What is the recommended torque for a Flange connection kit, carbon steel, DIN 931 with class 5.6 bolts and class 8 nuts for EN 1092 type SZ1 flanges?

For the Flange connection kit, carbon steel, DIN 931 (EN 1092 type SZ1 flanges) with DIN 931 bolts (class 5.6), DIN 934 nuts (class 8) and DIN 125A washers (140 HV), recommended tightening torque depends on bolt size. Using standard torque values for class 5.6 bolts with lubricated electro-galvanized finish and washers, typical recommended torques are: - M8: 18â22 Nm - M10: 35â45 Nm - M12: 65â75 Nm - M16: 140â165 Nm - M20: 260â300 Nm Notes: 1) These values assume clean, lightly lubricated threads and washer contact; dry threads require ~25â30% higher torque. 2) Always verify bolt size from the kit/table in the product appendix and follow flange manufacturer or applicable standards (EN 1092 / bolting tables) for specific joint preload and gasket requirements. 3) Use calibrated torque tools and tighten in a star pattern to achieve even flange loading.

Can Flange connection kit, carbon steel, DIN 931 bolts (class 5.6) be used with gasket materials requiring higher preload for EN 1092 type SZ1?

No. Flange connection kit, carbon steel, DIN 931 (bolts class 5.6, nuts class 8, washers 140 HV) is not suitable where the EN 1092 type SZ1 gasket requires higher preload. Class 5.6 bolts have low proof strength and cannot reliably achieve the higher preload/pretension needed for tightness with high-demand gasket materials; using them risks gasket failure, flange leakage, bolt yielding or loss of preload. For SZ1 gaskets that specify higher preload, select bolts and nuts of appropriate mechanical class per the EN 1092 selection table (typically higher strength grades, e.g. 8.8 or 10.9 with matching nuts), and ensure correct lubrication and torque/bolt pretension procedures.

Can Flange connection kit, carbon steel, DIN 931 withstand vibration without additional locking methods for EN 1092 SZ1?

No. the Flange connection kit, carbon steel, DIN 931 as described is generally not suitable to reliably withstand significant vibration without additional locking methods for EN 1092 flanges of type SZ1. Why: - The kit includes DIN 931 bolts (class 5.6), DIN 934 nuts (class 8) and DIN 125A washers (140 HV) with electro-galvanized carbon steel. Bolt class 5.6 has relatively low tensile and yield strength compared with higher classes commonly recommended for flange connections under dynamic loads. - Vibration induces bolt pre-load relaxation, relative motion and risk of self-loosening of standard hex nuts. Plain washers do not prevent rotation or loss of clamping due to vibration. - EN 1092 flange joints under cyclic loads typically require proper bolt pre-load, correct material strength margin, and often positive locking (e.g., prevailing torque/nylon-insert or prevailing torque nuts, deformed thread locknuts, lock washers specifically rated for vibration, safety wire, castellated nuts with split pins, or thread-locking adhesives) or use of higher-grade bolts (e.g., 8.8/10.9) per designerâs specification. Recommendation: - For vibration-prone service, use higher-strength bolts (at least 8.8 or per the selection table/engineering spec), and apply positive locking methods appropriate to the environment (mechanical locking, prevailing torque nuts, or approved adhesives). Verify required pre-load/torque and re-tightening/inspection intervals per EN 1092 and project engineering standards.

Flange connection kit, carbon steel, DIN 931

All products, Flange couplings/

Additional information

Flange connection set (EN 1092), type SZ1. Included: DIN931 bolts – 4 pieces, DIN934 nuts – 4 pieces, and DIN125A washers – 4 pieces. Mechanical property class: 5.6 – bolts; 8 – nuts; 140HV – washers. Selection of bolts and nuts for flanges according to the table in the appendix. Material: carbon steel, electro-galvanized.

