Screws and Nuts Technical Summary

1. BJ748 Clamp Screws

Material and Finish: Steel (SCM435), black oxide finish, quenched and tempered (Rc 33-39).

Specifications: Various sizes with metric threads from M6 to M24, detailed dimensions including length (L, L1, L2, L3), diameter (D), radius (R), and weight provided.

Performance: Allowable screw torque and clamping force values are specified for each part number, ensuring proper application and safety.

2. Knurled Head Screws BJ764

Material: Steel (S45C) and stainless steel (SUS440C), black oxide finish, quenched and tempered.

Features: Induction hardened edges for durability. Available in steel and stainless steel variants with detailed dimensions and weights.

3. Ball Thumbs Screws BCR and BCF

Material and Treatment: Steel (SCM435, SUJ2), stainless steel (SUS440C, SUS304), black oxide finish, quenched and tempered with hardness ranging Rc33-67 depending on type.

Design: Available in flat-contact and round-contact ball styles. Flat-contact style supports soft workpieces without damage, round-contact supports angled workpieces.

Dimensions: Detailed sizes including ball diameter, thread size, length, and weight are provided for each model.

4. Ball Screws BSR and BSF (Steel & Stainless Steel Balls)

Material and Treatment: Steel (SCM435, SUJ2), stainless steel (SUS440C, SUS304), black oxide finish, quenched and tempered with hardness Rc33-67.

Design: Flat-contact and round-contact ball types available, suitable for clamping and positioning applications with ball detent elements.

Dimensions and Weights: Comprehensive data on thread sizes, lengths, diameters, and weights for each part number.

5. Nose Screws USC

Material: Steel (SCM435) body with polyurethane plastic nose (Shore A90) to prevent marring of workpiece surfaces.

Finish: Black oxide finish, heat treated to Rc33-39.

Dimensions: Various thread sizes and lengths with corresponding weights.

6. BJ730 Swivel Contact Bolts

Material: Steel (S45C, SCM435), SUJ2 steel for ball, black oxide finish, quenched and tempered with hardness Rc33-67.

Design: Available in flat and serrated contact faces, with load capacities ranging from 2 kN to 200 kN depending on size.

Dimensions: Detailed metric thread sizes, lengths, heights, diameters, and weights provided.

Note: These bolts do not include ball detent elements; for those, refer to BUH Hex-Head Swivel Gripper Screws.

7. Toggle Pads BJ731

Material: Steel (S45C) with case hardened contact face and black oxide finish; also available in stainless steel (SUS304).

Features: Knurled knob for adjustment, adjustable stop, and high load capacities (up to 37,500 N static load).

Dimensions: Various sizes with detailed measurements and weights.

8. BJ750-N Clamping Screws

Material and Finish: Steel (S45C) with black oxide or chrome plated finish; also available in stainless steel (SUS303).

Application: Designed to clamp workpieces from above or below.

Dimensions: Multiple thread sizes and lengths with corresponding weights.

9. Knurled Nuts BJ753 and BJ754

Material: BJ753 made from S45C steel with black oxide finish; BJ754 made from SUM24L steel with black oxide finish.

Dimensions: Various metric thread sizes with detailed diameter, height, and weight data.

General Notes and Recommendations

• Materials are selected for strength and corrosion resistance, with heat treatments specified to achieve desired hardness levels.
• Black oxide finish is common for corrosion resistance and appearance; some parts are chrome plated or stainless steel for enhanced corrosion resistance.
• Ball detent elements are included in some screw types for positioning and clamping precision; others require separate products.
• Flat-contact ball styles are recommended for soft workpieces to avoid damage, while round-contact styles support angled or hard workpieces.
• Torque and clamping force specifications must be adhered to for safe and effective use.
• Polyurethane noses on nose screws prevent marring of delicate surfaces.

Summary of Critical Parameters

Product Type	Material	Finish	Hardness (Rc)	Thread Sizes	Load Capacity / Clamping Force
BJ748 Clamp Screws	SCM435 Steel	Black oxide	33-39	M6 to M24	Specified per part (up to ~100 kN)
BJ764 Knurled Head Screws	Steel, Stainless Steel	Black oxide	Induction hardened edges	M5 to M16	Not specified
BCR/BCF Ball Thumb Screws	Steel, Stainless Steel	Black oxide	33-67	M6 to M16	Varies by model
BSR/BSF Ball Screws	Steel, Stainless Steel	Black oxide	33-67	M4 to M16	Varies by model
USC Nose Screws	Steel with Polyurethane nose	Black oxide	33-39	M5 to M16	Not specified
BJ730 Swivel Contact Bolts	Steel (S45C, SCM435), SUJ2	Black oxide	33-67	M4 to M20	2 kN to 200 kN
BJ731 Toggle Pads	Steel, Stainless Steel	Black oxide	Case hardened	M8 to M20	Up to 37,500 N static load
BJ750-N Clamping Screws	Steel, Stainless Steel	Black oxide, Chrome plated	Not specified	M5 to M12	Not specified
BJ753/BJ754 Knurled Nuts	S45C Steel, SUM24L Steel	Black oxide	Not specified	M6 to M16	Not specified

This document provides comprehensive technical data for various types of screws and nuts used in clamping and fastening applications, emphasizing material properties, finishes, dimensions, and performance parameters to guide proper selection and use.