V.1 Standard Ulir. Standard ulir atau drad atau sney pipa yang digunakan untuk pekerjaan instalasi pipa adalah berbentuk V dengan sudut 60º. Memiliki perbedaan tinggi yang kecil antara awal ulir dan akhir ulir, yaitu 1/32” per inci inci panjang ulir. Perbedaan tinggi tersebut memberikan sambungan kedap air. Hal yang perlu diperhatikan adalah jumlah ulir pipa, ulir sejumlah 7 (tujuh) pertama dari ujung pipa merupakan ulir sempurna, yaitu memiliki sudut tajam pada bagian atas dan bagian bawah. Ulir selanjutnya sejumlah 2 (dua) atau 3 (tiga) memiliki sudut tajam pada bagian bawah dan sisanya memiliki sudut tumpul pada bagian atas dan bagian bawah ulir terakhir ini merupakan akhir ulir serta tidak memiliki nilai kedap. Jika ulir-ulir sempurna sempurna tersebut tumpul atau rusak, kebocoran akan terjadi.
1” 1/32 “
60°
UL I R P I P A S T A ND ND A R D A M E R I K A ( A M E R I C A N S T A N D A R D P I P E T HR HR E A D S )
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Ulir Efektif
Jumlah ulir per inci untuk setiap ukuran diameter pipa, sebagai berikut : JUMLAH ULIR PER DIAMETER PIPA (INCI)
MODUL
INCI
1/8
27
¼ , 3/8
18
½ , 3/4
14
1 hingga 2
11 ½
2 ½ hingga 12
8
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V.2 Ulir Pipa Standard Inggris (British Standard Pipe Threads)
BSP – Ukuran Dasar
MODUL
NOM. DIA. Inch
THREADS PER Inch
EFFECT. DIA. Inch
MINOR DIA. Inch
28 19 19 14
MAJOR DIA. Inch .3830 .5180 .6560 .8250
1/8 1/4 3/8 1/2
.3601 .4843 .6223 .7793
.3372 .4506 .5886 .7336
5/8 3/4 7/8
14 14 14
.9020 1.0410 1.1819
.8563 .9953 1.1433
.8106 .9496 1.0976
1
11
1.3090
1.2508
1.1926
1 1/4
11
1.6500
1.5918
1.5336
1 1/2
11
1.8820
1.8238
1.7656
2
11
2.3470
2.2888
2.2306
2 1/2 3
11 11
2.9600 3.4600
2.9018 3.4018
2.8436 3.3436
4
11
4.4500
4.3918
4.3336
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MODUL
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BSPT – Ukuran Dasar THREADS PER Inch
MAJOR DIA. Inch
GAGE LENGTH Inch
1/8
28
.3830
.1563
1/4
19
.5180
.2367
3/8
19
.6560
.2500
1/2
14
.8250
.3214
3/4
14
1.0410
1
11
1.3090
.4091
1 1/4
11
1.6500
.5000
1 1/2
11
1.8820
.5000
2
11
2.3470
.6250
2 1/2
11
2.9600
.6875
3
11
3.4600
.8125
NOM. DIA. (Inch)
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.3750
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DAFTAR MACAM-MACAM STANDARD ULIR DAN SINGKATANNYA
ACME-C Acme Thread-Centralizing ACME-G Acme Thread-General Purpose AMO American Standard Microscope Objective Thread ANPT Aeronautical National Form Taper Pipe Thread (Ground thread tap marked NPT) BA British Association Standard Thread BSF British Standard Fine Thread Series BSP British Standard Pipe BSPP British Standard Pipe (Parallel) Thread BSPT British Standard Taper Pipe Thread BSW British Standard Whitworth Coarse Thread Series M Metric ScrewThread Series N American National 8, 12 and 16 Thread Series (8N, 12N, 16N) N BUTT American Buttress Screw Thread NC American National Coarse Thread Series NEF American National Extra Fine Thread Series NF American National Fine Thread Series NGO National Gas Outlet Thread NGT National Gas Taper Thread (see "SGT") NH American National Hose Coupling and Fire Hose Coupling Threads NPS For tap marking only (See NPSC, NPSM) NPSC American National Standard Straight Pipe Thread in Pipe Couplings (Tap marked NPS) NPSF Dryseal American National Standard Fuel Internal Straight Pipe Thread NPSH American National Standard Straight Pipe Thread for Hose Couplings NPSI Dryseal American National Standard Intermediate Internal Straight Pipe Thread NPSL American National Standard Straight Pipe Thread for Loose Fitting Mechanical Joints with Locknuts NPSM
American National Standard Straight Pipe Threads for Free-Fitting Mechanical Joints for Fixtures (Tap marked NPS)
NPT NPTF NPTR
American National Standard Taper Pipe Thread (lihat ANPT, NPTR) Dryseal American National Standard Taper Pipe Thread American National Standard Taper Pipe Thread for Railing Joints (Tap marked NPT)
NS PG PTF
American National Thread-Special Panzer Gewinde Dryseal SAE Short Taper Pipe Thread
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SGT SPL-PTF STI Stub Acme *UN *UNC *UNEF *UNF UNJ**
Special Gas Taper Thread Dryseal Special Taper Pipe Thread Special Thread for Helical Coil Wire Screw Thread Inserts Stub Acme Thread Unified Constant Pitch Thread Series Unified Coarse Thread Series Unified Extra Fine Thread Series Unified Fine Thread Series Unified Thread Series with a 0.15011P to 0.18042P Controlled Root Radius on External Thread only.
UNJC
Unified Coarse Thread Series with a 0.15011P to 0.18042P Controlled Root Radius on External Thread only.
UNJF
Unified Fine Thread Series with a 0.15011P to 0.18042P Controlled Root Radius on External Thread only.
UNM UNR
Unified Miniature Thread Series Unified Constant Pitch Thread Series with a 0.108P to 0.144P Controlled Root Radius; Ext. thread only.
UNRC
Unified Coarse Thread Series with a 0.108P to 0.144P Controlled Root Radius; Ext. thread only.
UNRF
Unified Fine Thread Series with a 0.108P to 0.144P Controlled Root Radius; External thread only.
*UNS V
Unified Thread-Special A 60° "V" thread with Truncated Crest and Root. The theoretical "V" Form is usually flatted to the user’s specifications. British Standard Whitworth Special Thread
WHIT
Soal : 1. Jelaskan ulir pipa galvanis sesuai kaidah standardnya ? 2. Bilamana ulir rusak, bagaimana cara mengatasinya ? 3. Apa yang dimaksud dengan ulir sempurna sesuai standard ulir pipa galvanis ? 4. Sebutkan dengan tepat, mengapa pipa yang akan disambung dengan alat sambung (fitting) dipasang/dililit dengan TBA ?
