GB/T 71-2018Slotted set screws with cone point (English PDF)

Foreword

This standard is one of the national standards for the "tightening screws" series. The series includes.

---GB/T 71 slotted tapered end set screws;

---GB/T 73 slotted flat end set screws;

---GB/T 74 slotted recessed set screws;

---GB/T 75 slotted long cylindrical end set screws;

---GB/T 77 hex flat end set screws;

---GB/T 78 hexagonal taper end set screws;

---GB/T 79 hexagonal cylindrical end set screws;

---GB/T 80 hex socket end set screws;

---GB/T 83 square head long cylindrical spherical end set screws;

---GB/T 84 square head concave end set screws;

---GB/T 85 square head long cylindrical end set screws;

---GB/T 86 square head short cylindrical cone end set screws;

---GB/T 821 square head flat end set screws.

This standard was drafted in accordance with the rules given in GB/T 1.1-2009.

This standard replaces GB/T 71-1985 "Slotted Cone End Set Screw". Compared with GB/T 71-1985, the main technical changes are as follows.

---The reference thread standard is unified to GB/T 193, GB/T 9145 (see Chapter 2, Table 2);

--- Increase the thread size of M3.5 (see Table 1);

--- Increase general technical conditions according to GB/T 16938 (see Table 2);

---The mechanical performance grade of stainless steel was modified to. A1-12H, A2-12H and A4-12H (see Table 2, Table 2 of 1985);

--- Add non-ferrous metals CU2, CU3 (see Table 2);

--- For steel screws, remove surface oxidation treatment, increase the technical requirements of untreated and non-electrolytic zinc sheet coating according to GB/T 5267.2 (see

Table 2, 1985 edition table 2);

--- For stainless steel screws, remove without treatment, increase the simple processing and passivation treatment technical requirements according to GB/T 5267.4 (see Table 2

1985 edition 2);

--- Increase the performance grade of steel and stainless steel screws "d < 1.6mm. according to the agreement" (see Table 2);

--- Add "If other technical requirements or surface treatment are required, the supply and demand agreement should be provided" (see Table 2);

--- Increase the surface defects of steel screws (see Table 2).

This standard uses the redrafting method to modify the use of ISO 7434.1983 "slotted tapered end set screws."

The technical differences between this standard and ISO 7434.1983 and their reasons are as follows.

--- Remove the ISO 7434.1983 provisions "If you need other technical requirements, ISO 3506 and ISO 4759-1 are selected." (see

ISO 7434. 1983 Chapter 1), not subject to the provisions of this standard;

--- In the normative reference documents, replace the international standards with Chinese standards (see Chapter 2), increase the reference to GB/T 90.2 (see Table 2),

GB/T 3098.16 (see Table 2), GB/T 5267.2 (see Table 2), GB/T 5267.4 (see Table 2), GB/T 5779.1 (see Table 2),

GB/T 16938 (see Table 2) and GB/T 1237 (see 5.1), delete the reference to ISO 888, ISO 4753, in order to comply with our country

Firmware base standard;

--- Increase the general technical conditions according to GB/T 16938 (see Table 2), in order to meet the development requirements of the set screws;

--- Add non-ferrous metals CU2, CU3 (see Table 2) to expand the scope of use of the product;

---The performance grade of stainless steel was modified to. A1-12H (see Table 2) to meet the new material of the set screw;

--- Increase the performance grade of steel and stainless steel screws "d < 1.6mm. according to the agreement" (see Table 2), to clarify the performance level of small specifications

Provision

--- For steel screws, remove surface oxidation treatment, increase the technical requirements of untreated and non-electrolytic zinc sheet coating according to GB/T 5267.2 (see

Table 2) to meet the corrosion requirements of steel screw surfaces;

--- For stainless steel screws, remove the untreated, add simple processing and passivation treatment technical requirements according to GB/T 5267.4 (see Table 2),

In order to meet the corrosion protection requirements of stainless steel screws;

--- In order to improve product quality, the surface defects of steel screws are increased according to the basic standards of fasteners;

--- Increase packaging technical requirements (see Table 2) to meet the basic standards of fasteners in China;

--- Modify the tag example as a simplified tag example (see 5.2) to comply with the provisions of GB/T 1237.

This standard was proposed by the China Machinery Industry Federation.

This standard is under the jurisdiction of the National Fastener Standardization Technical Committee (SAC/TC85).

This standard is drafted by. China Machine Productivity Promotion Center.

Participated in the drafting of this standard. Qifeng Precision Technology Co., Ltd., Dongfeng Commercial Vehicle Co., Ltd. Dongfeng Commercial Vehicle Technology Center, Zhejiang

Jiang Haili Co., Ltd., Yuhuan Tianhao Machinery Co., Ltd.

This standard is interpreted by the National Fastener Standardization Technical Committee.

The previous versions of the standards replaced by this standard are.

---GB 71-1958, GB 71-1966, GB 71-1976, GB/T 71-1985.

Slotted tapered end set screw

1 Scope

This standard specifies the type size, technical conditions and markings of the slotted taper set screws.

This standard is applicable to slotted taper end set screws with thread size M1.2~M12 and product grade A.

2 Normative references

The following documents are indispensable for the application of this document. For dated references, only dated versions apply to this article.

Pieces. For undated references, the latest edition (including all amendments) applies to this document.

GB/T 90.1 fastener acceptance inspection (GB/T 90.1-2002, ISO 3269.2000, IDT)

GB/T 90.2 Fastener Marking and Packaging

GB/T 193 Ordinary Thread Diameter and Pitch Series (GB/T 193-2003, ISO 261.1998, MOD)

GB/T 1237 fastener marking method (GB/T 1237-2000, eqvISO 8991.1986)

GB/T 3098.3 Fastener mechanical properties set screws (GB/T 3098.3-2016, ISO 898-5.2012, MOD)

GB/T 3098.16 Mechanical properties of fasteners, stainless steel set screws (GB/T 3098.16-2014, ISO 3506-3.2009, MOD)

GB/T 3103.1 fastener tolerance bolts, screws, studs and nuts (GB/T 3103.1-2002, idtISO 4759-1.2000)

GB/T 5267.1 Fastener Plating (GB/T 5267.1-2002, ISO 4042.1999, IDT)

GB/T 5267.2 fastener non-electrolytic zinc sheet coating (GB/T 5267.2-2017, ISO 10683.2014, IDT)

GB/T 5267.4 Fastener surface treatment Corrosion resistant stainless steel passivation treatment (GB/T 5267.4-2009, ISO 16048.2003, IDT)

GB/T 5276 fastener bolts, screws, studs and nuts size code and label (GB/T 5276-2015, ISO 225.

2010, MOD)

GB/T 5779.1 fasteners surface defects bolts, screws and studs general requirements (GB/T 5779.1-2000, idtISO

6157-1. 1988)

GB/T 9145 medium thread precision, preferred series of extreme dimensions (GB/T 9145-2003, ISO 965-2.1998, MOD)

General technical requirements for GB/T 16938 fastener bolts, screws, studs and nuts (GB/T 16938-2008, ISO 8992.

2005, IDT)

3 type size

The type and dimensions of the screws are shown in Figure 1 and Table 1.

The size code and label should conform to GB/T 5276.

a Short screws with a nominal length above the imaginary step line in Table 1 shall be made 120°.

b Long screws with a nominal length below the imaginary step line in Table 1 shall be made 90°, and short screws above the imaginary step line shall be made 120°. 90° or 120° is only available for

The end portion within the threaded diameter.

c The length of the incomplete thread u <= 2P.