4145h api 7-1 drill collars are made of modified aisi 4145h chromium molybdenum alloy steel. These drill collar bars are full-length heat treated and water quenched to obtain astm a-370 mechanical properties. Full mechanical and chemical mill test certifications are supplied with all drill collars. These mill test certifications guarantee a hardness range of 285 to 341 bhn and an impact value of 40 ft.-lbs. At room temperature one inch below the surface.
To ensure close tolerance bores, all drill collar bars are trepanned then drifted to api specifications. Bar surface finish is “as rolled” which is original mill finish.
Connections:
All connections are precision-machined to api specifications. Api relief groove pin and bore back box stress relief are available on request. Thread roots are cold-worked to offer a greater resistance to fatigue. All connections are phosphated to minimize galling during makeup and applied with thread storage compound. Thread protectors are installed to ensure adequate joint protection during shipment.
Drill Bits
Drill Machine
Place of Origin.....................Germany Model Number........................TU1245 Weight ....................................3.5 Grade......................................HMS Material..................................Carbon Steel,1308 PDC cutters Shape.....................................ASH
HSS M35 5% Cobalt Centre Drill Bits
HSS M35 5% Cobalt Step Drill Bits Set, Amber FINISHED, 3PCS:4-12, 4-20-4-32MM
170PCS HSS TWIST DRILL BITS SET, 118 DEGREE, DIN338, BLACK FINISHED IN METAL BOX. 1.0-8.0MMX0.5, EACH 10PCS 8.5-10.0MMX0.5, EACH 5PCS.
HSS M35 Cobalt 5% Twist Drill Bits SET, 1.0-10.0X0.5MM, 135 SPLIT POINT, DIN338 STANDARD, Amber Finishing,rose Plastic Box Packing
Best quality api 7-1 standard and sprial drill collar Product description Drill collar is the basic component in the bha which provide weight on the bit for dirlling and keeps the drill string in tension.Drill collar is manufactured from aisi 4145h modified quenched and tempered steel and is heat treatment along its entire length for uniform toughness and durability. Srict netallurgical test are performed pre specifications to ensure that the heat treatment produces consisitent and maxium hardness through the depth of the bar. Feartures and benefits: 1. Hardness rannge of 285 to 341 bhn and a charpy impact value of 40ft/lbs are guaranteed for evenly distributed 16 points in any cross sections at room temperature 2.Connections ar phosphate coated afther machinning to protect the threads from corrosive elements and to prevent galling upon initial make -up Thread roots are cold rolled on api and h0-90 connections 3.Pressed steel thread protectors are supplied fo all drill collar that are equipped with standard connection
Power Screw Bits
