Machine vs self-tapping vs self-drilling — which should I use?

Use machine screws with pre-tapped holes or nuts; self-tapping screws form/cut their thread in a pilot hole; self-drilling screws drill and tap in one pass for thin steel and aluminium.

Which screws are best for roofing and cladding?

Use hex-washer head self-drilling screws (DIN 7504K) with bonded EPDM sealing washers. Choose TEK point size (#2/#3/#5) based on sheet and purlin thickness.

When should I pick stainless A2 vs A4?

A2-70 suits general indoor/outdoor use; A4-70/80 adds molybdenum for higher pitting resistance and is preferred in coastal/marine and chemical environments.

What’s the advantage of trilobular thread-forming screws?

They create a strong, vibration-resistant internal thread with lower driving torque and reduced strip risk—ideal for thin steel, aluminium and die-castings; no nut required.

Are chipboard and drywall screws interchangeable?

No. Chipboard screws are optimized for engineered woods (MDF/particle board) with deep threads and often Torx drives; drywall screws are bugle-head for gypsum board and paired to wood or metal studs.

Screws

Industrial Screws — Standards, Materials, Types & Applications

Find the right machine screws, self-tapping, self-drilling (TEK), trilobular thread-forming and application-specific screws (wood, drywall, roofing, concrete/masonry, security, thumb/wing) for metal, timber, plastics and composites. Metric sizes M2–M12 (larger on RFQ), multiple head/drive types (PH/POZ/TX/Hex), and materials from carbon/alloy steel to stainless A2/A4 with zinc, black oxide, Al-Zn flake and PTFE finishes.

Common Standards

Machine: ISO 7045 (pan), ISO 7046 (csk), ISO 14583 (TX pan), plus related head forms
Self-tapping: DIN 7981 (pan), DIN 7982 (csk), DIN 7983 (oval)
Self-drilling (TEK): DIN 7504 (types K hex-washer, N pan, P csk, R oval)
Wood / Coach: DIN 97 (slotted csk wood), DIN 571 (coach/lag)
Thumb / Wing: DIN 465/464 (knurled thumb), DIN 316 (wing)
Trilobular / thread-forming: industry trilobular profiles (TAPTITE® style)

Materials / Grades

Case-hardened carbon/alloy steel as applicable
Stainless: A2-70, A4-70/80
Brass & specials on RFQ

Finishes / Options

Zinc (clear/yellow/black), Black Oxide, Al-Zn flake
TEK points #2/#3/#5; sealing/EPDM washers
Security drives: pin-Torx, pin-Hex, two-hole, tri-wing

Browse Screws by Type

Machine Screws

For tapped holes or nuts in metal/plastics. Pan (ISO 7045), countersunk (ISO 7046), hexalobular pan (ISO 14583). Choose A4 for marine.

Self-Tapping Screws

Form/cut their own thread in thin metals/plastics. DIN 7981/7982/7983. Use pilot holes and match point/thread to substrate.

Self-Drilling (TEK) Screws

Drill + tap in one pass for sheets/sections. DIN 7504 types K/N/P/R; pick TEK #2/#3/#5 by thickness. Roofing versions with EPDM washers.

Trilobular (Thread-Forming) Screws

Low driving torque and strong resistance to loosening in thin steel, aluminium and die-castings. No nut required.

Wood Screws

Timber joinery and hardware mounting. Slotted CSK DIN 97, plus Pozi/Torx variants for modern cabinetry and carpentry.

Coach / Lag Screws

Heavy-duty hex head for timber to timber/steel plates. DIN 571. Ideal for frames, formwork and outdoor structures.

Drywall (Gypsum) Screws

Bugle head PH/POZ for board-to-stud fastening. Options for wood or metal studs; fine thread for steel studs, coarse for wood.

Chipboard / Particle Board Screws

Deep thread, often TX (Torx) drive for strong pull-out in particle/MDF boards. Partial thread improves clamping in carcass assembly.

Roofing / Cladding Screws

Hex-washer head TEK with bonded EPDM washer for metal sheets. Colour-cap options; select TEK point by sheet + purlin thickness.

Concrete / Masonry Screws

High-low thread concrete screws for anchors into concrete, brick and block. Use correct pilot and embedment; hex or csk heads.

Security Screws

Tamper-resistant drives (pin-Torx, pin-Hex, two-hole, tri-wing) for public fixtures, signage and access panels. Stainless options for outdoor use.

Thumb Screws

Tool-free adjustment and clamping. Knurled patterns per DIN 465/464; ideal for panels, guards and jigs.

Wing Screws

Hand-tightened wing head per DIN 316. Great for fixtures and frequent assembly/disassembly.

Applications

Electrical enclosures, HVAC & roofing/cladding, OEM machinery, furniture, appliances, automation, carpentry and civil/MEP. Choose self-drilling for one-pass sheet fastening, self-tapping for pilot-drilled thin metals/plastics, machine for tapped holes/nuts, trilobular for robust thread-forming in metals, and roofing with EPDM for weather-tight seals.

Drive/point advice, substrate selection and torque guidance
Bulk & contract pricing, RFQ support and GST invoicing
Fast pan-India dispatch; export packing on request

Request a Quote / Bulk Pricing or WhatsApp: +91-9611591173

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BuyNutBolts — Trusted E-commerce Online Shopping Site for Industrial Fasteners & C-Parts

BuyNutBolts.com caters to both B2B and B2C industrial buyers across India. We specialise in fasteners and C-parts across ISO/DIN/IS standards with multiple grades and finishes: socket head screws, hex bolts, nuts, washers, anchors, rivets, spacers & standoffs, self-clinching fasteners, and more. We provide reliable procurement and supply solutions for MSMEs and enterprises in fabrication, machinery, electronics, automotive, and construction.

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Socket Head Cap Screws — DIN 912 / ISO 4762, button head (ISO 7380), low head (ISO 12474), countersunk (ISO 10642).

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Stainless Steel Fasteners — A2-70 / A4-70 / A4-80 in popular sizes & finishes.

Washers — flat, spring, fender, cup, and special profiles; DIN 125/127/9021.

Anchors & Rivets — wedge/sleeve/chemical anchors; blind & solid rivets.

Self-Clinching Fasteners — nuts, studs, standoffs for sheet metal.

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