12141618222630343842465054 125200mm-----4549535761656973 c approx.0,20,30,30,30,40,50,50,50,50,50,511 dk nominal=max.681012162024273033363639 min.5,77,649,6411,5715,5719,4823,4826,4829,4832,3835,3835,3838,38 da max.3,64,75,76,89,211,213,715,717,720,222,424,426,4 ds nominal=max.345681012141618202224 min.2,863,824,825,827,789,7811,7313,7315,7317,7319,6721,6723,67 e min.2,32,873,444,585,726,869,1511,4311,4313,7213,721616 k max.1,72,32,83,34,45,56,577,588,513,114 r min.0,10,20,20,30,50,51111111,6 s nominal22,534568101012121414 min.2,022,523,024,025,026,028,02510,02510,02512,03212,03214,03214,032 max.2,12,63,14,125,146,148,17510,17510,17512,21212,21214,21214,212 t nominal=max.1,21,82,32,53,54,44,64,85,35,55,98,810,3 min.0,951,52,052,253,24,14,34,555,25,68,449,87 Thread d M3 M4 M5 M6 M8 M10 M12 l lengths ls and lg nominal min. max. ls min. lg max. ls min. lg max. ls min. lg max. ls min. lg max. ls min. lg max. ls min. lg max. ls min. lg max. 87,718,29-3,2-4,4-5,2-6,3 109,7110,29-3,2-4,4-5,2-6,3-8,2 1211,6512,35-3,2-4,4-5,2-6,3-8,2-10 1615,6516,35-3,2-4,4-5,2-6,3-8,2-10 2019,5820,42-3,2-4,4-5,2-6,3-8,2-10-11,8 2524,5825,4210,513-4,4-5,2-6,3-8,2-10-11,8 3029,5830,4215,51812,516-5,2-6,3-8,2-10-11,8 3534,535,5 17,5211519-6,3-8,2-10-11,8 4039,540,5 22,52620241722-8,2-10-11,8 5049,550,5 3034273221,72816,524-11,8 6059,460,6 31,73826,53421,2530 7069,470,6 36,54431,2540 Thread d (M14) M16 (M18) M20 (M22) M24 l lengths ls and lg nominal min. max. ls min. lg max. ls min. lg max. ls min. lg max. ls min. lg max. ls min. lg max. ls min. lg max. 2019,5820,42 2524,5825,42-13 3029,5830,42-13-13,5 3534,535,5-13-13,5-15,5-16 4039,540,5-13-13,5-15,5-16-20,6 5049,550,5-13-13,5-15,5-16-20,6-23 6059,460,61626-13,5-15,5-16-20,6-23 7069,470,62636223215,528-16-20,6-23 8079,480,63646324225,53821,534-20,6-23 9089,390,7 425235,54831,54427,540-23 10099,3100,7 45,55841,55437,5503146 7069,470,6 36,544 Application Area of Countersunk Head Screw Flat countersunk head screws can be used in many places, such as electronic products, kitchen supplies, construction, outdoor facilities, office supplies, etc. How to Buy Countersunk Head Screw from Us? Inquiry There are two types of fasteners. One is standard parts, such as DIN7991, flat head countersunk screws. The other is non-standard parts. If you want standard pieces, you can tell the standard, size, grade (material), coating and quantity. For example, you want to buy DIN7991, M10, grade 8.8, galvanized and 20000pcs. If you want non-standard parts, you can show us samples, drawings or detailed instructions. Then our engineers will make technical drawings for you. Price and payemnt The price can be price/piece, or price/kg. We can quote EXW, FOB, CFR ,CIF with T/T, L/C, Western Union,etc. Or other ways agreed with customers. Order After checking, if the price and lead time are both ok, We will start to produce after advance payment according the requirements we promise. Quality Insurance We buy PICC PRODUCTS LIABILITY INSURANCE every year. We can agree in the contract that we will replace the goods or refund the money if there are some quality issues after you get our products. If quality problems happen after use, we will track the goods to deal the problems. And our insurance policy can cover your lost. FAQ Q1: Are you a factory or trading company? A: We are manufacturer of hex bolts and nut for more than 20 years . We have two factories, one in Shanghai and the other in Jiangsu. Our production capacity can be 20000 + tons per year. We can customize our products according to customers' requirements, drawings and samples. Q2: How many years you do foreign trade? A: We have more than 20 years experience in exporting products to worldwide countries with our best quality. Now we have exported more than 40 countries, such as Spain, Germany, Italy, Belgium, United Kingdom, Lithuania, USA, Canada, Australia, Singapore,Japan, Thailand, Malaysia, South Korea,Indonesia, Egypt, Philippines and so on. Q3: Do you have enough outputs? A: We have enough stock in warehouses with abundant capital. We offer 24-hour services. For most common standards, we have them on stock, such as hex bolts, hex nuts, etc. Q4: How to ensure that every process's quality? A: First, we have technical drawings for each product when producing. Second, our workers most have more than 10-years experience of doing hex bolts. Third, our QC people will do inspection every 2 hours. If finding the bad parts, they will stop the porduction immediately. Then,the finished parts will be checked again before shipment which insures every product's quality. Q5: How to ensure the safety of long-distance transportation? A: We pack into cartons first, and then pack cartons on pallets. The pallet is very easy to lift by Forklift wihch will protect the cartons from damage. Professional packing teams which keep every packing safely. Q6: What products can you customize? A:One is standard parts, such as DIN933, hex bolts. The other is Non-standard parts. If you want standard parts, you can tell the standard, size, grade(material) ,coating and quantity. For example, you want to buy DIN933, M12X60,grade 8.8, zinc plated and 20000pcs. If you want non-standard parts, you can show us samples, drawings or detail descriptions. Then our engineer will do the technical drawings for you. There are many, such as hexagon bolts, flange bolts, round head square neck bolts, as well as track bolts, U-bolts, T-bolts, flat head hexagon bolts, hex nuts, hex flange nuts . Q7: Can you provide some sample? A: Samples can be provided as your requirements.Machine Screw Factory website: