Butt-welding fittings are subjected to strict in-process inspection at each stage of the production process –from starting materials handling to finished product shipping. We are visually examined for conformity to company specifications and tested under the applicable ASTM, ASME, MSS and JIS codes and standards. We are also tested to make sure we conform to our intended use. Upon request, we call in officially certified test agents to witness the inspection procedures. Butt-welding fitting are manufactured in conformity with the following standard.

Applicable standards

ASTM A234 Pipe Fittings of Wrought Carbon Steel and Alloy Steel for Moderate and High Temperatures Service
ASTM A403 Wrought Austenitic Stainless Steel Piping Fittings
ASTM A420 Piping Fittings of Wrought Carbon Steel and Alloy Steel for Low- Temperatures Service
ASTM A860 Wrought High-Strength Low-Alloy Steel Butt-welding Fittings
ASME B16.9 Factory- Made Wrought Steel Butt-welding Fittings
MSS SP-43  Wrought Stainless Steel Butt-welding Fittings
MSS SP-75  High- Test Wrought Steel Butt-welding Fittings
JIS B2311   Steel Butt-Welding Pipe Fittings for Ordinary Use
JIS B2312   Steel Butt-Welding Pipe Fittings
JIS B2313   Steel Plate Butt-Welding Pipe Fittings



Butt-welding fittings are made of materials which meet ASTM and intracompany specifications.

Starting material inspection is carried out at follows:

1) Dimensional Inspection

     Dimensions are inspected at each end of the purchased material.

2) Visual Inspection

     Inspected is performed according to THAI BENKAN CO., LTD. “acceptable surface condition” standard.

3) Collating

     Judgement is made as to whether is worthy of the inspection by computorised collating the described items with the materials certificates.

The following other inspections are performed if necessary.

- Ultrasonic Examination
- Magnetic Particle Examination
- Liquid Penetrant Examination
- Ultrasonic Thickness Inspection
- Mechanical Test
- Others


Butt-welding fittings are manufactured with carefully selected materials of the finest metallurgical quality on well-controlled jigs, tools or molds based on THAI BENKAN CO.,LTD Various working standards. Meeting quality specifications is a key feature of BKL butt-welding fittings.

The following are the major in-process inspection items.

- Visual Inspection
- Dimensional Inspection
- Shape Inspection
- Hardness Test
- Temperature Check
- Processing Conditions Check
- Material Identification ( by marking )
- Others


The final inspection of BKL butt-welding fitting is performed as follows:

1) Standard Product Inspection
     Applicable for BKL butt-welding fittings produced under ASME B16.9 and other specifications


Butt-welding fittings are visually inspected to confirm that both internal and external surfaces are smooth and without harmful defects. THAI BENKAN CO.,LTD. “acceptable surface condition” standard is used as the standard for visual tests.


Butt-welding fittings are inspected for conformity with ASME or MSS and JIS dimensional tolerances

2) Special Product Inspection
    Applicable for every products manufactured to meet specifications requested by customers.


Butt-welding fittings are visually inspected. Criteria are based on those of the standard product.

Special specifications are determined by agreement between the customer and THAI BENKAN CO.,LTD.


The inspection is usually based on specifications stipulated by the customer.


In the case of special requirements specified by the customer, nondestructive examinations and mechanical tests are performed.


Copyright © 2004 ThaiBenkan Co., Ltd. All rights reserved.  
58 Soi Watkrunai, Bangkru Suksawat 70, Prapadaeng, Samutprakarn 10130, Thailand.
Tel : 66 02 463-6235-7 Fax : 66 02 463-8241