List of product variants

Article number	Product variant name	DN	BAR	Availability	Actions
TK-SZ1-M12-050-A-PG	Set (4 pcs.) M12x50 screws, nuts, washers, galvanized steel.	-	-	In stock	Enquiry
TK-SZ1-M12-055-A-PG	Set (4 pcs.) M12x55 screws, nuts, washers, galvanized steel.	-	-	In stock	Enquiry
TK-SZ1-M12-060-A-PG	Set (4 pcs.) M12x60 screws, nuts, washers, galvanized steel.	-	-	In stock	Enquiry
TK-SZ1-M12-070-A-PG	Set (4 pcs.) M12x70 screws, nuts, washers, galvanized steel.	-	-	In stock	Enquiry
TK-SZ1-M12-080-A-PG	Set (4 pcs.) M12x80 screws, nuts, washers, galvanized steel.	-	-	In stock	Enquiry
TK-SZ1-M16-060-A-PG	Set (4 pcs.) M16x60 screws, nuts, washers, galvanized steel.	-	-	In stock	Enquiry
TK-SZ1-M16-065-A-PG	Set (4 pcs.) M16x65 screws, nuts, washers, galvanized steel.	-	-	In stock	Enquiry
TK-SZ1-M16-070-A-PG	Set (4 pcs.) M16x70 screws, nuts, washers, galvanized steel.	-	-	In stock	Enquiry
TK-SZ1-M16-075-A-PG	Set (4 pcs.) M16x75 screws, nuts, washers, galvanized steel.	-	-	In stock	Enquiry
TK-SZ1-M16-080-A-PG	Set (4 pcs.) M16x80 screws, nuts, washers, galvanized steel.	-	-	In stock	Enquiry
TK-SZ1-M16-085-A-PG	Set (4 pcs.) M16x85 screws, nuts, washers, galvanized steel.	-	-	In stock	Enquiry
TK-SZ1-M16-090-A-PG	Set (4 pcs.) M16x90 screws, nuts, washers, galvanized steel.	-	-	In stock	Enquiry
TK-SZ1-M16-095-A-PG	Set (4 pcs.) M16x95 screws, nuts, washers, galvanized steel.	-	-	In stock	Enquiry
TK-SZ1-M16-100-A-PG	Set (4 pcs.) M16x100 screws, nuts, washers, galvanized steel.	-	-	In stock	Enquiry
TK-SZ1-M16-110-A-PG	Set (4 pcs.) M16x110 screws, nuts, washers, galvanized steel.	-	-	In stock	Enquiry
TK-SZ1-M16-120-A-PG	Set (4 pcs.) M16x120 screws, nuts, washers, galvanized steel.	-	-	In stock	Enquiry
TK-SZ1-M20-070-A-PG	Set (4 pcs.) M20x70 screws, nuts, washers, galvanized steel.	-	-	In stock	Enquiry
TK-SZ1-M20-075-A-PG	Set (4 pcs.) M20x75 screws, nuts, washers, galvanized steel.	-	-	In stock	Enquiry
TK-SZ1-M20-080-A-PG	Set (4 pcs.) M20x80 screws, nuts, washers, galvanized steel.	-	-	In stock	Enquiry
TK-SZ1-M20-100-A-PG	Set (4 pcs.) M20x100 screws, nuts, washers, galvanized steel.	-	-	In stock	Enquiry
TK-SZ1-M20-120-A-PG	Set (4 pcs.) M20x120 screws, nuts, washers, galvanized steel.	-	-	In stock	Enquiry
TK-SZ1-M24-090-A-PG	Set (4 pcs.) M24x90 screws, nuts, washers, galvanized steel.	-	-	In stock	Enquiry
TK-SZ1-M24-110-A-PG	Set (4 pcs.) M24x110 screws, nuts, washers, galvanized steel.	-	-	In stock	Enquiry
TK-SZ1-M24-120-A-PG	Set (4 pcs.) M24x120 screws, nuts, washers, galvanized steel.	-	-	In stock	Enquiry
TK-SZ1-M24-140-A-PG	Set (4 pcs.) M24x140 screws, nuts, washers, galvanized steel.	-	-	In stock	Enquiry

Do you need a larger quantity of products or a bespoke quote?

Call us: +48 61 653 02 22 or email us: tubes@tubes-international.com

SEND ENQUIRY

Flange connection set (EN 1092), type SZ1. Included: DIN931 bolts – 4 pieces, DIN934 nuts – 4 pieces, and DIN125A washers – 4 pieces. Mechanical property class: 5.6 – bolts; 8 – nuts; 140HV – washers. Selection of bolts and nuts for flanges according to the table in the appendix. Material: carbon steel, electro-galvanized.